Merge pull request #4001 from Ultimaker/mypy_fixes

Fix typing

cura/API/Backups.py

@@ -1,5 +1,7 @@
 # Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
+from typing import Tuple, Optional
+
 from cura.Backups.BackupsManager import BackupsManager
 
 
@@ -17,7 +19,7 @@ class Backups:
     ##  Create a new back-up using the BackupsManager.
     #   \return Tuple containing a ZIP file with the back-up data and a dict
     #   with metadata about the back-up.
-    def createBackup(self) -> (bytes, dict):
+    def createBackup(self) -> Tuple[Optional[bytes], Optional[dict]]:
         return self.manager.createBackup()
 
     ##  Restore a back-up using the BackupsManager.

cura/Arranging/ArrangeObjectsAllBuildPlatesJob.py

@@ -20,14 +20,14 @@ from typing import List
 
 ##  Do arrangements on multiple build plates (aka builtiplexer)
 class ArrangeArray:
-    def __init__(self, x: int, y: int, fixed_nodes: List[SceneNode]):
+    def __init__(self, x: int, y: int, fixed_nodes: List[SceneNode]) -> None:
         self._x = x
         self._y = y
         self._fixed_nodes = fixed_nodes
         self._count = 0
         self._first_empty = None
         self._has_empty = False
-        self._arrange = []
+        self._arrange = []  # type: List[Arrange]
 
     def _update_first_empty(self):
         for i, a in enumerate(self._arrange):
@@ -48,16 +48,17 @@ class ArrangeArray:
         return self._count
 
     def get(self, index):
+        print(self._arrange)
         return self._arrange[index]
 
     def getFirstEmpty(self):
-        if not self._is_empty:
+        if not self._has_empty:
             self.add()
         return self._arrange[self._first_empty]
 
 
 class ArrangeObjectsAllBuildPlatesJob(Job):
-    def __init__(self, nodes: List[SceneNode], min_offset = 8):
+    def __init__(self, nodes: List[SceneNode], min_offset = 8) -> None:
         super().__init__()
         self._nodes = nodes
         self._min_offset = min_offset

cura/Arranging/ArrangeObjectsJob.py

@@ -20,7 +20,7 @@ from typing import List
 
 
 class ArrangeObjectsJob(Job):
-    def __init__(self, nodes: List[SceneNode], fixed_nodes: List[SceneNode], min_offset = 8):
+    def __init__(self, nodes: List[SceneNode], fixed_nodes: List[SceneNode], min_offset = 8) -> None:
         super().__init__()
         self._nodes = nodes
         self._fixed_nodes = fixed_nodes

cura/Backups/Backup.py

@@ -28,12 +28,12 @@ class Backup:
     # Re-use translation catalog.
     catalog = i18nCatalog("cura")
 
-    def __init__(self, zip_file: bytes = None, meta_data: dict = None):
+    def __init__(self, zip_file: bytes = None, meta_data: dict = None) -> None:
         self.zip_file = zip_file  # type: Optional[bytes]
         self.meta_data = meta_data  # type: Optional[dict]
 
     ##  Create a back-up from the current user config folder.
-    def makeFromCurrent(self) -> (bool, Optional[str]):
+    def makeFromCurrent(self) -> None:
         cura_release = CuraApplication.getInstance().getVersion()
         version_data_dir = Resources.getDataStoragePath()
 
@@ -54,6 +54,8 @@ class Backup:
         # Create an empty buffer and write the archive to it.
         buffer = io.BytesIO()
         archive = self._makeArchive(buffer, version_data_dir)
+        if archive is None:
+            return
         files = archive.namelist()
         
         # Count the metadata items. We do this in a rather naive way at the moment.

cura/Backups/BackupsManager.py

@@ -1,6 +1,6 @@
 # Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
-from typing import Optional
+from typing import Optional, Tuple
 
 from UM.Logger import Logger
 from cura.Backups.Backup import Backup
@@ -18,7 +18,7 @@ class BackupsManager:
     ##  Get a back-up of the current configuration.
     #   \return A tuple containing a ZipFile (the actual back-up) and a dict
     #   containing some metadata (like version).
-    def createBackup(self) -> (Optional[bytes], Optional[dict]):
+    def createBackup(self) -> Tuple[Optional[bytes], Optional[dict]]:
         self._disableAutoSave()
         backup = Backup()
         backup.makeFromCurrent()

cura/CuraActions.py

@@ -1,12 +1,12 @@
-# Copyright (c) 2017 Ultimaker B.V.
+# Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
 
 from PyQt5.QtCore import QObject, QUrl
 from PyQt5.QtGui import QDesktopServices
-from UM.FlameProfiler import pyqtSlot
+from typing import List, TYPE_CHECKING
 
 from UM.Event import CallFunctionEvent
-from UM.Application import Application
+from UM.FlameProfiler import pyqtSlot
 from UM.Math.Vector import Vector
 from UM.Scene.Selection import Selection
 from UM.Scene.Iterator.BreadthFirstIterator import BreadthFirstIterator
@@ -14,6 +14,7 @@ from UM.Operations.GroupedOperation import GroupedOperation
 from UM.Operations.RemoveSceneNodeOperation import RemoveSceneNodeOperation
 from UM.Operations.TranslateOperation import TranslateOperation
 
+import cura.CuraApplication
 from cura.Operations.SetParentOperation import SetParentOperation
 from cura.MultiplyObjectsJob import MultiplyObjectsJob
 from cura.Settings.SetObjectExtruderOperation import SetObjectExtruderOperation
@@ -23,28 +24,30 @@ from cura.Operations.SetBuildPlateNumberOperation import SetBuildPlateNumberOper
 
 from UM.Logger import Logger
 
+if TYPE_CHECKING:
+    from UM.Scene.SceneNode import SceneNode
 
 class CuraActions(QObject):
-    def __init__(self, parent = None):
+    def __init__(self, parent: QObject = None) -> None:
         super().__init__(parent)
 
     @pyqtSlot()
-    def openDocumentation(self):
+    def openDocumentation(self) -> None:
         # Starting a web browser from a signal handler connected to a menu will crash on windows.
         # So instead, defer the call to the next run of the event loop, since that does work.
         # Note that weirdly enough, only signal handlers that open a web browser fail like that.
         event = CallFunctionEvent(self._openUrl, [QUrl("http://ultimaker.com/en/support/software")], {})
-        Application.getInstance().functionEvent(event)
+        cura.CuraApplication.CuraApplication.getInstance().functionEvent(event)
 
     @pyqtSlot()
-    def openBugReportPage(self):
+    def openBugReportPage(self) -> None:
         event = CallFunctionEvent(self._openUrl, [QUrl("http://github.com/Ultimaker/Cura/issues")], {})
-        Application.getInstance().functionEvent(event)
+        cura.CuraApplication.CuraApplication.getInstance().functionEvent(event)
 
     ##  Reset camera position and direction to default
     @pyqtSlot()
     def homeCamera(self) -> None:
-        scene = Application.getInstance().getController().getScene()
+        scene = cura.CuraApplication.CuraApplication.getInstance().getController().getScene()
         camera = scene.getActiveCamera()
         camera.setPosition(Vector(-80, 250, 700))
         camera.setPerspective(True)
@@ -72,17 +75,17 @@ class CuraActions(QObject):
     #   \param count The number of times to multiply the selection.
     @pyqtSlot(int)
     def multiplySelection(self, count: int) -> None:
-        min_offset = Application.getInstance().getBuildVolume().getEdgeDisallowedSize() + 2  # Allow for some rounding errors
+        min_offset = cura.CuraApplication.CuraApplication.getInstance().getBuildVolume().getEdgeDisallowedSize() + 2  # Allow for some rounding errors
         job = MultiplyObjectsJob(Selection.getAllSelectedObjects(), count, min_offset = max(min_offset, 8))
         job.start()
 
     ##  Delete all selected objects.
     @pyqtSlot()
     def deleteSelection(self) -> None:
-        if not Application.getInstance().getController().getToolsEnabled():
+        if not cura.CuraApplication.CuraApplication.getInstance().getController().getToolsEnabled():
             return
 
-        removed_group_nodes = []
+        removed_group_nodes = [] #type: List[SceneNode]
         op = GroupedOperation()
         nodes = Selection.getAllSelectedObjects()
         for node in nodes:
@@ -96,7 +99,7 @@ class CuraActions(QObject):
                     op.addOperation(RemoveSceneNodeOperation(group_node))
 
             # Reset the print information
-            Application.getInstance().getController().getScene().sceneChanged.emit(node)
+            cura.CuraApplication.CuraApplication.getInstance().getController().getScene().sceneChanged.emit(node)
 
         op.push()
 
@@ -111,7 +114,7 @@ class CuraActions(QObject):
         for node in Selection.getAllSelectedObjects():
             # If the node is a group, apply the active extruder to all children of the group.
             if node.callDecoration("isGroup"):
-                for grouped_node in BreadthFirstIterator(node):
+                for grouped_node in BreadthFirstIterator(node): #type: ignore #Ignore type error because iter() should get called automatically by Python syntax.
                     if grouped_node.callDecoration("getActiveExtruder") == extruder_id:
                         continue
 
@@ -143,7 +146,7 @@ class CuraActions(QObject):
         Logger.log("d", "Setting build plate number... %d" % build_plate_nr)
         operation = GroupedOperation()
 
-        root = Application.getInstance().getController().getScene().getRoot()
+        root = cura.CuraApplication.CuraApplication.getInstance().getController().getScene().getRoot()
 
         nodes_to_change = []
         for node in Selection.getAllSelectedObjects():
@@ -151,7 +154,7 @@ class CuraActions(QObject):
             while parent_node.getParent() != root:
                 parent_node = parent_node.getParent()
 
-            for single_node in BreadthFirstIterator(parent_node):
+            for single_node in BreadthFirstIterator(parent_node): #type: ignore #Ignore type error because iter() should get called automatically by Python syntax.
                 nodes_to_change.append(single_node)
 
         if not nodes_to_change:
@@ -164,5 +167,5 @@ class CuraActions(QObject):
 
         Selection.clear()
 
-    def _openUrl(self, url):
+    def _openUrl(self, url: QUrl) -> None:
         QDesktopServices.openUrl(url)

cura/CuraApplication.py

@@ -2,7 +2,6 @@
 # Cura is released under the terms of the LGPLv3 or higher.
 
 import copy
-import json
 import os
 import sys
 import time
@@ -14,7 +13,8 @@ from PyQt5.QtGui import QColor, QIcon
 from PyQt5.QtWidgets import QMessageBox
 from PyQt5.QtQml import qmlRegisterUncreatableType, qmlRegisterSingletonType, qmlRegisterType
 
-from UM.Qt.QtApplication import QtApplication
+from typing import cast, TYPE_CHECKING
+
 from UM.Scene.SceneNode import SceneNode
 from UM.Scene.Camera import Camera
 from UM.Math.Vector import Vector
@@ -28,6 +28,8 @@ from UM.Scene.Iterator.DepthFirstIterator import DepthFirstIterator
 from UM.Mesh.ReadMeshJob import ReadMeshJob
 from UM.Logger import Logger
 from UM.Preferences import Preferences
+from UM.Qt.QtApplication import QtApplication #The class we're inheriting from.
+from UM.View.SelectionPass import SelectionPass #For typing.
 from UM.Scene.Selection import Selection
 from UM.Scene.GroupDecorator import GroupDecorator
 from UM.Settings.ContainerStack import ContainerStack
@@ -109,14 +111,12 @@ from UM.FlameProfiler import pyqtSlot
 
 numpy.seterr(all = "ignore")
 
-MYPY = False
+try:
-if not MYPY:
+    from cura.CuraVersion import CuraVersion, CuraBuildType, CuraDebugMode
-    try:
+except ImportError:
-        from cura.CuraVersion import CuraVersion, CuraBuildType, CuraDebugMode
+    CuraVersion = "master"  # [CodeStyle: Reflecting imported value]
-    except ImportError:
+    CuraBuildType = ""
-        CuraVersion = "master"  # [CodeStyle: Reflecting imported value]
+    CuraDebugMode = False
-        CuraBuildType = ""
-        CuraDebugMode = False
 
 
 class CuraApplication(QtApplication):
@@ -1720,7 +1720,7 @@ class CuraApplication(QtApplication):
     def _onContextMenuRequested(self, x: float, y: float) -> None:
         # Ensure we select the object if we request a context menu over an object without having a selection.
         if not Selection.hasSelection():
-            node = self.getController().getScene().findObject(self.getRenderer().getRenderPass("selection").getIdAtPosition(x, y))
+            node = self.getController().getScene().findObject(cast(SelectionPass, self.getRenderer().getRenderPass("selection")).getIdAtPosition(x, y))
             if node:
                 while(node.getParent() and node.getParent().callDecoration("isGroup")):
                     node = node.getParent()

cura/Machines/ContainerNode.py

@@ -1,7 +1,7 @@
 # Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
 
-from typing import Optional
+from typing import Optional, Any, Dict, Union, TYPE_CHECKING
 
 from collections import OrderedDict
 
@@ -9,6 +9,9 @@ from UM.ConfigurationErrorMessage import ConfigurationErrorMessage
 from UM.Logger import Logger
 from UM.Settings.InstanceContainer import InstanceContainer
 
+if TYPE_CHECKING:
+    from cura.Machines.QualityGroup import QualityGroup
+
 
 ##
 # A metadata / container combination. Use getContainer() to get the container corresponding to the metadata.
@@ -23,10 +26,16 @@ from UM.Settings.InstanceContainer import InstanceContainer
 class ContainerNode:
     __slots__ = ("metadata", "container", "children_map")
 
-    def __init__(self, metadata: Optional[dict] = None):
+    def __init__(self, metadata: Optional[Dict[str, Any]] = None) -> None:
         self.metadata = metadata
         self.container = None
-        self.children_map = OrderedDict()
+        self.children_map = OrderedDict() #type: OrderedDict[str, Union[QualityGroup, ContainerNode]]
+
+    ##  Get an entry value from the metadata
+    def getMetaDataEntry(self, entry: str, default: Any = None) -> Any:
+        if self.metadata is None:
+            return default
+        return self.metadata.get(entry, default)
 
     def getChildNode(self, child_key: str) -> Optional["ContainerNode"]:
         return self.children_map.get(child_key)
@@ -50,4 +59,4 @@ class ContainerNode:
         return self.container
 
     def __str__(self) -> str:
-        return "%s[%s]" % (self.__class__.__name__, self.metadata.get("id"))
+        return "%s[%s]" % (self.__class__.__name__, self.getMetaDataEntry("id"))

cura/Machines/MaterialGroup.py

@@ -18,10 +18,10 @@ from cura.Machines.MaterialNode import MaterialNode #For type checking.
 class MaterialGroup:
     __slots__ = ("name", "is_read_only", "root_material_node", "derived_material_node_list")
 
-    def __init__(self, name: str, root_material_node: MaterialNode):
+    def __init__(self, name: str, root_material_node: MaterialNode) -> None:
         self.name = name
         self.is_read_only = False
-        self.root_material_node = root_material_node
+        self.root_material_node = root_material_node # type: MaterialNode
         self.derived_material_node_list = [] #type: List[MaterialNode]
 
     def __str__(self) -> str:

cura/Machines/MaterialManager.py

@@ -4,6 +4,7 @@
 from collections import defaultdict, OrderedDict
 import copy
 import uuid
+from typing import Dict
 from typing import Optional, TYPE_CHECKING
 
 from PyQt5.Qt import QTimer, QObject, pyqtSignal, pyqtSlot
@@ -263,7 +264,7 @@ class MaterialManager(QObject):
     # Return a dict with all root material IDs (k) and ContainerNodes (v) that's suitable for the given setup.
     #
     def getAvailableMaterials(self, machine_definition: "DefinitionContainer", extruder_variant_name: Optional[str],
-                              diameter: float) -> dict:
+                              diameter: float) -> Dict[str, MaterialNode]:
         # round the diameter to get the approximate diameter
         rounded_diameter = str(round(diameter))
         if rounded_diameter not in self._diameter_machine_variant_material_map:
@@ -288,7 +289,7 @@ class MaterialManager(QObject):
         #  3. generic material (for fdmprinter)
         machine_exclude_materials = machine_definition.getMetaDataEntry("exclude_materials", [])
 
-        material_id_metadata_dict = dict()
+        material_id_metadata_dict = dict() # type: Dict[str, MaterialNode]
         for node in nodes_to_check:
             if node is not None:
                 # Only exclude the materials that are explicitly specified in the "exclude_materials" field.
@@ -434,7 +435,7 @@ class MaterialManager(QObject):
 
         nodes_to_remove = [material_group.root_material_node] + material_group.derived_material_node_list
         for node in nodes_to_remove:
-            self._container_registry.removeContainer(node.metadata["id"])
+            self._container_registry.removeContainer(node.getMetaDataEntry("id", ""))
 
     #
     # Methods for GUI
@@ -445,22 +446,27 @@ class MaterialManager(QObject):
     #
     @pyqtSlot("QVariant", str)
     def setMaterialName(self, material_node: "MaterialNode", name: str):
-        root_material_id = material_node.metadata["base_file"]
+        root_material_id = material_node.getMetaDataEntry("base_file")
+        if root_material_id is None:
+            return
         if self._container_registry.isReadOnly(root_material_id):
             Logger.log("w", "Cannot set name of read-only container %s.", root_material_id)
             return
 
         material_group = self.getMaterialGroup(root_material_id)
         if material_group:
-            material_group.root_material_node.getContainer().setName(name)
+            container = material_group.root_material_node.getContainer()
+            if container:
+                container.setName(name)
 
     #
     # Removes the given material.
     #
     @pyqtSlot("QVariant")
     def removeMaterial(self, material_node: "MaterialNode"):
-        root_material_id = material_node.metadata["base_file"]
+        root_material_id = material_node.getMetaDataEntry("base_file")
-        self.removeMaterialByRootId(root_material_id)
+        if root_material_id is not None:
+            self.removeMaterialByRootId(root_material_id)
 
     #
     # Creates a duplicate of a material, which has the same GUID and base_file metadata.
@@ -539,6 +545,10 @@ class MaterialManager(QObject):
         root_material_id = self.getRootMaterialIDForDiameter(root_material_id, approximate_diameter)
         material_group = self.getMaterialGroup(root_material_id)
 
+        if not material_group:  # This should never happen
+            Logger.log("w", "Cannot get the material group of %s.", root_material_id)
+            return ""
+
         # Create a new ID & container to hold the data.
         new_id = self._container_registry.uniqueName("custom_material")
         new_metadata = {"name": catalog.i18nc("@label", "Custom Material"),

cura/Machines/MaterialNode.py

@@ -1,7 +1,6 @@
 # Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
-
+from typing import Optional, Dict
-from typing import Optional
 
 from .ContainerNode import ContainerNode
 
@@ -15,7 +14,6 @@ from .ContainerNode import ContainerNode
 class MaterialNode(ContainerNode):
     __slots__ = ("material_map", "children_map")
 
-    def __init__(self, metadata: Optional[dict] = None):
+    def __init__(self, metadata: Optional[dict] = None) -> None:
         super().__init__(metadata = metadata)
-        self.material_map = {}  # material_root_id -> material_node
+        self.material_map = {}  # type: Dict[str, MaterialNode] # material_root_id -> material_node
-        self.children_map = {}  # mapping for the child nodes

cura/Machines/Models/QualityProfilesDropDownMenuModel.py

@@ -83,7 +83,7 @@ class QualityProfilesDropDownMenuModel(ListModel):
 
         self.setItems(item_list)
 
-    def _fetchLayerHeight(self, quality_group: "QualityGroup"):
+    def _fetchLayerHeight(self, quality_group: "QualityGroup") -> float:
         global_stack = self._machine_manager.activeMachine
         if not self._layer_height_unit:
             unit = global_stack.definition.getProperty("layer_height", "unit")
@@ -94,10 +94,12 @@ class QualityProfilesDropDownMenuModel(ListModel):
         default_layer_height = global_stack.definition.getProperty("layer_height", "value")
 
         # Get layer_height from the quality profile for the GlobalStack
+        if quality_group.node_for_global is None:
+            return float(default_layer_height)
         container = quality_group.node_for_global.getContainer()
 
         layer_height = default_layer_height
-        if container.hasProperty("layer_height", "value"):
+        if container and container.hasProperty("layer_height", "value"):
             layer_height = container.getProperty("layer_height", "value")
         else:
             # Look for layer_height in the GlobalStack from material -> definition

cura/Machines/QualityChangesGroup.py

@@ -1,22 +1,27 @@
 # Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
 
+from typing import TYPE_CHECKING
+
 from UM.Application import Application
 from UM.ConfigurationErrorMessage import ConfigurationErrorMessage
 
 from .QualityGroup import QualityGroup
 
+if TYPE_CHECKING:
+    from cura.Machines.QualityNode import QualityNode
+
 
 class QualityChangesGroup(QualityGroup):
-    def __init__(self, name: str, quality_type: str, parent = None):
+    def __init__(self, name: str, quality_type: str, parent = None) -> None:
         super().__init__(name, quality_type, parent)
         self._container_registry = Application.getInstance().getContainerRegistry()
 
     def addNode(self, node: "QualityNode"):
-        extruder_position = node.metadata.get("position")
+        extruder_position = node.getMetaDataEntry("position")
 
         if extruder_position is None and self.node_for_global is not None or extruder_position in self.nodes_for_extruders: #We would be overwriting another node.
-            ConfigurationErrorMessage.getInstance().addFaultyContainers(node.metadata["id"])
+            ConfigurationErrorMessage.getInstance().addFaultyContainers(node.getMetaDataEntry("id"))
             return
 
         if extruder_position is None: #Then we're a global quality changes profile.

cura/Machines/QualityGroup.py

@@ -1,10 +1,10 @@
 # Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
 
-from typing import Dict, Optional, List
+from typing import Dict, Optional, List, Set
 
 from PyQt5.QtCore import QObject, pyqtSlot
-
+from cura.Machines.ContainerNode import ContainerNode
 
 #
 # A QualityGroup represents a group of containers that must be applied to each ContainerStack when it's used.
@@ -21,11 +21,11 @@ from PyQt5.QtCore import QObject, pyqtSlot
 #
 class QualityGroup(QObject):
 
-    def __init__(self, name: str, quality_type: str, parent = None):
+    def __init__(self, name: str, quality_type: str, parent = None) -> None:
         super().__init__(parent)
         self.name = name
-        self.node_for_global = None  # type: Optional["QualityGroup"]
+        self.node_for_global = None  # type: Optional[ContainerNode]
-        self.nodes_for_extruders = {}  # type: Dict[int, "QualityGroup"]
+        self.nodes_for_extruders = {}  # type: Dict[int, ContainerNode]
         self.quality_type = quality_type
         self.is_available = False
 
@@ -33,15 +33,17 @@ class QualityGroup(QObject):
     def getName(self) -> str:
         return self.name
 
-    def getAllKeys(self) -> set:
+    def getAllKeys(self) -> Set[str]:
-        result = set()
+        result = set() #type: Set[str]
         for node in [self.node_for_global] + list(self.nodes_for_extruders.values()):
             if node is None:
                 continue
-            result.update(node.getContainer().getAllKeys())
+            container = node.getContainer()
+            if container:
+                result.update(container.getAllKeys())
         return result
 
-    def getAllNodes(self) -> List["QualityGroup"]:
+    def getAllNodes(self) -> List[ContainerNode]:
         result = []
         if self.node_for_global is not None:
             result.append(self.node_for_global)

cura/Machines/QualityManager.py

@@ -1,7 +1,7 @@
 # Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
 
-from typing import TYPE_CHECKING, Optional
+from typing import TYPE_CHECKING, Optional, cast
 
 from PyQt5.QtCore import QObject, QTimer, pyqtSignal, pyqtSlot
 
@@ -90,7 +90,7 @@ class QualityManager(QObject):
 
             if definition_id not in self._machine_variant_material_quality_type_to_quality_dict:
                 self._machine_variant_material_quality_type_to_quality_dict[definition_id] = QualityNode()
-            machine_node = self._machine_variant_material_quality_type_to_quality_dict[definition_id]
+            machine_node = cast(QualityNode, self._machine_variant_material_quality_type_to_quality_dict[definition_id])
 
             if is_global_quality:
                 # For global qualities, save data in the machine node
@@ -102,7 +102,7 @@ class QualityManager(QObject):
                 # too.
                 if variant_name not in machine_node.children_map:
                     machine_node.children_map[variant_name] = QualityNode()
-                variant_node = machine_node.children_map[variant_name]
+                variant_node = cast(QualityNode, machine_node.children_map[variant_name])
 
                 if root_material_id is None:
                     # If only variant_name is specified but material is not, add the quality/quality_changes metadata
@@ -114,7 +114,7 @@ class QualityManager(QObject):
                     # material node.
                     if root_material_id not in variant_node.children_map:
                         variant_node.children_map[root_material_id] = QualityNode()
-                    material_node = variant_node.children_map[root_material_id]
+                    material_node = cast(QualityNode, variant_node.children_map[root_material_id])
 
                     material_node.addQualityMetadata(quality_type, metadata)
 
@@ -123,7 +123,7 @@ class QualityManager(QObject):
                 if root_material_id is not None:
                     if root_material_id not in machine_node.children_map:
                         machine_node.children_map[root_material_id] = QualityNode()
-                    material_node = machine_node.children_map[root_material_id]
+                    material_node = cast(QualityNode, machine_node.children_map[root_material_id])
 
                     material_node.addQualityMetadata(quality_type, metadata)
 
@@ -351,7 +351,7 @@ class QualityManager(QObject):
     def removeQualityChangesGroup(self, quality_changes_group: "QualityChangesGroup"):
         Logger.log("i", "Removing quality changes group [%s]", quality_changes_group.name)
         for node in quality_changes_group.getAllNodes():
-            self._container_registry.removeContainer(node.metadata["id"])
+            self._container_registry.removeContainer(node.getMetaDataEntry("id"))
 
     #
     # Rename a set of quality changes containers. Returns the new name.
@@ -365,7 +365,9 @@ class QualityManager(QObject):
 
         new_name = self._container_registry.uniqueName(new_name)
         for node in quality_changes_group.getAllNodes():
-            node.getContainer().setName(new_name)
+            container = node.getContainer()
+            if container:
+                container.setName(new_name)
 
         quality_changes_group.name = new_name
 

cura/Machines/QualityNode.py

@@ -1,7 +1,7 @@
 # Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
 
-from typing import Optional
+from typing import Optional, Dict, cast
 
 from .ContainerNode import ContainerNode
 from .QualityChangesGroup import QualityChangesGroup
@@ -12,9 +12,9 @@ from .QualityChangesGroup import QualityChangesGroup
 #
 class QualityNode(ContainerNode):
 
-    def __init__(self, metadata: Optional[dict] = None):
+    def __init__(self, metadata: Optional[dict] = None) -> None:
         super().__init__(metadata = metadata)
-        self.quality_type_map = {}  # quality_type -> QualityNode for InstanceContainer
+        self.quality_type_map = {}  # type: Dict[str, QualityNode] # quality_type -> QualityNode for InstanceContainer
 
     def addQualityMetadata(self, quality_type: str, metadata: dict):
         if quality_type not in self.quality_type_map:
@@ -32,4 +32,4 @@ class QualityNode(ContainerNode):
         if name not in quality_type_node.children_map:
             quality_type_node.children_map[name] = QualityChangesGroup(name, quality_type)
         quality_changes_group = quality_type_node.children_map[name]
-        quality_changes_group.addNode(QualityNode(metadata))
+        cast(QualityChangesGroup, quality_changes_group).addNode(QualityNode(metadata))

cura/PickingPass.py

@@ -1,6 +1,9 @@
 # Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
-from UM.Application import Application
+
+from typing import Optional, TYPE_CHECKING
+
+from UM.Qt.QtApplication import QtApplication
 from UM.Math.Vector import Vector
 from UM.Resources import Resources
 
@@ -10,19 +13,21 @@ from UM.View.RenderBatch import RenderBatch
 
 from UM.Scene.Iterator.DepthFirstIterator import DepthFirstIterator
 
+if TYPE_CHECKING:
+    from UM.View.GL.ShaderProgram import ShaderProgram
 
 ##  A RenderPass subclass that renders a the distance of selectable objects from the active camera to a texture.
 #   The texture is used to map a 2d location (eg the mouse location) to a world space position
 #
 #   Note that in order to increase precision, the 24 bit depth value is encoded into all three of the R,G & B channels
 class PickingPass(RenderPass):
-    def __init__(self, width: int, height: int):
+    def __init__(self, width: int, height: int) -> None:
         super().__init__("picking", width, height)
 
-        self._renderer = Application.getInstance().getRenderer()
+        self._renderer = QtApplication.getInstance().getRenderer()
 
-        self._shader = None
+        self._shader = None #type: Optional[ShaderProgram]
-        self._scene = Application.getInstance().getController().getScene()
+        self._scene = QtApplication.getInstance().getController().getScene()
 
     def render(self) -> None:
         if not self._shader:
@@ -37,7 +42,7 @@ class PickingPass(RenderPass):
         batch = RenderBatch(self._shader)
 
         # Fill up the batch with objects that can be sliced. `
-        for node in DepthFirstIterator(self._scene.getRoot()):
+        for node in DepthFirstIterator(self._scene.getRoot()): #type: ignore #Ignore type error because iter() should get called automatically by Python syntax.
             if node.callDecoration("isSliceable") and node.getMeshData() and node.isVisible():
                 batch.addItem(node.getWorldTransformation(), node.getMeshData())
 

cura/PreviewPass.py

@@ -1,5 +1,8 @@
 # Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
+
+from typing import Optional, TYPE_CHECKING
+
 from UM.Application import Application
 from UM.Resources import Resources
 
@@ -10,7 +13,8 @@ from UM.View.RenderBatch import RenderBatch
 
 from UM.Scene.Iterator.DepthFirstIterator import DepthFirstIterator
 
-from typing import Optional
+if TYPE_CHECKING:
+    from UM.View.GL.ShaderProgram import ShaderProgram
 
 MYPY = False
 if MYPY:
@@ -33,16 +37,16 @@ def prettier_color(color_list):
 #
 #   This is useful to get a preview image of a scene taken from a different location as the active camera.
 class PreviewPass(RenderPass):
-    def __init__(self, width: int, height: int):
+    def __init__(self, width: int, height: int) -> None:
         super().__init__("preview", width, height, 0)
 
         self._camera = None  # type: Optional[Camera]
 
         self._renderer = Application.getInstance().getRenderer()
 
-        self._shader = None
+        self._shader = None #type: Optional[ShaderProgram]
-        self._non_printing_shader = None
+        self._non_printing_shader = None #type: Optional[ShaderProgram]
-        self._support_mesh_shader = None
+        self._support_mesh_shader = None #type: Optional[ShaderProgram]
         self._scene = Application.getInstance().getController().getScene()
 
     #   Set the camera to be used by this render pass
@@ -53,20 +57,23 @@ class PreviewPass(RenderPass):
     def render(self) -> None:
         if not self._shader:
             self._shader = OpenGL.getInstance().createShaderProgram(Resources.getPath(Resources.Shaders, "overhang.shader"))
-            self._shader.setUniformValue("u_overhangAngle", 1.0)
+            if self._shader:
-            self._shader.setUniformValue("u_ambientColor", [0.1, 0.1, 0.1, 1.0])
+                self._shader.setUniformValue("u_overhangAngle", 1.0)
-            self._shader.setUniformValue("u_specularColor", [0.6, 0.6, 0.6, 1.0])
+                self._shader.setUniformValue("u_ambientColor", [0.1, 0.1, 0.1, 1.0])
-            self._shader.setUniformValue("u_shininess", 20.0)
+                self._shader.setUniformValue("u_specularColor", [0.6, 0.6, 0.6, 1.0])
+                self._shader.setUniformValue("u_shininess", 20.0)
 
         if not self._non_printing_shader:
-            self._non_printing_shader = OpenGL.getInstance().createShaderProgram(Resources.getPath(Resources.Shaders, "transparent_object.shader"))
+            if self._non_printing_shader:
-            self._non_printing_shader.setUniformValue("u_diffuseColor", [0.5, 0.5, 0.5, 0.5])
+                self._non_printing_shader = OpenGL.getInstance().createShaderProgram(Resources.getPath(Resources.Shaders, "transparent_object.shader"))
-            self._non_printing_shader.setUniformValue("u_opacity", 0.6)
+                self._non_printing_shader.setUniformValue("u_diffuseColor", [0.5, 0.5, 0.5, 0.5])
+                self._non_printing_shader.setUniformValue("u_opacity", 0.6)
 
         if not self._support_mesh_shader:
             self._support_mesh_shader = OpenGL.getInstance().createShaderProgram(Resources.getPath(Resources.Shaders, "striped.shader"))
-            self._support_mesh_shader.setUniformValue("u_vertical_stripes", True)
+            if self._support_mesh_shader:
-            self._support_mesh_shader.setUniformValue("u_width", 5.0)
+                self._support_mesh_shader.setUniformValue("u_vertical_stripes", True)
+                self._support_mesh_shader.setUniformValue("u_width", 5.0)
 
         self._gl.glClearColor(0.0, 0.0, 0.0, 0.0)
         self._gl.glClear(self._gl.GL_COLOR_BUFFER_BIT | self._gl.GL_DEPTH_BUFFER_BIT)
@@ -75,8 +82,8 @@ class PreviewPass(RenderPass):
         batch = RenderBatch(self._shader)
         batch_support_mesh = RenderBatch(self._support_mesh_shader)
 
-        # Fill up the batch with objects that can be sliced. `
+        # Fill up the batch with objects that can be sliced.
-        for node in DepthFirstIterator(self._scene.getRoot()):
+        for node in DepthFirstIterator(self._scene.getRoot()): #type: ignore #Ignore type error because iter() should get called automatically by Python syntax.
             if node.callDecoration("isSliceable") and node.getMeshData() and node.isVisible():
                 per_mesh_stack = node.callDecoration("getStack")
                 if node.callDecoration("isNonThumbnailVisibleMesh"):

cura/PrinterOutput/ExtruderOutputModel.py

@@ -4,10 +4,9 @@
 from PyQt5.QtCore import pyqtSignal, pyqtProperty, QObject, pyqtSlot
 from cura.PrinterOutput.ExtruderConfigurationModel import ExtruderConfigurationModel
 
-from typing import Optional
+from typing import Optional, TYPE_CHECKING
 
-MYPY = False
+if TYPE_CHECKING:
-if MYPY:
     from cura.PrinterOutput.PrinterOutputModel import PrinterOutputModel
     from cura.PrinterOutput.MaterialOutputModel import MaterialOutputModel
 
@@ -20,12 +19,12 @@ class ExtruderOutputModel(QObject):
     extruderConfigurationChanged = pyqtSignal()
     isPreheatingChanged = pyqtSignal()
 
-    def __init__(self, printer: "PrinterOutputModel", position, parent=None):
+    def __init__(self, printer: "PrinterOutputModel", position, parent=None) -> None:
         super().__init__(parent)
         self._printer = printer
         self._position = position
-        self._target_hotend_temperature = 0
+        self._target_hotend_temperature = 0 # type: float
-        self._hotend_temperature = 0
+        self._hotend_temperature = 0 # type: float
         self._hotend_id = ""
         self._active_material = None  # type: Optional[MaterialOutputModel]
         self._extruder_configuration = ExtruderConfigurationModel()
@@ -47,7 +46,7 @@ class ExtruderOutputModel(QObject):
         return False
 
     @pyqtProperty(QObject, notify = activeMaterialChanged)
-    def activeMaterial(self) -> "MaterialOutputModel":
+    def activeMaterial(self) -> Optional["MaterialOutputModel"]:
         return self._active_material
 
     def updateActiveMaterial(self, material: Optional["MaterialOutputModel"]):

cura/PrinterOutput/GenericOutputController.py

@@ -1,13 +1,15 @@
 # Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
 
+from typing import TYPE_CHECKING
+
 from cura.PrinterOutput.PrinterOutputController import PrinterOutputController
 from PyQt5.QtCore import QTimer
 
-MYPY = False
+if TYPE_CHECKING:
-if MYPY:
     from cura.PrinterOutput.PrintJobOutputModel import PrintJobOutputModel
     from cura.PrinterOutput.PrinterOutputModel import PrinterOutputModel
+    from cura.PrinterOutput.ExtruderOutputModel import ExtruderOutputModel
 
 
 class GenericOutputController(PrinterOutputController):

cura/PrinterOutput/NetworkedPrinterOutputDevice.py

@@ -1,17 +1,18 @@
 # Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
 
-from UM.Application import Application
+from UM.FileHandler.FileHandler import FileHandler #For typing.
 from UM.Logger import Logger
+from UM.Scene.SceneNode import SceneNode #For typing.
+from cura.CuraApplication import CuraApplication
 
 from cura.PrinterOutputDevice import PrinterOutputDevice, ConnectionState
 
-from PyQt5.QtNetwork import QHttpMultiPart, QHttpPart, QNetworkRequest, QNetworkAccessManager, QNetworkReply
+from PyQt5.QtNetwork import QHttpMultiPart, QHttpPart, QNetworkRequest, QNetworkAccessManager, QNetworkReply, QAuthenticator
-from PyQt5.QtCore import pyqtProperty, pyqtSignal, pyqtSlot, pyqtSignal, QUrl, QCoreApplication
+from PyQt5.QtCore import pyqtProperty, pyqtSignal, pyqtSlot, QObject, QUrl, QCoreApplication
 from time import time
-from typing import Callable, Any, Optional, Dict, Tuple
+from typing import Any, Callable, Dict, List, Optional
 from enum import IntEnum
-from typing import List
 
 import os  # To get the username
 import gzip
@@ -27,20 +28,20 @@ class AuthState(IntEnum):
 class NetworkedPrinterOutputDevice(PrinterOutputDevice):
     authenticationStateChanged = pyqtSignal()
 
-    def __init__(self, device_id, address: str, properties, parent = None) -> None:
+    def __init__(self, device_id, address: str, properties: Dict[bytes, bytes], parent: QObject = None) -> None:
         super().__init__(device_id = device_id, parent = parent)
-        self._manager = None    # type: QNetworkAccessManager
+        self._manager = None    # type: Optional[QNetworkAccessManager]
-        self._last_manager_create_time = None       # type: float
+        self._last_manager_create_time = None       # type: Optional[float]
         self._recreate_network_manager_time = 30
         self._timeout_time = 10  # After how many seconds of no response should a timeout occur?
 
-        self._last_response_time = None     # type: float
+        self._last_response_time = None     # type: Optional[float]
-        self._last_request_time = None      # type: float
+        self._last_request_time = None      # type: Optional[float]
 
         self._api_prefix = ""
         self._address = address
         self._properties = properties
-        self._user_agent = "%s/%s " % (Application.getInstance().getApplicationName(), Application.getInstance().getVersion())
+        self._user_agent = "%s/%s " % (CuraApplication.getInstance().getApplicationName(), CuraApplication.getInstance().getVersion())
 
         self._onFinishedCallbacks = {}      # type: Dict[str, Callable[[QNetworkReply], None]]
         self._authentication_state = AuthState.NotAuthenticated
@@ -67,16 +68,16 @@ class NetworkedPrinterOutputDevice(PrinterOutputDevice):
                 self._printer_type = value
                 break
 
-    def requestWrite(self, nodes, file_name=None, filter_by_machine=False, file_handler=None, **kwargs) -> None:
+    def requestWrite(self, nodes: List[SceneNode], file_name: Optional[str] = None, limit_mimetypes: bool = False, file_handler: Optional[FileHandler] = None, **kwargs: str) -> None:
         raise NotImplementedError("requestWrite needs to be implemented")
 
-    def setAuthenticationState(self, authentication_state) -> None:
+    def setAuthenticationState(self, authentication_state: AuthState) -> None:
         if self._authentication_state != authentication_state:
             self._authentication_state = authentication_state
             self.authenticationStateChanged.emit()
 
-    @pyqtProperty(int, notify=authenticationStateChanged)
+    @pyqtProperty(int, notify = authenticationStateChanged)
-    def authenticationState(self) -> int:
+    def authenticationState(self) -> AuthState:
         return self._authentication_state
 
     def _compressDataAndNotifyQt(self, data_to_append: str) -> bytes:
@@ -121,7 +122,7 @@ class NetworkedPrinterOutputDevice(PrinterOutputDevice):
         self._compressing_gcode = False
         return b"".join(file_data_bytes_list)
 
-    def _update(self) -> bool:
+    def _update(self) -> None:
         if self._last_response_time:
             time_since_last_response = time() - self._last_response_time
         else:
@@ -144,16 +145,16 @@ class NetworkedPrinterOutputDevice(PrinterOutputDevice):
             if time_since_last_response > self._recreate_network_manager_time:
                 if self._last_manager_create_time is None:
                     self._createNetworkManager()
-                if time() - self._last_manager_create_time > self._recreate_network_manager_time:
+                elif time() - self._last_manager_create_time > self._recreate_network_manager_time:
                     self._createNetworkManager()
+                assert(self._manager is not None)
         elif self._connection_state == ConnectionState.closed:
             # Go out of timeout.
-            self.setConnectionState(self._connection_state_before_timeout)
+            if self._connection_state_before_timeout is not None:   # sanity check, but it should never be None here
-            self._connection_state_before_timeout = None
+                self.setConnectionState(self._connection_state_before_timeout)
+                self._connection_state_before_timeout = None
 
-        return True
+    def _createEmptyRequest(self, target: str, content_type: Optional[str] = "application/json") -> QNetworkRequest:
-
-    def _createEmptyRequest(self, target, content_type: Optional[str] = "application/json") -> QNetworkRequest:
         url = QUrl("http://" + self._address + self._api_prefix + target)
         request = QNetworkRequest(url)
         if content_type is not None:
@@ -161,7 +162,7 @@ class NetworkedPrinterOutputDevice(PrinterOutputDevice):
         request.setHeader(QNetworkRequest.UserAgentHeader, self._user_agent)
         return request
 
-    def _createFormPart(self, content_header, data, content_type = None) -> QHttpPart:
+    def _createFormPart(self, content_header: str, data: bytes, content_type: Optional[str] = None) -> QHttpPart:
         part = QHttpPart()
 
         if not content_header.startswith("form-data;"):
@@ -187,33 +188,33 @@ class NetworkedPrinterOutputDevice(PrinterOutputDevice):
         if reply in self._kept_alive_multiparts:
             del self._kept_alive_multiparts[reply]
 
-    def put(self, target: str, data: str, onFinished: Optional[Callable[[Any, QNetworkReply], None]]) -> None:
+    def put(self, target: str, data: str, on_finished: Optional[Callable[[QNetworkReply], None]]) -> None:
         if self._manager is None:
             self._createNetworkManager()
         request = self._createEmptyRequest(target)
         self._last_request_time = time()
         reply = self._manager.put(request, data.encode())
-        self._registerOnFinishedCallback(reply, onFinished)
+        self._registerOnFinishedCallback(reply, on_finished)
 
-    def get(self, target: str, onFinished: Optional[Callable[[Any, QNetworkReply], None]]) -> None:
+    def get(self, target: str, on_finished: Optional[Callable[[QNetworkReply], None]]) -> None:
         if self._manager is None:
             self._createNetworkManager()
         request = self._createEmptyRequest(target)
         self._last_request_time = time()
         reply = self._manager.get(request)
-        self._registerOnFinishedCallback(reply, onFinished)
+        self._registerOnFinishedCallback(reply, on_finished)
 
-    def post(self, target: str, data: str, onFinished: Optional[Callable[[Any, QNetworkReply], None]], onProgress: Callable = None) -> None:
+    def post(self, target: str, data: str, on_finished: Optional[Callable[[QNetworkReply], None]], on_progress: Callable = None) -> None:
         if self._manager is None:
             self._createNetworkManager()
         request = self._createEmptyRequest(target)
         self._last_request_time = time()
         reply = self._manager.post(request, data)
-        if onProgress is not None:
+        if on_progress is not None:
-            reply.uploadProgress.connect(onProgress)
+            reply.uploadProgress.connect(on_progress)
-        self._registerOnFinishedCallback(reply, onFinished)
+        self._registerOnFinishedCallback(reply, on_finished)
 
-    def postFormWithParts(self, target:str, parts: List[QHttpPart], onFinished: Optional[Callable[[Any, QNetworkReply], None]], onProgress: Callable = None) -> None:
+    def postFormWithParts(self, target:str, parts: List[QHttpPart], on_finished: Optional[Callable[[QNetworkReply], None]], on_progress: Callable = None) -> QNetworkReply:
         if self._manager is None:
             self._createNetworkManager()
         request = self._createEmptyRequest(target, content_type=None)
@@ -227,20 +228,20 @@ class NetworkedPrinterOutputDevice(PrinterOutputDevice):
 
         self._kept_alive_multiparts[reply] = multi_post_part
 
-        if onProgress is not None:
+        if on_progress is not None:
-            reply.uploadProgress.connect(onProgress)
+            reply.uploadProgress.connect(on_progress)
-        self._registerOnFinishedCallback(reply, onFinished)
+        self._registerOnFinishedCallback(reply, on_finished)
 
         return reply
 
-    def postForm(self, target: str, header_data: str, body_data: bytes, onFinished: Optional[Callable[[Any, QNetworkReply], None]], onProgress: Callable = None) -> None:
+    def postForm(self, target: str, header_data: str, body_data: bytes, on_finished: Optional[Callable[[QNetworkReply], None]], on_progress: Callable = None) -> None:
         post_part = QHttpPart()
         post_part.setHeader(QNetworkRequest.ContentDispositionHeader, header_data)
         post_part.setBody(body_data)
 
-        self.postFormWithParts(target, [post_part], onFinished, onProgress)
+        self.postFormWithParts(target, [post_part], on_finished, on_progress)
 
-    def _onAuthenticationRequired(self, reply, authenticator) -> None:
+    def _onAuthenticationRequired(self, reply: QNetworkReply, authenticator: QAuthenticator) -> None:
         Logger.log("w", "Request to {url} required authentication, which was not implemented".format(url = reply.url().toString()))
 
     def _createNetworkManager(self) -> None:
@@ -255,11 +256,11 @@ class NetworkedPrinterOutputDevice(PrinterOutputDevice):
         self._manager.authenticationRequired.connect(self._onAuthenticationRequired)
 
         if self._properties.get(b"temporary", b"false") != b"true":
-            Application.getInstance().getMachineManager().checkCorrectGroupName(self.getId(), self.name)
+            CuraApplication.getInstance().getMachineManager().checkCorrectGroupName(self.getId(), self.name)
 
-    def _registerOnFinishedCallback(self, reply: QNetworkReply, onFinished: Optional[Callable[[Any, QNetworkReply], None]]) -> None:
+    def _registerOnFinishedCallback(self, reply: QNetworkReply, on_finished: Optional[Callable[[QNetworkReply], None]]) -> None:
-        if onFinished is not None:
+        if on_finished is not None:
-            self._onFinishedCallbacks[reply.url().toString() + str(reply.operation())] = onFinished
+            self._onFinishedCallbacks[reply.url().toString() + str(reply.operation())] = on_finished
 
     def __handleOnFinished(self, reply: QNetworkReply) -> None:
         # Due to garbage collection, we need to cache certain bits of post operations.
@@ -296,30 +297,30 @@ class NetworkedPrinterOutputDevice(PrinterOutputDevice):
 
     ##  Get the unique key of this machine
     #   \return key String containing the key of the machine.
-    @pyqtProperty(str, constant=True)
+    @pyqtProperty(str, constant = True)
     def key(self) -> str:
         return self._id
 
     ##  The IP address of the printer.
-    @pyqtProperty(str, constant=True)
+    @pyqtProperty(str, constant = True)
     def address(self) -> str:
         return self._properties.get(b"address", b"").decode("utf-8")
 
     ##  Name of the printer (as returned from the ZeroConf properties)
-    @pyqtProperty(str, constant=True)
+    @pyqtProperty(str, constant = True)
     def name(self) -> str:
         return self._properties.get(b"name", b"").decode("utf-8")
 
     ##  Firmware version (as returned from the ZeroConf properties)
-    @pyqtProperty(str, constant=True)
+    @pyqtProperty(str, constant = True)
     def firmwareVersion(self) -> str:
         return self._properties.get(b"firmware_version", b"").decode("utf-8")
 
-    @pyqtProperty(str, constant=True)
+    @pyqtProperty(str, constant = True)
     def printerType(self) -> str:
         return self._printer_type
 
-    ## IPadress of this printer
+    ## IP adress of this printer
-    @pyqtProperty(str, constant=True)
+    @pyqtProperty(str, constant = True)
     def ipAddress(self) -> str:
         return self._address

cura/PrinterOutput/PrintJobOutputModel.py

@@ -2,9 +2,9 @@
 # Cura is released under the terms of the LGPLv3 or higher.
 
 from PyQt5.QtCore import pyqtSignal, pyqtProperty, QObject, pyqtSlot
-from typing import Optional
+from typing import Optional, TYPE_CHECKING
-MYPY = False
+
-if MYPY:
+if TYPE_CHECKING:
     from cura.PrinterOutput.PrinterOutputController import PrinterOutputController
     from cura.PrinterOutput.PrinterOutputModel import PrinterOutputModel
 
@@ -18,7 +18,7 @@ class PrintJobOutputModel(QObject):
     assignedPrinterChanged = pyqtSignal()
     ownerChanged = pyqtSignal()
 
-    def __init__(self, output_controller: "PrinterOutputController", key: str = "", name: str = "", parent=None):
+    def __init__(self, output_controller: "PrinterOutputController", key: str = "", name: str = "", parent=None) -> None:
         super().__init__(parent)
         self._output_controller = output_controller
         self._state = ""

cura/PrinterOutput/PrinterOutputModel.py

@@ -27,7 +27,7 @@ class PrinterOutputModel(QObject):
     cameraChanged = pyqtSignal()
     configurationChanged = pyqtSignal()
 
-    def __init__(self, output_controller: "PrinterOutputController", number_of_extruders: int = 1, parent=None, firmware_version = ""):
+    def __init__(self, output_controller: "PrinterOutputController", number_of_extruders: int = 1, parent=None, firmware_version = "") -> None:
         super().__init__(parent)
         self._bed_temperature = -1  # Use -1 for no heated bed.
         self._target_bed_temperature = 0

cura/PrinterOutputDevice.py

@@ -1,17 +1,20 @@
 # Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
+
 from UM.Decorators import deprecated
 from UM.i18n import i18nCatalog
 from UM.OutputDevice.OutputDevice import OutputDevice
-from PyQt5.QtCore import pyqtProperty, QObject, QTimer, pyqtSignal, QVariant
+from PyQt5.QtCore import pyqtProperty, QObject, QTimer, pyqtSignal
 from PyQt5.QtWidgets import QMessageBox
 
 from UM.Logger import Logger
+from UM.FileHandler.FileHandler import FileHandler #For typing.
+from UM.Scene.SceneNode import SceneNode #For typing.
 from UM.Signal import signalemitter
-from UM.Application import Application
+from UM.Qt.QtApplication import QtApplication
 
 from enum import IntEnum  # For the connection state tracking.
-from typing import List, Optional
+from typing import Callable, List, Optional
 
 MYPY = False
 if MYPY:
@@ -20,6 +23,16 @@ if MYPY:
 
 i18n_catalog = i18nCatalog("cura")
 
+
+##  The current processing state of the backend.
+class ConnectionState(IntEnum):
+    closed = 0
+    connecting = 1
+    connected = 2
+    busy = 3
+    error = 4
+
+
 ##  Printer output device adds extra interface options on top of output device.
 #
 #   The assumption is made the printer is a FDM printer.
@@ -47,38 +60,37 @@ class PrinterOutputDevice(QObject, OutputDevice):
     # Signal to indicate that the configuration of one of the printers has changed.
     uniqueConfigurationsChanged = pyqtSignal()
 
-    def __init__(self, device_id, parent = None):
+    def __init__(self, device_id: str, parent: QObject = None) -> None:
         super().__init__(device_id = device_id, parent = parent)
 
         self._printers = []  # type: List[PrinterOutputModel]
         self._unique_configurations = []   # type: List[ConfigurationModel]
 
-        self._monitor_view_qml_path = ""
+        self._monitor_view_qml_path = "" #type: str
-        self._monitor_component = None
+        self._monitor_component = None #type: Optional[QObject]
-        self._monitor_item = None
+        self._monitor_item = None #type: Optional[QObject]
 
-        self._control_view_qml_path = ""
+        self._control_view_qml_path = "" #type: str
-        self._control_component = None
+        self._control_component = None #type: Optional[QObject]
-        self._control_item = None
+        self._control_item = None #type: Optional[QObject]
 
-        self._qml_context = None
+        self._accepts_commands = False #type: bool
-        self._accepts_commands = False
 
-        self._update_timer = QTimer()
+        self._update_timer = QTimer() #type: QTimer
         self._update_timer.setInterval(2000)  # TODO; Add preference for update interval
         self._update_timer.setSingleShot(False)
         self._update_timer.timeout.connect(self._update)
 
-        self._connection_state = ConnectionState.closed
+        self._connection_state = ConnectionState.closed #type: ConnectionState
 
-        self._firmware_name = None
+        self._firmware_name = None #type: Optional[str]
-        self._address = ""
+        self._address = "" #type: str
-        self._connection_text = ""
+        self._connection_text = "" #type: str
         self.printersChanged.connect(self._onPrintersChanged)
-        Application.getInstance().getOutputDeviceManager().outputDevicesChanged.connect(self._updateUniqueConfigurations)
+        QtApplication.getInstance().getOutputDeviceManager().outputDevicesChanged.connect(self._updateUniqueConfigurations)
 
     @pyqtProperty(str, notify = connectionTextChanged)
-    def address(self):
+    def address(self) -> str:
         return self._address
 
     def setConnectionText(self, connection_text):
@@ -87,36 +99,36 @@ class PrinterOutputDevice(QObject, OutputDevice):
             self.connectionTextChanged.emit()
 
     @pyqtProperty(str, constant=True)
-    def connectionText(self):
+    def connectionText(self) -> str:
         return self._connection_text
 
-    def materialHotendChangedMessage(self, callback):
+    def materialHotendChangedMessage(self, callback: Callable[[int], None]) -> None:
         Logger.log("w", "materialHotendChangedMessage needs to be implemented, returning 'Yes'")
         callback(QMessageBox.Yes)
 
-    def isConnected(self):
+    def isConnected(self) -> bool:
         return self._connection_state != ConnectionState.closed and self._connection_state != ConnectionState.error
 
-    def setConnectionState(self, connection_state):
+    def setConnectionState(self, connection_state: ConnectionState) -> None:
         if self._connection_state != connection_state:
             self._connection_state = connection_state
             self.connectionStateChanged.emit(self._id)
 
     @pyqtProperty(str, notify = connectionStateChanged)
-    def connectionState(self):
+    def connectionState(self) -> ConnectionState:
         return self._connection_state
 
-    def _update(self):
+    def _update(self) -> None:
         pass
 
-    def _getPrinterByKey(self, key) -> Optional["PrinterOutputModel"]:
+    def _getPrinterByKey(self, key: str) -> Optional["PrinterOutputModel"]:
         for printer in self._printers:
             if printer.key == key:
                 return printer
 
         return None
 
-    def requestWrite(self, nodes, file_name = None, filter_by_machine = False, file_handler = None, **kwargs):
+    def requestWrite(self, nodes: List[SceneNode], file_name: Optional[str] = None, limit_mimetypes: bool = False, file_handler: Optional[FileHandler] = None, **kwargs: str) -> None:
         raise NotImplementedError("requestWrite needs to be implemented")
 
     @pyqtProperty(QObject, notify = printersChanged)
@@ -126,11 +138,11 @@ class PrinterOutputDevice(QObject, OutputDevice):
         return None
 
     @pyqtProperty("QVariantList", notify = printersChanged)
-    def printers(self):
+    def printers(self) -> List["PrinterOutputModel"]:
         return self._printers
 
-    @pyqtProperty(QObject, constant=True)
+    @pyqtProperty(QObject, constant = True)
-    def monitorItem(self):
+    def monitorItem(self) -> QObject:
         # Note that we specifically only check if the monitor component is created.
         # It could be that it failed to actually create the qml item! If we check if the item was created, it will try to
         # create the item (and fail) every time.
@@ -138,49 +150,49 @@ class PrinterOutputDevice(QObject, OutputDevice):
             self._createMonitorViewFromQML()
         return self._monitor_item
 
-    @pyqtProperty(QObject, constant=True)
+    @pyqtProperty(QObject, constant = True)
-    def controlItem(self):
+    def controlItem(self) -> QObject:
         if not self._control_component:
             self._createControlViewFromQML()
         return self._control_item
 
-    def _createControlViewFromQML(self):
+    def _createControlViewFromQML(self) -> None:
         if not self._control_view_qml_path:
             return
         if self._control_item is None:
-            self._control_item = Application.getInstance().createQmlComponent(self._control_view_qml_path, {"OutputDevice": self})
+            self._control_item = QtApplication.getInstance().createQmlComponent(self._control_view_qml_path, {"OutputDevice": self})
 
-    def _createMonitorViewFromQML(self):
+    def _createMonitorViewFromQML(self) -> None:
         if not self._monitor_view_qml_path:
             return
 
         if self._monitor_item is None:
-            self._monitor_item = Application.getInstance().createQmlComponent(self._monitor_view_qml_path, {"OutputDevice": self})
+            self._monitor_item = QtApplication.getInstance().createQmlComponent(self._monitor_view_qml_path, {"OutputDevice": self})
 
     ##  Attempt to establish connection
-    def connect(self):
+    def connect(self) -> None:
         self.setConnectionState(ConnectionState.connecting)
         self._update_timer.start()
 
     ##  Attempt to close the connection
-    def close(self):
+    def close(self) -> None:
         self._update_timer.stop()
         self.setConnectionState(ConnectionState.closed)
 
     ##  Ensure that close gets called when object is destroyed
-    def __del__(self):
+    def __del__(self) -> None:
         self.close()
 
-    @pyqtProperty(bool, notify=acceptsCommandsChanged)
+    @pyqtProperty(bool, notify = acceptsCommandsChanged)
-    def acceptsCommands(self):
+    def acceptsCommands(self) -> bool:
         return self._accepts_commands
 
     @deprecated("Please use the protected function instead", "3.2")
-    def setAcceptsCommands(self, accepts_commands):
+    def setAcceptsCommands(self, accepts_commands: bool) -> None:
         self._setAcceptsCommands(accepts_commands)
 
     ##  Set a flag to signal the UI that the printer is not (yet) ready to receive commands
-    def _setAcceptsCommands(self, accepts_commands):
+    def _setAcceptsCommands(self, accepts_commands: bool) -> None:
         if self._accepts_commands != accepts_commands:
             self._accepts_commands = accepts_commands
 
@@ -188,15 +200,15 @@ class PrinterOutputDevice(QObject, OutputDevice):
 
     # Returns the unique configurations of the printers within this output device
     @pyqtProperty("QVariantList", notify = uniqueConfigurationsChanged)
-    def uniqueConfigurations(self):
+    def uniqueConfigurations(self) -> List["ConfigurationModel"]:
         return self._unique_configurations
 
-    def _updateUniqueConfigurations(self):
+    def _updateUniqueConfigurations(self) -> None:
         self._unique_configurations = list(set([printer.printerConfiguration for printer in self._printers if printer.printerConfiguration is not None]))
         self._unique_configurations.sort(key = lambda k: k.printerType)
         self.uniqueConfigurationsChanged.emit()
 
-    def _onPrintersChanged(self):
+    def _onPrintersChanged(self) -> None:
         for printer in self._printers:
             printer.configurationChanged.connect(self._updateUniqueConfigurations)
 
@@ -205,21 +217,12 @@ class PrinterOutputDevice(QObject, OutputDevice):
 
     ##  Set the device firmware name
     #
-    #   \param name \type{str} The name of the firmware.
+    #   \param name The name of the firmware.
-    def _setFirmwareName(self, name):
+    def _setFirmwareName(self, name: str) -> None:
         self._firmware_name = name
 
     ##  Get the name of device firmware
     #
     #   This name can be used to define device type
-    def getFirmwareName(self):
+    def getFirmwareName(self) -> Optional[str]:
-        return self._firmware_name
+        return self._firmware_name
-
-
-##  The current processing state of the backend.
-class ConnectionState(IntEnum):
-    closed = 0
-    connecting = 1
-    connected = 2
-    busy = 3
-    error = 4

cura/Scene/CuraSceneController.py

@@ -16,7 +16,7 @@ from UM.Signal import Signal
 class CuraSceneController(QObject):
     activeBuildPlateChanged = Signal()
 
-    def __init__(self, objects_model: ObjectsModel, multi_build_plate_model: MultiBuildPlateModel):
+    def __init__(self, objects_model: ObjectsModel, multi_build_plate_model: MultiBuildPlateModel) -> None:
         super().__init__()
 
         self._objects_model = objects_model

cura/Scene/CuraSceneNode.py

@@ -1,40 +1,47 @@
 # Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
+
 from copy import deepcopy
-from typing import List, Optional
+from typing import cast, Dict, List, Optional
 
 from UM.Application import Application
 from UM.Math.AxisAlignedBox import AxisAlignedBox
+from UM.Math.Polygon import Polygon #For typing.
 from UM.Scene.SceneNode import SceneNode
+from UM.Scene.SceneNodeDecorator import SceneNodeDecorator #To cast the deepcopy of every decorator back to SceneNodeDecorator.
 
-from cura.Settings.SettingOverrideDecorator import SettingOverrideDecorator
+import cura.CuraApplication #To get the build plate.
-
+from cura.Settings.ExtruderStack import ExtruderStack #For typing.
+from cura.Settings.SettingOverrideDecorator import SettingOverrideDecorator #For per-object settings.
 
 ##  Scene nodes that are models are only seen when selecting the corresponding build plate
 #   Note that many other nodes can just be UM SceneNode objects.
 class CuraSceneNode(SceneNode):
-    def __init__(self, parent: Optional["SceneNode"] = None, visible: bool = True, name: str = "", no_setting_override: bool = False):
+    def __init__(self, parent: Optional["SceneNode"] = None, visible: bool = True, name: str = "", no_setting_override: bool = False) -> None:
         super().__init__(parent = parent, visible = visible, name = name)
         if not no_setting_override:
             self.addDecorator(SettingOverrideDecorator())  # now we always have a getActiveExtruderPosition, unless explicitly disabled
         self._outside_buildarea = False
 
-    def setOutsideBuildArea(self, new_value):
+    def setOutsideBuildArea(self, new_value: bool) -> None:
         self._outside_buildarea = new_value
 
-    def isOutsideBuildArea(self):
+    def isOutsideBuildArea(self) -> bool:
         return self._outside_buildarea or self.callDecoration("getBuildPlateNumber") < 0
 
-    def isVisible(self):
+    def isVisible(self) -> bool:
-        return super().isVisible() and self.callDecoration("getBuildPlateNumber") == Application.getInstance().getMultiBuildPlateModel().activeBuildPlate
+        return super().isVisible() and self.callDecoration("getBuildPlateNumber") == cura.CuraApplication.CuraApplication.getInstance().getMultiBuildPlateModel().activeBuildPlate
 
     def isSelectable(self) -> bool:
-        return super().isSelectable() and self.callDecoration("getBuildPlateNumber") == Application.getInstance().getMultiBuildPlateModel().activeBuildPlate
+        return super().isSelectable() and self.callDecoration("getBuildPlateNumber") == cura.CuraApplication.CuraApplication.getInstance().getMultiBuildPlateModel().activeBuildPlate
 
     ##  Get the extruder used to print this node. If there is no active node, then the extruder in position zero is returned
     #   TODO The best way to do it is by adding the setActiveExtruder decorator to every node when is loaded
-    def getPrintingExtruder(self):
+    def getPrintingExtruder(self) -> Optional[ExtruderStack]:
         global_container_stack = Application.getInstance().getGlobalContainerStack()
+        if global_container_stack is None:
+            return None
+
         per_mesh_stack = self.callDecoration("getStack")
         extruders = list(global_container_stack.extruders.values())
 
@@ -79,17 +86,17 @@ class CuraSceneNode(SceneNode):
         ]
 
     ##  Return if the provided bbox collides with the bbox of this scene node
-    def collidesWithBbox(self, check_bbox):
+    def collidesWithBbox(self, check_bbox: AxisAlignedBox) -> bool:
         bbox = self.getBoundingBox()
-
+        if bbox is not None:
-        # Mark the node as outside the build volume if the bounding box test fails.
+            # Mark the node as outside the build volume if the bounding box test fails.
-        if check_bbox.intersectsBox(bbox) != AxisAlignedBox.IntersectionResult.FullIntersection:
+            if check_bbox.intersectsBox(bbox) != AxisAlignedBox.IntersectionResult.FullIntersection:
-            return True
+                return True
 
         return False
 
     ##  Return if any area collides with the convex hull of this scene node
-    def collidesWithArea(self, areas):
+    def collidesWithArea(self, areas: List[Polygon]) -> bool:
         convex_hull = self.callDecoration("getConvexHull")
         if convex_hull:
             if not convex_hull.isValid():
@@ -104,8 +111,7 @@ class CuraSceneNode(SceneNode):
         return False
 
     ##  Override of SceneNode._calculateAABB to exclude non-printing-meshes from bounding box
-    def _calculateAABB(self):
+    def _calculateAABB(self) -> None:
-        aabb = None
         if self._mesh_data:
             aabb = self._mesh_data.getExtents(self.getWorldTransformation())
         else:  # If there is no mesh_data, use a boundingbox that encompasses the local (0,0,0)
@@ -123,18 +129,18 @@ class CuraSceneNode(SceneNode):
         self._aabb = aabb
 
     ##  Taken from SceneNode, but replaced SceneNode with CuraSceneNode
-    def __deepcopy__(self, memo):
+    def __deepcopy__(self, memo: Dict[int, object]) -> "CuraSceneNode":
         copy = CuraSceneNode(no_setting_override = True)  # Setting override will be added later
         copy.setTransformation(self.getLocalTransformation())
         copy.setMeshData(self._mesh_data)
-        copy.setVisible(deepcopy(self._visible, memo))
+        copy.setVisible(cast(bool, deepcopy(self._visible, memo)))
-        copy._selectable = deepcopy(self._selectable, memo)
+        copy._selectable = cast(bool, deepcopy(self._selectable, memo))
-        copy._name = deepcopy(self._name, memo)
+        copy._name = cast(str, deepcopy(self._name, memo))
         for decorator in self._decorators:
-            copy.addDecorator(deepcopy(decorator, memo))
+            copy.addDecorator(cast(SceneNodeDecorator, deepcopy(decorator, memo)))
 
         for child in self._children:
-            copy.addChild(deepcopy(child, memo))
+            copy.addChild(cast(SceneNode, deepcopy(child, memo)))
         self.calculateBoundingBoxMesh()
         return copy
 

cura/Settings/ContainerManager.py

@@ -468,7 +468,7 @@ class ContainerManager(QObject):
         container_list = [n.getContainer() for n in quality_changes_group.getAllNodes() if n.getContainer() is not None]
         self._container_registry.exportQualityProfile(container_list, path, file_type)
 
-    __instance = None
+    __instance = None   # type: ContainerManager
 
     @classmethod
     def getInstance(cls, *args, **kwargs) -> "ContainerManager":

cura/Settings/CuraContainerRegistry.py

@@ -5,7 +5,7 @@ import os
 import re
 import configparser
 
-from typing import Optional
+from typing import cast, Optional
 
 from PyQt5.QtWidgets import QMessageBox
 
@@ -26,7 +26,7 @@ from UM.Resources import Resources
 from . import ExtruderStack
 from . import GlobalStack
 
-from cura.CuraApplication import CuraApplication
+import cura.CuraApplication
 from cura.Machines.QualityManager import getMachineDefinitionIDForQualitySearch
 from cura.ReaderWriters.ProfileReader import NoProfileException
 
@@ -57,7 +57,7 @@ class CuraContainerRegistry(ContainerRegistry):
 
         if isinstance(container, InstanceContainer) and type(container) != type(self.getEmptyInstanceContainer()):
             # Check against setting version of the definition.
-            required_setting_version = CuraApplication.SettingVersion
+            required_setting_version = cura.CuraApplication.CuraApplication.SettingVersion
             actual_setting_version = int(container.getMetaDataEntry("setting_version", default = 0))
             if required_setting_version != actual_setting_version:
                 Logger.log("w", "Instance container {container_id} is outdated. Its setting version is {actual_setting_version} but it should be {required_setting_version}.".format(container_id = container.getId(), actual_setting_version = actual_setting_version, required_setting_version = required_setting_version))
@@ -260,7 +260,7 @@ class CuraContainerRegistry(ContainerRegistry):
                         profile_id = ContainerRegistry.getInstance().uniqueName(global_stack.getId() + "_extruder_" + str(idx + 1))
                         profile = InstanceContainer(profile_id)
                         profile.setName(quality_name)
-                        profile.addMetaDataEntry("setting_version", CuraApplication.SettingVersion)
+                        profile.addMetaDataEntry("setting_version", cura.CuraApplication.CuraApplication.SettingVersion)
                         profile.addMetaDataEntry("type", "quality_changes")
                         profile.addMetaDataEntry("definition", expected_machine_definition)
                         profile.addMetaDataEntry("quality_type", quality_type)
@@ -356,13 +356,15 @@ class CuraContainerRegistry(ContainerRegistry):
             return catalog.i18nc("@info:status", "Profile is missing a quality type.")
 
         global_stack = Application.getInstance().getGlobalContainerStack()
+        if global_stack is None:
+            return None
         definition_id = getMachineDefinitionIDForQualitySearch(global_stack.definition)
         profile.setDefinition(definition_id)
 
         # Check to make sure the imported profile actually makes sense in context of the current configuration.
         # This prevents issues where importing a "draft" profile for a machine without "draft" qualities would report as
         # successfully imported but then fail to show up.
-        quality_manager = CuraApplication.getInstance()._quality_manager
+        quality_manager = cura.CuraApplication.CuraApplication.getInstance()._quality_manager
         quality_group_dict = quality_manager.getQualityGroupsForMachineDefinition(global_stack)
         if quality_type not in quality_group_dict:
             return catalog.i18nc("@info:status", "Could not find a quality type {0} for the current configuration.", quality_type)
@@ -465,7 +467,7 @@ class CuraContainerRegistry(ContainerRegistry):
     def addExtruderStackForSingleExtrusionMachine(self, machine, extruder_id, new_global_quality_changes = None, create_new_ids = True):
         new_extruder_id = extruder_id
 
-        application = CuraApplication.getInstance()
+        application = cura.CuraApplication.CuraApplication.getInstance()
 
         extruder_definitions = self.findDefinitionContainers(id = new_extruder_id)
         if not extruder_definitions:
@@ -485,7 +487,7 @@ class CuraContainerRegistry(ContainerRegistry):
         definition_changes_name = definition_changes_id
         definition_changes = InstanceContainer(definition_changes_id, parent = application)
         definition_changes.setName(definition_changes_name)
-        definition_changes.addMetaDataEntry("setting_version", CuraApplication.SettingVersion)
+        definition_changes.addMetaDataEntry("setting_version", application.SettingVersion)
         definition_changes.addMetaDataEntry("type", "definition_changes")
         definition_changes.addMetaDataEntry("definition", extruder_definition.getId())
 
@@ -514,7 +516,7 @@ class CuraContainerRegistry(ContainerRegistry):
         user_container.setName(user_container_name)
         user_container.addMetaDataEntry("type", "user")
         user_container.addMetaDataEntry("machine", machine.getId())
-        user_container.addMetaDataEntry("setting_version", CuraApplication.SettingVersion)
+        user_container.addMetaDataEntry("setting_version", application.SettingVersion)
         user_container.setDefinition(machine.definition.getId())
         user_container.setMetaDataEntry("position", extruder_stack.getMetaDataEntry("position"))
 
@@ -587,7 +589,7 @@ class CuraContainerRegistry(ContainerRegistry):
                     extruder_quality_changes_container = InstanceContainer(container_id, parent = application)
                     extruder_quality_changes_container.setName(container_name)
                     extruder_quality_changes_container.addMetaDataEntry("type", "quality_changes")
-                    extruder_quality_changes_container.addMetaDataEntry("setting_version", CuraApplication.SettingVersion)
+                    extruder_quality_changes_container.addMetaDataEntry("setting_version", application.SettingVersion)
                     extruder_quality_changes_container.addMetaDataEntry("position", extruder_definition.getMetaDataEntry("position"))
                     extruder_quality_changes_container.addMetaDataEntry("quality_type", machine_quality_changes.getMetaDataEntry("quality_type"))
                     extruder_quality_changes_container.setDefinition(machine_quality_changes.getDefinition().getId())
@@ -675,7 +677,7 @@ class CuraContainerRegistry(ContainerRegistry):
         return extruder_stack
 
     def _findQualityChangesContainerInCuraFolder(self, name):
-        quality_changes_dir = Resources.getPath(CuraApplication.ResourceTypes.QualityChangesInstanceContainer)
+        quality_changes_dir = Resources.getPath(cura.CuraApplication.CuraApplication.ResourceTypes.QualityChangesInstanceContainer)
 
         instance_container = None
 
@@ -731,3 +733,9 @@ class CuraContainerRegistry(ContainerRegistry):
                 extruder_stack.setNextStack(machines[0])
             else:
                 Logger.log("w", "Could not find machine {machine} for extruder {extruder}", machine = extruder_stack.getMetaDataEntry("machine"), extruder = extruder_stack.getId())
+
+    #Override just for the type.
+    @classmethod
+    @override(ContainerRegistry)
+    def getInstance(cls, *args, **kwargs) -> "CuraContainerRegistry":
+        return cast(CuraContainerRegistry, super().getInstance(*args, **kwargs))

cura/Settings/CuraContainerStack.py

@@ -1,15 +1,12 @@
-# Copyright (c) 2017 Ultimaker B.V.
+# Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
 
-import os.path
+from typing import Any, cast, List, Optional, Union
-
-from typing import Any, Optional
-
 from PyQt5.QtCore import pyqtProperty, pyqtSignal, QObject
-from UM.FlameProfiler import pyqtSlot
 
 from UM.Application import Application
 from UM.Decorators import override
+from UM.FlameProfiler import pyqtSlot
 from UM.Logger import Logger
 from UM.Settings.ContainerStack import ContainerStack, InvalidContainerStackError
 from UM.Settings.InstanceContainer import InstanceContainer
@@ -39,19 +36,19 @@ from . import Exceptions
 #   This also means that operations on the stack that modifies the container ordering is prohibited and
 #   will raise an exception.
 class CuraContainerStack(ContainerStack):
-    def __init__(self, container_id: str):
+    def __init__(self, container_id: str) -> None:
         super().__init__(container_id)
 
-        self._container_registry = ContainerRegistry.getInstance()
+        self._container_registry = ContainerRegistry.getInstance() #type: ContainerRegistry
 
-        self._empty_instance_container = self._container_registry.getEmptyInstanceContainer()
+        self._empty_instance_container = self._container_registry.getEmptyInstanceContainer() #type: InstanceContainer
 
-        self._empty_quality_changes = self._container_registry.findInstanceContainers(id = "empty_quality_changes")[0]
+        self._empty_quality_changes = self._container_registry.findInstanceContainers(id = "empty_quality_changes")[0] #type: InstanceContainer
-        self._empty_quality = self._container_registry.findInstanceContainers(id = "empty_quality")[0]
+        self._empty_quality = self._container_registry.findInstanceContainers(id = "empty_quality")[0] #type: InstanceContainer
-        self._empty_material = self._container_registry.findInstanceContainers(id = "empty_material")[0]
+        self._empty_material = self._container_registry.findInstanceContainers(id = "empty_material")[0] #type: InstanceContainer
-        self._empty_variant = self._container_registry.findInstanceContainers(id = "empty_variant")[0]
+        self._empty_variant = self._container_registry.findInstanceContainers(id = "empty_variant")[0] #type: InstanceContainer
 
-        self._containers = [self._empty_instance_container for i in range(len(_ContainerIndexes.IndexTypeMap))]
+        self._containers = [self._empty_instance_container for i in range(len(_ContainerIndexes.IndexTypeMap))] #type: List[Union[InstanceContainer, DefinitionContainer]]
         self._containers[_ContainerIndexes.QualityChanges] = self._empty_quality_changes
         self._containers[_ContainerIndexes.Quality] = self._empty_quality
         self._containers[_ContainerIndexes.Material] = self._empty_material
@@ -76,7 +73,7 @@ class CuraContainerStack(ContainerStack):
     #   \return The user changes container. Should always be a valid container, but can be equal to the empty InstanceContainer.
     @pyqtProperty(InstanceContainer, fset = setUserChanges, notify = pyqtContainersChanged)
     def userChanges(self) -> InstanceContainer:
-        return self._containers[_ContainerIndexes.UserChanges]
+        return cast(InstanceContainer, self._containers[_ContainerIndexes.UserChanges])
 
     ##  Set the quality changes container.
     #
@@ -89,12 +86,12 @@ class CuraContainerStack(ContainerStack):
     #   \return The quality changes container. Should always be a valid container, but can be equal to the empty InstanceContainer.
     @pyqtProperty(InstanceContainer, fset = setQualityChanges, notify = pyqtContainersChanged)
     def qualityChanges(self) -> InstanceContainer:
-        return self._containers[_ContainerIndexes.QualityChanges]
+        return cast(InstanceContainer, self._containers[_ContainerIndexes.QualityChanges])
 
     ##  Set the quality container.
     #
     #   \param new_quality The new quality container. It is expected to have a "type" metadata entry with the value "quality".
-    def setQuality(self, new_quality: InstanceContainer, postpone_emit = False) -> None:
+    def setQuality(self, new_quality: InstanceContainer, postpone_emit: bool = False) -> None:
         self.replaceContainer(_ContainerIndexes.Quality, new_quality, postpone_emit = postpone_emit)
 
     ##  Get the quality container.
@@ -102,12 +99,12 @@ class CuraContainerStack(ContainerStack):
     #   \return The quality container. Should always be a valid container, but can be equal to the empty InstanceContainer.
     @pyqtProperty(InstanceContainer, fset = setQuality, notify = pyqtContainersChanged)
     def quality(self) -> InstanceContainer:
-        return self._containers[_ContainerIndexes.Quality]
+        return cast(InstanceContainer, self._containers[_ContainerIndexes.Quality])
 
     ##  Set the material container.
     #
     #   \param new_material The new material container. It is expected to have a "type" metadata entry with the value "material".
-    def setMaterial(self, new_material: InstanceContainer, postpone_emit = False) -> None:
+    def setMaterial(self, new_material: InstanceContainer, postpone_emit: bool = False) -> None:
         self.replaceContainer(_ContainerIndexes.Material, new_material, postpone_emit = postpone_emit)
 
     ##  Get the material container.
@@ -115,7 +112,7 @@ class CuraContainerStack(ContainerStack):
     #   \return The material container. Should always be a valid container, but can be equal to the empty InstanceContainer.
     @pyqtProperty(InstanceContainer, fset = setMaterial, notify = pyqtContainersChanged)
     def material(self) -> InstanceContainer:
-        return self._containers[_ContainerIndexes.Material]
+        return cast(InstanceContainer, self._containers[_ContainerIndexes.Material])
 
     ##  Set the variant container.
     #
@@ -128,7 +125,7 @@ class CuraContainerStack(ContainerStack):
     #   \return The variant container. Should always be a valid container, but can be equal to the empty InstanceContainer.
     @pyqtProperty(InstanceContainer, fset = setVariant, notify = pyqtContainersChanged)
     def variant(self) -> InstanceContainer:
-        return self._containers[_ContainerIndexes.Variant]
+        return cast(InstanceContainer, self._containers[_ContainerIndexes.Variant])
 
     ##  Set the definition changes container.
     #
@@ -141,7 +138,7 @@ class CuraContainerStack(ContainerStack):
     #   \return The definition changes container. Should always be a valid container, but can be equal to the empty InstanceContainer.
     @pyqtProperty(InstanceContainer, fset = setDefinitionChanges, notify = pyqtContainersChanged)
     def definitionChanges(self) -> InstanceContainer:
-        return self._containers[_ContainerIndexes.DefinitionChanges]
+        return cast(InstanceContainer, self._containers[_ContainerIndexes.DefinitionChanges])
 
     ##  Set the definition container.
     #
@@ -154,7 +151,7 @@ class CuraContainerStack(ContainerStack):
     #   \return The definition container. Should always be a valid container, but can be equal to the empty InstanceContainer.
     @pyqtProperty(QObject, fset = setDefinition, notify = pyqtContainersChanged)
     def definition(self) -> DefinitionContainer:
-        return self._containers[_ContainerIndexes.Definition]
+        return cast(DefinitionContainer, self._containers[_ContainerIndexes.Definition])
 
     @override(ContainerStack)
     def getBottom(self) -> "DefinitionContainer":
@@ -189,13 +186,9 @@ class CuraContainerStack(ContainerStack):
     #   \param key The key of the setting to set.
     #   \param property_name The name of the property to set.
     #   \param new_value The new value to set the property to.
-    #   \param target_container The type of the container to set the property of. Defaults to "user".
+    def setProperty(self, key: str, property_name: str, property_value: Any, container: "ContainerInterface" = None, set_from_cache: bool = False) -> None:
-    def setProperty(self, key: str, property_name: str, new_value: Any, target_container: str = "user") -> None:
+        container_index = _ContainerIndexes.UserChanges
-        container_index = _ContainerIndexes.TypeIndexMap.get(target_container, -1)
+        self._containers[container_index].setProperty(key, property_name, property_value, container, set_from_cache)
-        if container_index != -1:
-            self._containers[container_index].setProperty(key, property_name, new_value)
-        else:
-            raise IndexError("Invalid target container {type}".format(type = target_container))
 
     ##  Overridden from ContainerStack
     #
@@ -310,15 +303,15 @@ class CuraContainerStack(ContainerStack):
     #
     #   \return The ID of the definition container to use when searching for instance containers.
     @classmethod
-    def _findInstanceContainerDefinitionId(cls, machine_definition: DefinitionContainer) -> str:
+    def _findInstanceContainerDefinitionId(cls, machine_definition: DefinitionContainerInterface) -> str:
         quality_definition = machine_definition.getMetaDataEntry("quality_definition")
         if not quality_definition:
-            return machine_definition.id
+            return machine_definition.id #type: ignore
 
         definitions = ContainerRegistry.getInstance().findDefinitionContainers(id = quality_definition)
         if not definitions:
-            Logger.log("w", "Unable to find parent definition {parent} for machine {machine}", parent = quality_definition, machine = machine_definition.id)
+            Logger.log("w", "Unable to find parent definition {parent} for machine {machine}", parent = quality_definition, machine = machine_definition.id) #type: ignore
-            return machine_definition.id
+            return machine_definition.id #type: ignore
 
         return cls._findInstanceContainerDefinitionId(definitions[0])
 

cura/Settings/ExtruderManager.py

@@ -1,10 +1,10 @@
-# Copyright (c) 2017 Ultimaker B.V.
+# Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
 
 from PyQt5.QtCore import pyqtSignal, pyqtProperty, QObject, QVariant  # For communicating data and events to Qt.
 from UM.FlameProfiler import pyqtSlot
 
-from UM.Application import Application  # To get the global container stack to find the current machine.
+import cura.CuraApplication #To get the global container stack to find the current machine.
 from UM.Logger import Logger
 from UM.Scene.Iterator.DepthFirstIterator import DepthFirstIterator
 from UM.Scene.SceneNode import SceneNode
@@ -16,7 +16,7 @@ from UM.Settings.SettingInstance import SettingInstance
 from UM.Settings.ContainerStack import ContainerStack
 from UM.Settings.PropertyEvaluationContext import PropertyEvaluationContext
 
-from typing import Optional, List, TYPE_CHECKING, Union
+from typing import Optional, List, TYPE_CHECKING, Union, Dict
 
 if TYPE_CHECKING:
     from cura.Settings.ExtruderStack import ExtruderStack
@@ -36,14 +36,13 @@ class ExtruderManager(QObject):
 
         super().__init__(parent)
 
-        self._application = Application.getInstance()
+        self._application = cura.CuraApplication.CuraApplication.getInstance()
 
         self._extruder_trains = {}  # Per machine, a dictionary of extruder container stack IDs. Only for separately defined extruders.
         self._active_extruder_index = -1  # Indicates the index of the active extruder stack. -1 means no active extruder stack
         self._selected_object_extruders = []
         self._addCurrentMachineExtruders()
 
-        #Application.getInstance().globalContainerStackChanged.connect(self._globalContainerStackChanged)
         Selection.selectionChanged.connect(self.resetSelectedObjectExtruders)
 
     ##  Signal to notify other components when the list of extruders for a machine definition changes.
@@ -60,42 +59,47 @@ class ExtruderManager(QObject):
     #   \return The unique ID of the currently active extruder stack.
     @pyqtProperty(str, notify = activeExtruderChanged)
     def activeExtruderStackId(self) -> Optional[str]:
-        if not Application.getInstance().getGlobalContainerStack():
+        if not self._application.getGlobalContainerStack():
             return None  # No active machine, so no active extruder.
         try:
-            return self._extruder_trains[Application.getInstance().getGlobalContainerStack().getId()][str(self._active_extruder_index)].getId()
+            return self._extruder_trains[self._application.getGlobalContainerStack().getId()][str(self._active_extruder_index)].getId()
         except KeyError:  # Extruder index could be -1 if the global tab is selected, or the entry doesn't exist if the machine definition is wrong.
             return None
 
     ##  Return extruder count according to extruder trains.
     @pyqtProperty(int, notify = extrudersChanged)
     def extruderCount(self):
-        if not Application.getInstance().getGlobalContainerStack():
+        if not self._application.getGlobalContainerStack():
             return 0  # No active machine, so no extruders.
         try:
-            return len(self._extruder_trains[Application.getInstance().getGlobalContainerStack().getId()])
+            return len(self._extruder_trains[self._application.getGlobalContainerStack().getId()])
         except KeyError:
             return 0
 
     ##  Gets a dict with the extruder stack ids with the extruder number as the key.
     @pyqtProperty("QVariantMap", notify = extrudersChanged)
-    def extruderIds(self):
+    def extruderIds(self) -> Dict[str, str]:
         extruder_stack_ids = {}
 
-        global_stack_id = Application.getInstance().getGlobalContainerStack().getId()
+        global_container_stack = self._application.getGlobalContainerStack()
+        if global_container_stack:
+            global_stack_id = global_container_stack.getId()
 
-        if global_stack_id in self._extruder_trains:
+            if global_stack_id in self._extruder_trains:
-            for position in self._extruder_trains[global_stack_id]:
+                for position in self._extruder_trains[global_stack_id]:
-                extruder_stack_ids[position] = self._extruder_trains[global_stack_id][position].getId()
+                    extruder_stack_ids[position] = self._extruder_trains[global_stack_id][position].getId()
 
         return extruder_stack_ids
 
     @pyqtSlot(str, result = str)
     def getQualityChangesIdByExtruderStackId(self, extruder_stack_id: str) -> str:
-        for position in self._extruder_trains[Application.getInstance().getGlobalContainerStack().getId()]:
+        global_container_stack = self._application.getGlobalContainerStack()
-            extruder = self._extruder_trains[Application.getInstance().getGlobalContainerStack().getId()][position]
+        if global_container_stack is not None:
-            if extruder.getId() == extruder_stack_id:
+            for position in self._extruder_trains[global_container_stack.getId()]:
-                return extruder.qualityChanges.getId()
+                extruder = self._extruder_trains[global_container_stack.getId()][position]
+                if extruder.getId() == extruder_stack_id:
+                    return extruder.qualityChanges.getId()
+        return ""
 
     ##  Changes the active extruder by index.
     #
@@ -132,7 +136,7 @@ class ExtruderManager(QObject):
             selected_nodes = []
             for node in Selection.getAllSelectedObjects():
                 if node.callDecoration("isGroup"):
-                    for grouped_node in BreadthFirstIterator(node):
+                    for grouped_node in BreadthFirstIterator(node): #type: ignore #Ignore type error because iter() should get called automatically by Python syntax.
                         if grouped_node.callDecoration("isGroup"):
                             continue
 
@@ -141,7 +145,7 @@ class ExtruderManager(QObject):
                     selected_nodes.append(node)
 
             # Then, figure out which nodes are used by those selected nodes.
-            global_stack = Application.getInstance().getGlobalContainerStack()
+            global_stack = self._application.getGlobalContainerStack()
             current_extruder_trains = self._extruder_trains.get(global_stack.getId())
             for node in selected_nodes:
                 extruder = node.callDecoration("getActiveExtruder")
@@ -164,7 +168,7 @@ class ExtruderManager(QObject):
 
     @pyqtSlot(result = QObject)
     def getActiveExtruderStack(self) -> Optional["ExtruderStack"]:
-        global_container_stack = Application.getInstance().getGlobalContainerStack()
+        global_container_stack = self._application.getGlobalContainerStack()
 
         if global_container_stack:
             if global_container_stack.getId() in self._extruder_trains:
@@ -175,7 +179,7 @@ class ExtruderManager(QObject):
 
     ##  Get an extruder stack by index
     def getExtruderStack(self, index) -> Optional["ExtruderStack"]:
-        global_container_stack = Application.getInstance().getGlobalContainerStack()
+        global_container_stack = self._application.getGlobalContainerStack()
         if global_container_stack:
             if global_container_stack.getId() in self._extruder_trains:
                 if str(index) in self._extruder_trains[global_container_stack.getId()]:
@@ -186,7 +190,9 @@ class ExtruderManager(QObject):
     def getExtruderStacks(self) -> List["ExtruderStack"]:
         result = []
         for i in range(self.extruderCount):
-            result.append(self.getExtruderStack(i))
+            stack = self.getExtruderStack(i)
+            if stack:
+                result.append(stack)
         return result
 
     def registerExtruder(self, extruder_train, machine_id):
@@ -252,14 +258,14 @@ class ExtruderManager(QObject):
         support_bottom_enabled = False
         support_roof_enabled = False
 
-        scene_root = Application.getInstance().getController().getScene().getRoot()
+        scene_root = self._application.getController().getScene().getRoot()
 
         # If no extruders are registered in the extruder manager yet, return an empty array
         if len(self.extruderIds) == 0:
             return []
 
         # Get the extruders of all printable meshes in the scene
-        meshes = [node for node in DepthFirstIterator(scene_root) if isinstance(node, SceneNode) and node.isSelectable()]
+        meshes = [node for node in DepthFirstIterator(scene_root) if isinstance(node, SceneNode) and node.isSelectable()] #type: ignore #Ignore type error because iter() should get called automatically by Python syntax.
         for mesh in meshes:
             extruder_stack_id = mesh.callDecoration("getActiveExtruder")
             if not extruder_stack_id:
@@ -301,10 +307,10 @@ class ExtruderManager(QObject):
 
         # The platform adhesion extruder. Not used if using none.
         if global_stack.getProperty("adhesion_type", "value") != "none":
-            extruder_nr = str(global_stack.getProperty("adhesion_extruder_nr", "value"))
+            extruder_str_nr = str(global_stack.getProperty("adhesion_extruder_nr", "value"))
-            if extruder_nr == "-1":
+            if extruder_str_nr == "-1":
-                extruder_nr = Application.getInstance().getMachineManager().defaultExtruderPosition
+                extruder_str_nr = self._application.getMachineManager().defaultExtruderPosition
-            used_extruder_stack_ids.add(self.extruderIds[extruder_nr])
+            used_extruder_stack_ids.add(self.extruderIds[extruder_str_nr])
 
         try:
             return [container_registry.findContainerStacks(id = stack_id)[0] for stack_id in used_extruder_stack_ids]
@@ -335,7 +341,7 @@ class ExtruderManager(QObject):
     #   The first element is the global container stack, followed by any extruder stacks.
     #   \return \type{List[ContainerStack]}
     def getActiveGlobalAndExtruderStacks(self) -> Optional[List[Union["ExtruderStack", "GlobalStack"]]]:
-        global_stack = Application.getInstance().getGlobalContainerStack()
+        global_stack = self._application.getGlobalContainerStack()
         if not global_stack:
             return None
 
@@ -347,7 +353,7 @@ class ExtruderManager(QObject):
     #
     #   \return \type{List[ContainerStack]} a list of
     def getActiveExtruderStacks(self) -> List["ExtruderStack"]:
-        global_stack = Application.getInstance().getGlobalContainerStack()
+        global_stack = self._application.getGlobalContainerStack()
         if not global_stack:
             return []
 
@@ -471,7 +477,7 @@ class ExtruderManager(QObject):
     #           If no extruder has the value, the list will contain the global value.
     @staticmethod
     def getExtruderValues(key):
-        global_stack = Application.getInstance().getGlobalContainerStack()
+        global_stack = cura.CuraApplication.CuraApplication.getInstance().getGlobalContainerStack()
 
         result = []
         for extruder in ExtruderManager.getInstance().getMachineExtruders(global_stack.getId()):
@@ -506,7 +512,7 @@ class ExtruderManager(QObject):
     #           If no extruder has the value, the list will contain the global value.
     @staticmethod
     def getDefaultExtruderValues(key):
-        global_stack = Application.getInstance().getGlobalContainerStack()
+        global_stack = cura.CuraApplication.CuraApplication.getInstance().getGlobalContainerStack()
         context = PropertyEvaluationContext(global_stack)
         context.context["evaluate_from_container_index"] = 1  # skip the user settings container
         context.context["override_operators"] = {
@@ -539,7 +545,7 @@ class ExtruderManager(QObject):
     ##  Return the default extruder position from the machine manager
     @staticmethod
     def getDefaultExtruderPosition() -> str:
-        return Application.getInstance().getMachineManager().defaultExtruderPosition
+        return cura.CuraApplication.CuraApplication.getInstance().getMachineManager().defaultExtruderPosition
 
     ##  Get all extruder values for a certain setting.
     #
@@ -564,7 +570,7 @@ class ExtruderManager(QObject):
     @staticmethod
     def getExtruderValue(extruder_index, key):
         if extruder_index == -1:
-            extruder_index = int(Application.getInstance().getMachineManager().defaultExtruderPosition)
+            extruder_index = int(cura.CuraApplication.CuraApplication.getInstance().getMachineManager().defaultExtruderPosition)
         extruder = ExtruderManager.getInstance().getExtruderStack(extruder_index)
 
         if extruder:
@@ -573,7 +579,7 @@ class ExtruderManager(QObject):
                 value = value(extruder)
         else:
             # Just a value from global.
-            value = Application.getInstance().getGlobalContainerStack().getProperty(key, "value")
+            value = cura.CuraApplication.CuraApplication.getInstance().getGlobalContainerStack().getProperty(key, "value")
 
         return value
 
@@ -602,7 +608,7 @@ class ExtruderManager(QObject):
             if isinstance(value, SettingFunction):
                 value = value(extruder, context = context)
         else:  # Just a value from global.
-            value = Application.getInstance().getGlobalContainerStack().getProperty(key, "value", context = context)
+            value = cura.CuraApplication.CuraApplication.getInstance().getGlobalContainerStack().getProperty(key, "value", context = context)
 
         return value
 
@@ -615,7 +621,7 @@ class ExtruderManager(QObject):
     #   \return The effective value
     @staticmethod
     def getResolveOrValue(key):
-        global_stack = Application.getInstance().getGlobalContainerStack()
+        global_stack = cura.CuraApplication.CuraApplication.getInstance().getGlobalContainerStack()
         resolved_value = global_stack.getProperty(key, "value")
 
         return resolved_value
@@ -629,7 +635,7 @@ class ExtruderManager(QObject):
     #   \return The effective value
     @staticmethod
     def getDefaultResolveOrValue(key):
-        global_stack = Application.getInstance().getGlobalContainerStack()
+        global_stack = cura.CuraApplication.CuraApplication.getInstance().getGlobalContainerStack()
         context = PropertyEvaluationContext(global_stack)
         context.context["evaluate_from_container_index"] = 1  # skip the user settings container
         context.context["override_operators"] = {
@@ -642,7 +648,7 @@ class ExtruderManager(QObject):
 
         return resolved_value
 
-    __instance = None
+    __instance = None   # type: ExtruderManager
 
     @classmethod
     def getInstance(cls, *args, **kwargs) -> "ExtruderManager":

cura/Settings/ExtruderStack.py

@@ -1,11 +1,10 @@
-# Copyright (c) 2017 Ultimaker B.V.
+# Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
 
-from typing import Any, TYPE_CHECKING, Optional
+from typing import Any, Dict, TYPE_CHECKING, Optional
 
 from PyQt5.QtCore import pyqtProperty, pyqtSignal
 
-from UM.Application import Application
 from UM.Decorators import override
 from UM.MimeTypeDatabase import MimeType, MimeTypeDatabase
 from UM.Settings.ContainerStack import ContainerStack
@@ -13,6 +12,8 @@ from UM.Settings.ContainerRegistry import ContainerRegistry
 from UM.Settings.Interfaces import ContainerInterface, PropertyEvaluationContext
 from UM.Util import parseBool
 
+import cura.CuraApplication
+
 from . import Exceptions
 from .CuraContainerStack import CuraContainerStack, _ContainerIndexes
 from .ExtruderManager import ExtruderManager
@@ -25,7 +26,7 @@ if TYPE_CHECKING:
 #
 #
 class ExtruderStack(CuraContainerStack):
-    def __init__(self, container_id: str):
+    def __init__(self, container_id: str) -> None:
         super().__init__(container_id)
 
         self.addMetaDataEntry("type", "extruder_train") # For backward compatibility
@@ -50,14 +51,14 @@ class ExtruderStack(CuraContainerStack):
     def getNextStack(self) -> Optional["GlobalStack"]:
         return super().getNextStack()
 
-    def setEnabled(self, enabled):
+    def setEnabled(self, enabled: bool) -> None:
         if "enabled" not in self._metadata:
             self.addMetaDataEntry("enabled", "True")
         self.setMetaDataEntry("enabled", str(enabled))
         self.enabledChanged.emit()
 
     @pyqtProperty(bool, notify = enabledChanged)
-    def isEnabled(self):
+    def isEnabled(self) -> bool:
         return parseBool(self.getMetaDataEntry("enabled", "True"))
 
     @classmethod
@@ -113,7 +114,7 @@ class ExtruderStack(CuraContainerStack):
         limit_to_extruder = super().getProperty(key, "limit_to_extruder", context)
         if limit_to_extruder is not None:
             if limit_to_extruder == -1:
-                limit_to_extruder = int(Application.getInstance().getMachineManager().defaultExtruderPosition)
+                limit_to_extruder = int(cura.CuraApplication.CuraApplication.getInstance().getMachineManager().defaultExtruderPosition)
             limit_to_extruder = str(limit_to_extruder)
         if (limit_to_extruder is not None and limit_to_extruder != "-1") and self.getMetaDataEntry("position") != str(limit_to_extruder):
             if str(limit_to_extruder) in self.getNextStack().extruders:
@@ -142,7 +143,7 @@ class ExtruderStack(CuraContainerStack):
         if stacks:
             self.setNextStack(stacks[0])
 
-    def _onPropertiesChanged(self, key, properties):
+    def _onPropertiesChanged(self, key: str, properties: Dict[str, Any]) -> None:
         # When there is a setting that is not settable per extruder that depends on a value from a setting that is,
         # we do not always get properly informed that we should re-evaluate the setting. So make sure to indicate
         # something changed for those settings.

cura/Settings/GlobalStack.py

@@ -1,29 +1,30 @@
-# Copyright (c) 2017 Ultimaker B.V.
+# Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
 
 from collections import defaultdict
 import threading
-from typing import Any, Dict, Optional
+from typing import Any, Dict, Optional, Set, TYPE_CHECKING
-
 from PyQt5.QtCore import pyqtProperty
 
-from UM.Application import Application
 from UM.Decorators import override
-
 from UM.MimeTypeDatabase import MimeType, MimeTypeDatabase
 from UM.Settings.ContainerStack import ContainerStack
 from UM.Settings.SettingInstance import InstanceState
 from UM.Settings.ContainerRegistry import ContainerRegistry
 from UM.Settings.Interfaces import PropertyEvaluationContext
 from UM.Logger import Logger
+import cura.CuraApplication
 
 from . import Exceptions
 from .CuraContainerStack import CuraContainerStack
 
+if TYPE_CHECKING:
+    from cura.Settings.ExtruderStack import ExtruderStack
+
 ##  Represents the Global or Machine stack and its related containers.
 #
 class GlobalStack(CuraContainerStack):
-    def __init__(self, container_id: str):
+    def __init__(self, container_id: str) -> None:
         super().__init__(container_id)
 
         self.addMetaDataEntry("type", "machine")  # For backward compatibility
@@ -34,7 +35,7 @@ class GlobalStack(CuraContainerStack):
         # and if so, to bypass the resolve to prevent an infinite recursion that would occur
         # if the resolve function tried to access the same property it is a resolve for.
         # Per thread we have our own resolving_settings, or strange things sometimes occur.
-        self._resolving_settings = defaultdict(set)  # keys are thread names
+        self._resolving_settings = defaultdict(set) #type: Dict[str, Set[str]] # keys are thread names
 
     ##  Get the list of extruders of this stack.
     #
@@ -94,6 +95,7 @@ class GlobalStack(CuraContainerStack):
         context.pushContainer(self)
 
         # Handle the "resolve" property.
+        #TODO: Why the hell does this involve threading?
         if self._shouldResolve(key, property_name, context):
             current_thread = threading.current_thread()
             self._resolving_settings[current_thread.name].add(key)
@@ -106,7 +108,7 @@ class GlobalStack(CuraContainerStack):
         limit_to_extruder = super().getProperty(key, "limit_to_extruder", context)
         if limit_to_extruder is not None:
             if limit_to_extruder == -1:
-                limit_to_extruder = int(Application.getInstance().getMachineManager().defaultExtruderPosition)
+                limit_to_extruder = int(cura.CuraApplication.CuraApplication.getInstance().getMachineManager().defaultExtruderPosition)
             limit_to_extruder = str(limit_to_extruder)
         if limit_to_extruder is not None and limit_to_extruder != "-1" and limit_to_extruder in self._extruders:
             if super().getProperty(key, "settable_per_extruder", context):
@@ -155,7 +157,7 @@ class GlobalStack(CuraContainerStack):
 
     ##  Perform some sanity checks on the global stack
     #   Sanity check for extruders; they must have positions 0 and up to machine_extruder_count - 1
-    def isValid(self):
+    def isValid(self) -> bool:
         container_registry = ContainerRegistry.getInstance()
         extruder_trains = container_registry.findContainerStacks(type = "extruder_train", machine = self.getId())
 

cura/Settings/MachineManager.py

@@ -1,10 +1,9 @@
-# Copyright (c) 2017 Ultimaker B.V.
+# Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
 
 import collections
 import time
-#Type hinting.
+from typing import Any, Callable, List, Dict, TYPE_CHECKING, Optional
-from typing import List, Dict, TYPE_CHECKING, Optional
 
 from UM.ConfigurationErrorMessage import ConfigurationErrorMessage
 from UM.Scene.Iterator.DepthFirstIterator import DepthFirstIterator
@@ -15,20 +14,22 @@ from UM.Signal import Signal
 from PyQt5.QtCore import QObject, pyqtProperty, pyqtSignal, QTimer
 from UM.FlameProfiler import pyqtSlot
 from UM import Util
-
-from UM.Application import Application
 from UM.Logger import Logger
 from UM.Message import Message
 
-from UM.Settings.ContainerRegistry import ContainerRegistry
 from UM.Settings.SettingFunction import SettingFunction
 from UM.Signal import postponeSignals, CompressTechnique
 
+import cura.CuraApplication
+from cura.Machines.ContainerNode import ContainerNode #For typing.
+from cura.Machines.QualityChangesGroup import QualityChangesGroup #For typing.
+from cura.Machines.QualityGroup import QualityGroup #For typing.
 from cura.Machines.QualityManager import getMachineDefinitionIDForQualitySearch
 from cura.PrinterOutputDevice import PrinterOutputDevice
 from cura.PrinterOutput.ConfigurationModel import ConfigurationModel
 from cura.PrinterOutput.ExtruderConfigurationModel import ExtruderConfigurationModel
 from cura.PrinterOutput.MaterialOutputModel import MaterialOutputModel
+from cura.Settings.CuraContainerRegistry import CuraContainerRegistry
 from cura.Settings.ExtruderManager import ExtruderManager
 from cura.Settings.ExtruderStack import ExtruderStack
 
@@ -40,29 +41,31 @@ catalog = i18nCatalog("cura")
 if TYPE_CHECKING:
     from cura.Settings.CuraContainerStack import CuraContainerStack
     from cura.Settings.GlobalStack import GlobalStack
+    from cura.Machines.MaterialManager import MaterialManager
+    from cura.Machines.QualityManager import QualityManager
+    from cura.Machines.VariantManager import VariantManager
 
 class MachineManager(QObject):
-
+    def __init__(self, parent: QObject = None) -> None:
-    def __init__(self, parent = None):
         super().__init__(parent)
 
         self._active_container_stack = None     # type: Optional[ExtruderManager]
         self._global_container_stack = None     # type: Optional[GlobalStack]
 
         self._current_root_material_id = {}  # type: Dict[str, str]
-        self._current_quality_group = None
+        self._current_quality_group = None   # type: Optional[QualityGroup]
-        self._current_quality_changes_group = None
+        self._current_quality_changes_group = None  # type: Optional[QualityChangesGroup]
 
         self._default_extruder_position = "0"  # to be updated when extruders are switched on and off
 
-        self.machine_extruder_material_update_dict = collections.defaultdict(list)
+        self.machine_extruder_material_update_dict = collections.defaultdict(list) #type: Dict[str, List[Callable[[], None]]]
 
-        self._instance_container_timer = QTimer()
+        self._instance_container_timer = QTimer() #type: QTimer
         self._instance_container_timer.setInterval(250)
         self._instance_container_timer.setSingleShot(True)
         self._instance_container_timer.timeout.connect(self.__emitChangedSignals)
 
-        self._application = Application.getInstance()
+        self._application = cura.CuraApplication.CuraApplication.getInstance() #type: cura.CuraApplication.CuraApplication
         self._application.globalContainerStackChanged.connect(self._onGlobalContainerChanged)
         self._application.getContainerRegistry().containerLoadComplete.connect(self._onContainersChanged)
 
@@ -74,14 +77,14 @@ class MachineManager(QObject):
         self.globalContainerChanged.connect(self.activeQualityChangesGroupChanged)
         self.globalContainerChanged.connect(self.activeQualityGroupChanged)
 
-        self._stacks_have_errors = None  # type:Optional[bool]
+        self._stacks_have_errors = None  # type: Optional[bool]
 
-        self._empty_container = ContainerRegistry.getInstance().getEmptyInstanceContainer()
+        self._empty_container = CuraContainerRegistry.getInstance().getEmptyInstanceContainer() #type: InstanceContainer
-        self._empty_definition_changes_container = ContainerRegistry.getInstance().findContainers(id = "empty_definition_changes")[0]
+        self._empty_definition_changes_container = CuraContainerRegistry.getInstance().findContainers(id = "empty_definition_changes")[0] #type: InstanceContainer
-        self._empty_variant_container = ContainerRegistry.getInstance().findContainers(id = "empty_variant")[0]
+        self._empty_variant_container = CuraContainerRegistry.getInstance().findContainers(id = "empty_variant")[0] #type: InstanceContainer
-        self._empty_material_container = ContainerRegistry.getInstance().findContainers(id = "empty_material")[0]
+        self._empty_material_container = CuraContainerRegistry.getInstance().findContainers(id = "empty_material")[0] #type: InstanceContainer
-        self._empty_quality_container = ContainerRegistry.getInstance().findContainers(id = "empty_quality")[0]
+        self._empty_quality_container = CuraContainerRegistry.getInstance().findContainers(id = "empty_quality")[0] #type: InstanceContainer
-        self._empty_quality_changes_container = ContainerRegistry.getInstance().findContainers(id = "empty_quality_changes")[0]
+        self._empty_quality_changes_container = CuraContainerRegistry.getInstance().findContainers(id = "empty_quality_changes")[0] #type: InstanceContainer
 
         self._onGlobalContainerChanged()
 
@@ -99,8 +102,6 @@ class MachineManager(QObject):
 
         self._application.getPreferences().addPreference("cura/active_machine", "")
 
-        self._global_event_keys = set()
-
         self._printer_output_devices = []  # type: List[PrinterOutputDevice]
         self._application.getOutputDeviceManager().outputDevicesChanged.connect(self._onOutputDevicesChanged)
         # There might already be some output devices by the time the signal is connected
@@ -116,15 +117,15 @@ class MachineManager(QObject):
 
         self._material_incompatible_message = Message(catalog.i18nc("@info:status",
                                                 "The selected material is incompatible with the selected machine or configuration."),
-                                                title = catalog.i18nc("@info:title", "Incompatible Material"))
+                                                title = catalog.i18nc("@info:title", "Incompatible Material")) #type: Message
 
-        containers = ContainerRegistry.getInstance().findInstanceContainers(id = self.activeMaterialId)
+        containers = CuraContainerRegistry.getInstance().findInstanceContainers(id = self.activeMaterialId) #type: List[InstanceContainer]
         if containers:
             containers[0].nameChanged.connect(self._onMaterialNameChanged)
 
-        self._material_manager = self._application.getMaterialManager()
+        self._material_manager = self._application.getMaterialManager() #type: MaterialManager
-        self._variant_manager = self._application.getVariantManager()
+        self._variant_manager = self._application.getVariantManager() #type: VariantManager
-        self._quality_manager = self._application.getQualityManager()
+        self._quality_manager = self._application.getQualityManager() #type: QualityManager
 
         # When the materials lookup table gets updated, it can mean that a material has its name changed, which should
         # be reflected on the GUI. This signal emission makes sure that it happens.
@@ -164,7 +165,7 @@ class MachineManager(QObject):
 
     def setInitialActiveMachine(self) -> None:
         active_machine_id = self._application.getPreferences().getValue("cura/active_machine")
-        if active_machine_id != "" and ContainerRegistry.getInstance().findContainerStacksMetadata(id = active_machine_id):
+        if active_machine_id != "" and CuraContainerRegistry.getInstance().findContainerStacksMetadata(id = active_machine_id):
             # An active machine was saved, so restore it.
             self.setActiveMachine(active_machine_id)
 
@@ -215,7 +216,7 @@ class MachineManager(QObject):
 
     @pyqtProperty(int, constant=True)
     def totalNumberOfSettings(self) -> int:
-        return len(ContainerRegistry.getInstance().findDefinitionContainers(id = "fdmprinter")[0].getAllKeys())
+        return len(CuraContainerRegistry.getInstance().findDefinitionContainers(id = "fdmprinter")[0].getAllKeys())
 
     def _onGlobalContainerChanged(self) -> None:
         if self._global_container_stack:
@@ -355,7 +356,7 @@ class MachineManager(QObject):
     def setActiveMachine(self, stack_id: str) -> None:
         self.blurSettings.emit()  # Ensure no-one has focus.
 
-        container_registry = ContainerRegistry.getInstance()
+        container_registry = CuraContainerRegistry.getInstance()
 
         containers = container_registry.findContainerStacks(id = stack_id)
         if not containers:
@@ -381,7 +382,7 @@ class MachineManager(QObject):
     #   \param metadata_filter \type{dict} list of metadata keys and values used for filtering
     @staticmethod
     def getMachine(definition_id: str, metadata_filter: Dict[str, str] = None) -> Optional["GlobalStack"]:
-        machines = ContainerRegistry.getInstance().findContainerStacks(type = "machine", **metadata_filter)
+        machines = CuraContainerRegistry.getInstance().findContainerStacks(type = "machine", **metadata_filter)
         for machine in machines:
             if machine.definition.getId() == definition_id:
                 return machine
@@ -625,11 +626,13 @@ class MachineManager(QObject):
     ## Check if a container is read_only
     @pyqtSlot(str, result = bool)
     def isReadOnly(self, container_id: str) -> bool:
-        return ContainerRegistry.getInstance().isReadOnly(container_id)
+        return CuraContainerRegistry.getInstance().isReadOnly(container_id)
 
     ## Copy the value of the setting of the current extruder to all other extruders as well as the global container.
     @pyqtSlot(str)
     def copyValueToExtruders(self, key: str) -> None:
+        if self._active_container_stack is None or self._global_container_stack is None:
+            return
         new_value = self._active_container_stack.getProperty(key, "value")
         extruder_stacks = [stack for stack in ExtruderManager.getInstance().getMachineExtruders(self._global_container_stack.getId())]
 
@@ -641,6 +644,8 @@ class MachineManager(QObject):
     ## Copy the value of all manually changed settings of the current extruder to all other extruders.
     @pyqtSlot()
     def copyAllValuesToExtruders(self) -> None:
+        if self._active_container_stack is None or self._global_container_stack is None:
+            return
         extruder_stacks = list(self._global_container_stack.extruders.values())
         for extruder_stack in extruder_stacks:
             if extruder_stack != self._active_container_stack:
@@ -704,7 +709,7 @@ class MachineManager(QObject):
 
     @pyqtSlot(str, str)
     def renameMachine(self, machine_id: str, new_name: str) -> None:
-        container_registry = ContainerRegistry.getInstance()
+        container_registry = CuraContainerRegistry.getInstance()
         machine_stack = container_registry.findContainerStacks(id = machine_id)
         if machine_stack:
             new_name = container_registry.createUniqueName("machine", machine_stack[0].getName(), new_name, machine_stack[0].definition.getName())
@@ -718,23 +723,23 @@ class MachineManager(QObject):
 
         # activate a new machine before removing a machine because this is safer
         if activate_new_machine:
-            machine_stacks = ContainerRegistry.getInstance().findContainerStacksMetadata(type = "machine")
+            machine_stacks = CuraContainerRegistry.getInstance().findContainerStacksMetadata(type = "machine")
             other_machine_stacks = [s for s in machine_stacks if s["id"] != machine_id]
             if other_machine_stacks:
                 self.setActiveMachine(other_machine_stacks[0]["id"])
 
-        metadata = ContainerRegistry.getInstance().findContainerStacksMetadata(id = machine_id)[0]
+        metadata = CuraContainerRegistry.getInstance().findContainerStacksMetadata(id = machine_id)[0]
         network_key = metadata["um_network_key"] if "um_network_key" in metadata else None
         ExtruderManager.getInstance().removeMachineExtruders(machine_id)
-        containers = ContainerRegistry.getInstance().findInstanceContainersMetadata(type = "user", machine = machine_id)
+        containers = CuraContainerRegistry.getInstance().findInstanceContainersMetadata(type = "user", machine = machine_id)
         for container in containers:
-            ContainerRegistry.getInstance().removeContainer(container["id"])
+            CuraContainerRegistry.getInstance().removeContainer(container["id"])
-        ContainerRegistry.getInstance().removeContainer(machine_id)
+        CuraContainerRegistry.getInstance().removeContainer(machine_id)
 
         # If the printer that is being removed is a network printer, the hidden printers have to be also removed
         if network_key:
             metadata_filter = {"um_network_key": network_key}
-            hidden_containers = ContainerRegistry.getInstance().findContainerStacks(type = "machine", **metadata_filter)
+            hidden_containers = CuraContainerRegistry.getInstance().findContainerStacks(type = "machine", **metadata_filter)
             if hidden_containers:
                 # This reuses the method and remove all printers recursively
                 self.removeMachine(hidden_containers[0].getId())
@@ -802,14 +807,17 @@ class MachineManager(QObject):
 
     ##  Get the Definition ID of a machine (specified by ID)
     #   \param machine_id string machine id to get the definition ID of
-    #   \returns DefinitionID (string) if found, None otherwise
+    #   \returns DefinitionID if found, None otherwise
     @pyqtSlot(str, result = str)
-    def getDefinitionByMachineId(self, machine_id: str) -> str:
+    def getDefinitionByMachineId(self, machine_id: str) -> Optional[str]:
-        containers = ContainerRegistry.getInstance().findContainerStacks(id = machine_id)
+        containers = CuraContainerRegistry.getInstance().findContainerStacks(id = machine_id)
         if containers:
             return containers[0].definition.getId()
+        return None
 
     def getIncompatibleSettingsOnEnabledExtruders(self, container: InstanceContainer) -> List[str]:
+        if self._global_container_stack is None:
+            return []
         extruder_count = self._global_container_stack.getProperty("machine_extruder_count", "value")
         result = []  # type: List[str]
         for setting_instance in container.findInstances():
@@ -834,6 +842,8 @@ class MachineManager(QObject):
 
     ##  Update extruder number to a valid value when the number of extruders are changed, or when an extruder is changed
     def correctExtruderSettings(self) -> None:
+        if self._global_container_stack is None:
+            return
         for setting_key in self.getIncompatibleSettingsOnEnabledExtruders(self._global_container_stack.userChanges):
             self._global_container_stack.userChanges.removeInstance(setting_key)
         add_user_changes = self.getIncompatibleSettingsOnEnabledExtruders(self._global_container_stack.qualityChanges)
@@ -851,6 +861,8 @@ class MachineManager(QObject):
     ##  Set the amount of extruders on the active machine (global stack)
     #   \param extruder_count int the number of extruders to set
     def setActiveMachineExtruderCount(self, extruder_count: int) -> None:
+        if self._global_container_stack is None:
+            return
         extruder_manager = self._application.getExtruderManager()
 
         definition_changes_container = self._global_container_stack.definitionChanges
@@ -869,7 +881,7 @@ class MachineManager(QObject):
 
         # Check to see if any objects are set to print with an extruder that will no longer exist
         root_node = self._application.getController().getScene().getRoot()
-        for node in DepthFirstIterator(root_node):
+        for node in DepthFirstIterator(root_node): #type: ignore #Ignore type error because iter() should get called automatically by Python syntax.
             if node.getMeshData():
                 extruder_nr = node.callDecoration("getActiveExtruderPosition")
 
@@ -884,7 +896,7 @@ class MachineManager(QObject):
         global_user_container = self._global_container_stack.userChanges
 
         # Make sure extruder_stacks exists
-        extruder_stacks = []
+        extruder_stacks = [] #type: List[ExtruderStack]
 
         if previous_extruder_count == 1:
             extruder_stacks = ExtruderManager.getInstance().getActiveExtruderStacks()
@@ -912,6 +924,8 @@ class MachineManager(QObject):
         return extruder
 
     def updateDefaultExtruder(self) -> None:
+        if self._global_container_stack is None:
+            return
         extruder_items = sorted(self._global_container_stack.extruders.items())
         old_position = self._default_extruder_position
         new_default_position = "0"
@@ -924,6 +938,8 @@ class MachineManager(QObject):
             self.extruderChanged.emit()
 
     def updateNumberExtrudersEnabled(self) -> None:
+        if self._global_container_stack is None:
+            return
         definition_changes_container = self._global_container_stack.definitionChanges
         machine_extruder_count = self._global_container_stack.getProperty("machine_extruder_count", "value")
         extruder_count = 0
@@ -936,6 +952,8 @@ class MachineManager(QObject):
 
     @pyqtProperty(int, notify = numberExtrudersEnabledChanged)
     def numberExtrudersEnabled(self) -> int:
+        if self._global_container_stack is None:
+            return 1
         return self._global_container_stack.definitionChanges.getProperty("extruders_enabled_count", "value")
 
     @pyqtProperty(str, notify = extruderChanged)
@@ -945,6 +963,8 @@ class MachineManager(QObject):
     ##  This will fire the propertiesChanged for all settings so they will be updated in the front-end
     @pyqtSlot()
     def forceUpdateAllSettings(self) -> None:
+        if self._global_container_stack is None:
+            return
         with postponeSignals(*self._getContainerChangedSignals(), compress = CompressTechnique.CompressPerParameterValue):
             property_names = ["value", "resolve", "validationState"]
             for container in [self._global_container_stack] + list(self._global_container_stack.extruders.values()):
@@ -954,8 +974,9 @@ class MachineManager(QObject):
     @pyqtSlot(int, bool)
     def setExtruderEnabled(self, position: int, enabled: bool) -> None:
         extruder = self.getExtruder(position)
-        if not extruder:
+        if not extruder or self._global_container_stack is None:
             Logger.log("w", "Could not find extruder on position %s", position)
+            return
 
         extruder.setEnabled(enabled)
         self.updateDefaultExtruder()
@@ -991,6 +1012,8 @@ class MachineManager(QObject):
 
     @pyqtSlot(str, str, str)
     def setSettingForAllExtruders(self, setting_name: str, property_name: str, property_value: str) -> None:
+        if self._global_container_stack is None:
+            return
         for key, extruder in self._global_container_stack.extruders.items():
             container = extruder.userChanges
             container.setProperty(setting_name, property_name, property_value)
@@ -999,6 +1022,8 @@ class MachineManager(QObject):
     #   \param setting_name The ID of the setting to reset.
     @pyqtSlot(str)
     def resetSettingForAllExtruders(self, setting_name: str) -> None:
+        if self._global_container_stack is None:
+            return
         for key, extruder in self._global_container_stack.extruders.items():
             container = extruder.userChanges
             container.removeInstance(setting_name)
@@ -1041,6 +1066,8 @@ class MachineManager(QObject):
     # for all stacks in the currently active machine.
     #
     def _setEmptyQuality(self) -> None:
+        if self._global_container_stack is None:
+            return
         self._current_quality_group = None
         self._current_quality_changes_group = None
         self._global_container_stack.quality = self._empty_quality_container
@@ -1052,12 +1079,14 @@ class MachineManager(QObject):
         self.activeQualityGroupChanged.emit()
         self.activeQualityChangesGroupChanged.emit()
 
-    def _setQualityGroup(self, quality_group, empty_quality_changes: bool = True) -> None:
+    def _setQualityGroup(self, quality_group: Optional[QualityGroup], empty_quality_changes: bool = True) -> None:
+        if self._global_container_stack is None:
+            return
         if quality_group is None:
             self._setEmptyQuality()
             return
 
-        if quality_group.node_for_global.getContainer() is None:
+        if quality_group.node_for_global is None or quality_group.node_for_global.getContainer() is None:
             return
         for node in quality_group.nodes_for_extruders.values():
             if node.getContainer() is None:
@@ -1081,14 +1110,15 @@ class MachineManager(QObject):
         self.activeQualityGroupChanged.emit()
         self.activeQualityChangesGroupChanged.emit()
 
-    def _fixQualityChangesGroupToNotSupported(self, quality_changes_group):
+    def _fixQualityChangesGroupToNotSupported(self, quality_changes_group: QualityChangesGroup) -> None:
         nodes = [quality_changes_group.node_for_global] + list(quality_changes_group.nodes_for_extruders.values())
         containers = [n.getContainer() for n in nodes if n is not None]
         for container in containers:
-            container.setMetaDataEntry("quality_type", "not_supported")
+            if container:
+                container.setMetaDataEntry("quality_type", "not_supported")
         quality_changes_group.quality_type = "not_supported"
 
-    def _setQualityChangesGroup(self, quality_changes_group):
+    def _setQualityChangesGroup(self, quality_changes_group: QualityChangesGroup) -> None:
         if self._global_container_stack is None:
             return #Can't change that.
         quality_type = quality_changes_group.quality_type
@@ -1132,21 +1162,25 @@ class MachineManager(QObject):
         self.activeQualityGroupChanged.emit()
         self.activeQualityChangesGroupChanged.emit()
 
-    def _setVariantNode(self, position, container_node):
+    def _setVariantNode(self, position: str, container_node: ContainerNode) -> None:
-        if container_node.getContainer() is None:
+        if container_node.getContainer() is None or self._global_container_stack is None:
             return
         self._global_container_stack.extruders[position].variant = container_node.getContainer()
         self.activeVariantChanged.emit()
 
-    def _setGlobalVariant(self, container_node):
+    def _setGlobalVariant(self, container_node: ContainerNode) -> None:
+        if self._global_container_stack is None:
+            return
         self._global_container_stack.variant = container_node.getContainer()
         if not self._global_container_stack.variant:
             self._global_container_stack.variant = self._application.empty_variant_container
 
-    def _setMaterial(self, position, container_node = None):
+    def _setMaterial(self, position: str, container_node: ContainerNode = None) -> None:
+        if self._global_container_stack is None:
+            return
         if container_node and container_node.getContainer():
             self._global_container_stack.extruders[position].material = container_node.getContainer()
-            root_material_id = container_node.metadata["base_file"]
+            root_material_id = container_node.getMetaDataEntry("base_file", None)
         else:
             self._global_container_stack.extruders[position].material = self._empty_material_container
             root_material_id = None
@@ -1155,18 +1189,19 @@ class MachineManager(QObject):
             self._current_root_material_id[position] = root_material_id
             self.rootMaterialChanged.emit()
 
-    def activeMaterialsCompatible(self):
+    def activeMaterialsCompatible(self) -> bool:
         # check material - variant compatibility
-        if Util.parseBool(self._global_container_stack.getMetaDataEntry("has_materials", False)):
+        if self._global_container_stack is not None:
-            for position, extruder in self._global_container_stack.extruders.items():
+            if Util.parseBool(self._global_container_stack.getMetaDataEntry("has_materials", False)):
-                if extruder.isEnabled and not extruder.material.getMetaDataEntry("compatible"):
+                for position, extruder in self._global_container_stack.extruders.items():
-                    return False
+                    if extruder.isEnabled and not extruder.material.getMetaDataEntry("compatible"):
-                if not extruder.material.getMetaDataEntry("compatible"):
+                        return False
-                    return False
+                    if not extruder.material.getMetaDataEntry("compatible"):
+                        return False
         return True
 
     ## Update current quality type and machine after setting material
-    def _updateQualityWithMaterial(self, *args):
+    def _updateQualityWithMaterial(self, *args: Any) -> None:
         if self._global_container_stack is None:
             return
         Logger.log("i", "Updating quality/quality_changes due to material change")
@@ -1205,7 +1240,7 @@ class MachineManager(QObject):
                    current_quality_type, quality_type)
         self._setQualityGroup(candidate_quality_groups[quality_type], empty_quality_changes = True)
 
-    def updateMaterialWithVariant(self, position: Optional[str]):
+    def updateMaterialWithVariant(self, position: Optional[str]) -> None:
         if self._global_container_stack is None:
             return
         if position is None:
@@ -1213,8 +1248,8 @@ class MachineManager(QObject):
         else:
             position_list = [position]
 
-        for position in position_list:
+        for position_item in position_list:
-            extruder = self._global_container_stack.extruders[position]
+            extruder = self._global_container_stack.extruders[position_item]
 
             current_material_base_name = extruder.material.getMetaDataEntry("base_file")
             current_variant_name = None
@@ -1232,28 +1267,28 @@ class MachineManager(QObject):
                 material_diameter)
 
             if not candidate_materials:
-                self._setMaterial(position, container_node = None)
+                self._setMaterial(position_item, container_node = None)
                 continue
 
             if current_material_base_name in candidate_materials:
                 new_material = candidate_materials[current_material_base_name]
-                self._setMaterial(position, new_material)
+                self._setMaterial(position_item, new_material)
                 continue
 
             # The current material is not available, find the preferred one
             material_node = self._material_manager.getDefaultMaterial(self._global_container_stack, current_variant_name)
             if material_node is not None:
-                self._setMaterial(position, material_node)
+                self._setMaterial(position_item, material_node)
 
     ##  Given a printer definition name, select the right machine instance. In case it doesn't exist, create a new
     #   instance with the same network key.
     @pyqtSlot(str)
     def switchPrinterType(self, machine_name: str) -> None:
         # Don't switch if the user tries to change to the same type of printer
-        if self.activeMachineDefinitionName == machine_name:
+        if self._global_container_stack is None or self.self.activeMachineDefinitionName == machine_name:
             return
         # Get the definition id corresponding to this machine name
-        machine_definition_id = ContainerRegistry.getInstance().findDefinitionContainers(name = machine_name)[0].getId()
+        machine_definition_id = CuraContainerRegistry.getInstance().findDefinitionContainers(name = machine_name)[0].getId()
         # Try to find a machine with the same network key
         new_machine = self.getMachine(machine_definition_id, metadata_filter = {"um_network_key": self.activeMachineNetworkKey})
         # If there is no machine, then create a new one and set it to the non-hidden instance
@@ -1275,6 +1310,8 @@ class MachineManager(QObject):
 
     @pyqtSlot(QObject)
     def applyRemoteConfiguration(self, configuration: ConfigurationModel) -> None:
+        if self._global_container_stack is None:
+            return
         self.blurSettings.emit()
         with postponeSignals(*self._getContainerChangedSignals(), compress = CompressTechnique.CompressPerParameterValue):
             self.switchPrinterType(configuration.printerType)
@@ -1309,7 +1346,7 @@ class MachineManager(QObject):
 
     ##  Find all container stacks that has the pair 'key = value' in its metadata and replaces the value with 'new_value'
     def replaceContainersMetadata(self, key: str, value: str, new_value: str) -> None:
-        machines = ContainerRegistry.getInstance().findContainerStacks(type = "machine")
+        machines = CuraContainerRegistry.getInstance().findContainerStacks(type = "machine")
         for machine in machines:
             if machine.getMetaDataEntry(key) == value:
                 machine.setMetaDataEntry(key, new_value)
@@ -1322,18 +1359,18 @@ class MachineManager(QObject):
             # Check if the connect_group_name is correct. If not, update all the containers connected to the same printer
             if self.activeMachineNetworkGroupName != group_name:
                 metadata_filter = {"um_network_key": self.activeMachineNetworkKey}
-                containers = ContainerRegistry.getInstance().findContainerStacks(type = "machine", **metadata_filter)
+                containers = CuraContainerRegistry.getInstance().findContainerStacks(type = "machine", **metadata_filter)
                 for container in containers:
                     container.setMetaDataEntry("connect_group_name", group_name)
 
     ##  This method checks if there is an instance connected to the given network_key
     def existNetworkInstances(self, network_key: str) -> bool:
         metadata_filter = {"um_network_key": network_key}
-        containers = ContainerRegistry.getInstance().findContainerStacks(type = "machine", **metadata_filter)
+        containers = CuraContainerRegistry.getInstance().findContainerStacks(type = "machine", **metadata_filter)
         return bool(containers)
 
     @pyqtSlot("QVariant")
-    def setGlobalVariant(self, container_node):
+    def setGlobalVariant(self, container_node: ContainerNode) -> None:
         self.blurSettings.emit()
         with postponeSignals(*self._getContainerChangedSignals(), compress = CompressTechnique.CompressPerParameterValue):
             self._setGlobalVariant(container_node)
@@ -1341,7 +1378,9 @@ class MachineManager(QObject):
             self._updateQualityWithMaterial()
 
     @pyqtSlot(str, str)
-    def setMaterialById(self, position, root_material_id):
+    def setMaterialById(self, position: str, root_material_id: str) -> None:
+        if self._global_container_stack is None:
+            return
         machine_definition_id = self._global_container_stack.definition.id
         position = str(position)
         extruder_stack = self._global_container_stack.extruders[position]
@@ -1364,12 +1403,14 @@ class MachineManager(QObject):
 
     @pyqtSlot(str, str)
     def setVariantByName(self, position: str, variant_name: str) -> None:
+        if self._global_container_stack is None:
+            return
         machine_definition_id = self._global_container_stack.definition.id
         variant_node = self._variant_manager.getVariantNode(machine_definition_id, variant_name)
         self.setVariant(position, variant_node)
 
     @pyqtSlot(str, "QVariant")
-    def setVariant(self, position: str, container_node):
+    def setVariant(self, position: str, container_node: ContainerNode) -> None:
         position = str(position)
         self.blurSettings.emit()
         with postponeSignals(*self._getContainerChangedSignals(), compress = CompressTechnique.CompressPerParameterValue):
@@ -1391,7 +1432,7 @@ class MachineManager(QObject):
         self.setQualityGroup(quality_group)
 
     @pyqtSlot(QObject)
-    def setQualityGroup(self, quality_group, no_dialog = False):
+    def setQualityGroup(self, quality_group: QualityGroup, no_dialog: bool = False) -> None:
         self.blurSettings.emit()
         with postponeSignals(*self._getContainerChangedSignals(), compress = CompressTechnique.CompressPerParameterValue):
             self._setQualityGroup(quality_group)
@@ -1401,11 +1442,11 @@ class MachineManager(QObject):
             self._application.discardOrKeepProfileChanges()
 
     @pyqtProperty(QObject, fset = setQualityGroup, notify = activeQualityGroupChanged)
-    def activeQualityGroup(self):
+    def activeQualityGroup(self) -> Optional[QualityGroup]:
         return self._current_quality_group
 
     @pyqtSlot(QObject)
-    def setQualityChangesGroup(self, quality_changes_group, no_dialog = False):
+    def setQualityChangesGroup(self, quality_changes_group: QualityChangesGroup, no_dialog: bool = False) -> None:
         self.blurSettings.emit()
         with postponeSignals(*self._getContainerChangedSignals(), compress = CompressTechnique.CompressPerParameterValue):
             self._setQualityChangesGroup(quality_changes_group)
@@ -1415,18 +1456,20 @@ class MachineManager(QObject):
             self._application.discardOrKeepProfileChanges()
 
     @pyqtSlot()
-    def resetToUseDefaultQuality(self):
+    def resetToUseDefaultQuality(self) -> None:
+        if self._global_container_stack is None:
+            return
         with postponeSignals(*self._getContainerChangedSignals(), compress = CompressTechnique.CompressPerParameterValue):
             self._setQualityGroup(self._current_quality_group)
             for stack in [self._global_container_stack] + list(self._global_container_stack.extruders.values()):
                 stack.userChanges.clear()
 
     @pyqtProperty(QObject, fset = setQualityChangesGroup, notify = activeQualityChangesGroupChanged)
-    def activeQualityChangesGroup(self):
+    def activeQualityChangesGroup(self) -> Optional[QualityChangesGroup]:
         return self._current_quality_changes_group
 
     @pyqtProperty(str, notify = activeQualityGroupChanged)
-    def activeQualityOrQualityChangesName(self):
+    def activeQualityOrQualityChangesName(self) -> str:
         name = self._empty_quality_container.getName()
         if self._current_quality_changes_group:
             name = self._current_quality_changes_group.name

cura/Settings/PerObjectContainerStack.py

@@ -1,3 +1,6 @@
+# Copyright (c) 2018 Ultimaker B.V.
+# Cura is released under the terms of the LGPLv3 or higher.
+
 from typing import Any, Optional
 
 from UM.Application import Application
@@ -9,7 +12,6 @@ from .CuraContainerStack import CuraContainerStack
 
 
 class PerObjectContainerStack(CuraContainerStack):
-
     @override(CuraContainerStack)
     def getProperty(self, key: str, property_name: str, context: Optional[PropertyEvaluationContext] = None) -> Any:
         if context is None:
@@ -20,7 +22,7 @@ class PerObjectContainerStack(CuraContainerStack):
 
         # Return the user defined value if present, otherwise, evaluate the value according to the default routine.
         if self.getContainer(0).hasProperty(key, property_name):
-            if self.getContainer(0)._instances[key].state == InstanceState.User:
+            if self.getContainer(0).getProperty(key, "state") == InstanceState.User:
                 result = super().getProperty(key, property_name, context)
                 context.popContainer()
                 return result
@@ -53,13 +55,13 @@ class PerObjectContainerStack(CuraContainerStack):
         return result
 
     @override(CuraContainerStack)
-    def setNextStack(self, stack: CuraContainerStack):
+    def setNextStack(self, stack: CuraContainerStack) -> None:
         super().setNextStack(stack)
 
         # trigger signal to re-evaluate all default settings
-        for key, instance in self.getContainer(0)._instances.items():
+        for key in self.getContainer(0).getAllKeys():
             # only evaluate default settings
-            if instance.state != InstanceState.Default:
+            if self.getContainer(0).getProperty(key, "state") != InstanceState.Default:
                 continue
 
             self._collectPropertyChanges(key, "value")

cura/Settings/SettingInheritanceManager.py

@@ -1,5 +1,6 @@
 # Copyright (c) 2017 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
+from typing import List
 
 from PyQt5.QtCore import QObject, QTimer, pyqtProperty, pyqtSignal
 from UM.FlameProfiler import pyqtSlot
@@ -13,6 +14,7 @@ from UM.Logger import Logger
 #     speed settings. If all the children of print_speed have a single value override, changing the speed won't
 #     actually do anything, as only the 'leaf' settings are used by the engine.
 from UM.Settings.ContainerStack import ContainerStack
+from UM.Settings.Interfaces import ContainerInterface
 from UM.Settings.SettingFunction import SettingFunction
 from UM.Settings.SettingInstance import InstanceState
 
@@ -157,7 +159,7 @@ class SettingInheritanceManager(QObject):
             stack = self._active_container_stack
         if not stack: #No active container stack yet!
             return False
-        containers = []
+        containers = [] # type: List[ContainerInterface]
 
         ## Check if the setting has a user state. If not, it is never overwritten.
         has_user_state = stack.getProperty(key, "state") == InstanceState.User

cura/Settings/SimpleModeSettingsManager.py

@@ -39,12 +39,12 @@ class SimpleModeSettingsManager(QObject):
         global_stack = self._machine_manager.activeMachine
 
         # check user settings in the global stack
-        user_setting_keys.update(set(global_stack.userChanges.getAllKeys()))
+        user_setting_keys.update(global_stack.userChanges.getAllKeys())
 
         # check user settings in the extruder stacks
         if global_stack.extruders:
             for extruder_stack in global_stack.extruders.values():
-                user_setting_keys.update(set(extruder_stack.userChanges.getAllKeys()))
+                user_setting_keys.update(extruder_stack.userChanges.getAllKeys())
 
         # remove settings that are visible in recommended (we don't show the reset button for those)
         for skip_key in self.__ignored_custom_setting_keys:
@@ -70,12 +70,12 @@ class SimpleModeSettingsManager(QObject):
         global_stack = self._machine_manager.activeMachine
 
         # check quality changes settings in the global stack
-        quality_changes_keys.update(set(global_stack.qualityChanges.getAllKeys()))
+        quality_changes_keys.update(global_stack.qualityChanges.getAllKeys())
 
         # check quality changes settings in the extruder stacks
         if global_stack.extruders:
             for extruder_stack in global_stack.extruders.values():
-                quality_changes_keys.update(set(extruder_stack.qualityChanges.getAllKeys()))
+                quality_changes_keys.update(extruder_stack.qualityChanges.getAllKeys())
 
         # check if the qualityChanges container is not empty (meaning it is a user created profile)
         has_quality_changes = len(quality_changes_keys) > 0

cura/SingleInstance.py

@@ -7,12 +7,12 @@ from typing import List, Optional
 
 from PyQt5.QtNetwork import QLocalServer, QLocalSocket
 
+from UM.Qt.QtApplication import QtApplication #For typing.
 from UM.Logger import Logger
 
 
 class SingleInstance:
-
+    def __init__(self, application: QtApplication, files_to_open: Optional[List[str]]) -> None:
-    def __init__(self, application, files_to_open: Optional[List[str]]):
         self._application = application
         self._files_to_open = files_to_open
 
@@ -61,17 +61,22 @@ class SingleInstance:
 
     def startServer(self) -> None:
         self._single_instance_server = QLocalServer()
-        self._single_instance_server.newConnection.connect(self._onClientConnected)
+        if self._single_instance_server:
-        self._single_instance_server.listen("ultimaker-cura")
+            self._single_instance_server.newConnection.connect(self._onClientConnected)
+            self._single_instance_server.listen("ultimaker-cura")
+        else:
+            Logger.log("e", "Single instance server was not created.")
 
-    def _onClientConnected(self):
+    def _onClientConnected(self) -> None:
         Logger.log("i", "New connection recevied on our single-instance server")
-        connection = self._single_instance_server.nextPendingConnection()
+        connection = None #type: Optional[QLocalSocket]
+        if self._single_instance_server:
+            connection = self._single_instance_server.nextPendingConnection()
 
         if connection is not None:
             connection.readyRead.connect(lambda c = connection: self.__readCommands(c))
 
-    def __readCommands(self, connection):
+    def __readCommands(self, connection: QLocalSocket) -> None:
         line = connection.readLine()
         while len(line) != 0:    # There is also a .canReadLine()
             try:

plugins/3MFReader/ThreeMFWorkspaceReader.py

@@ -4,7 +4,7 @@
 from configparser import ConfigParser
 import zipfile
 import os
-from typing import List, Tuple
+from typing import Dict, List, Tuple
 
 
 import xml.etree.ElementTree as ET
@@ -38,7 +38,7 @@ i18n_catalog = i18nCatalog("cura")
 
 
 class ContainerInfo:
-    def __init__(self, file_name: str, serialized: str, parser: ConfigParser):
+    def __init__(self, file_name: str, serialized: str, parser: ConfigParser) -> None:
         self.file_name = file_name
         self.serialized = serialized
         self.parser = parser
@@ -47,14 +47,14 @@ class ContainerInfo:
 
 
 class QualityChangesInfo:
-    def __init__(self):
+    def __init__(self) -> None:
         self.name = None
         self.global_info = None
-        self.extruder_info_dict = {}
+        self.extruder_info_dict = {} # type: Dict[str, ContainerInfo]
 
 
 class MachineInfo:
-    def __init__(self):
+    def __init__(self) -> None:
         self.container_id = None
         self.name = None
         self.definition_id = None
@@ -66,11 +66,11 @@ class MachineInfo:
         self.definition_changes_info = None
         self.user_changes_info = None
 
-        self.extruder_info_dict = {}
+        self.extruder_info_dict = {} # type: Dict[str, ExtruderInfo]
 
 
 class ExtruderInfo:
-    def __init__(self):
+    def __init__(self) -> None:
         self.position = None
         self.enabled = True
         self.variant_info = None
@@ -82,7 +82,7 @@ class ExtruderInfo:
 
 ##    Base implementation for reading 3MF workspace files.
 class ThreeMFWorkspaceReader(WorkspaceReader):
-    def __init__(self):
+    def __init__(self) -> None:
         super().__init__()
 
         MimeTypeDatabase.addMimeType(
@@ -112,28 +112,26 @@ class ThreeMFWorkspaceReader(WorkspaceReader):
         #  - variant
         self._ignored_instance_container_types = {"quality", "variant"}
 
-        self._resolve_strategies = {}
+        self._resolve_strategies = {} # type: Dict[str, str]
 
-        self._id_mapping = {}
+        self._id_mapping = {} # type: Dict[str, str]
 
         # In Cura 2.5 and 2.6, the empty profiles used to have those long names
         self._old_empty_profile_id_dict = {"empty_%s" % k: "empty" for k in ["material", "variant"]}
 
         self._is_same_machine_type = False
-        self._old_new_materials = {}
+        self._old_new_materials = {} # type: Dict[str, str]
-        self._materials_to_select = {}
         self._machine_info = None
 
     def _clearState(self):
         self._is_same_machine_type = False
         self._id_mapping = {}
         self._old_new_materials = {}
-        self._materials_to_select = {}
         self._machine_info = None
 
     ##  Get a unique name based on the old_id. This is different from directly calling the registry in that it caches results.
     #   This has nothing to do with speed, but with getting consistent new naming for instances & objects.
-    def getNewId(self, old_id):
+    def getNewId(self, old_id: str):
         if old_id not in self._id_mapping:
             self._id_mapping[old_id] = self._container_registry.uniqueName(old_id)
         return self._id_mapping[old_id]
@@ -671,7 +669,7 @@ class ThreeMFWorkspaceReader(WorkspaceReader):
                 else:
                     material_container = materials[0]
                     old_material_root_id = material_container.getMetaDataEntry("base_file")
-                    if not self._container_registry.isReadOnly(old_material_root_id):  # Only create new materials if they are not read only.
+                    if old_material_root_id is not None and not self._container_registry.isReadOnly(old_material_root_id):  # Only create new materials if they are not read only.
                         to_deserialize_material = True
 
                         if self._resolve_strategies["material"] == "override":

plugins/3MFWriter/ThreeMFWriter.py

@@ -91,7 +91,7 @@ class ThreeMFWriter(MeshWriter):
         # Handle per object settings (if any)
         stack = um_node.callDecoration("getStack")
         if stack is not None:
-            changed_setting_keys = set(stack.getTop().getAllKeys())
+            changed_setting_keys = stack.getTop().getAllKeys()
 
             # Ensure that we save the extruder used for this object in a multi-extrusion setup
             if stack.getProperty("machine_extruder_count", "value") > 1:

plugins/CuraEngineBackend/CuraEngineBackend.py

@@ -1,8 +1,14 @@
-# Copyright (c) 2017 Ultimaker B.V.
+# Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
 
+from collections import defaultdict
+import os
+from PyQt5.QtCore import QObject, QTimer, pyqtSlot
+import sys
+from time import time
+from typing import Any, cast, Dict, List, Optional, Set, TYPE_CHECKING
+
 from UM.Backend.Backend import Backend, BackendState
-from UM.Application import Application
 from UM.Scene.SceneNode import SceneNode
 from UM.Signal import Signal
 from UM.Logger import Logger
@@ -10,29 +16,30 @@ from UM.Message import Message
 from UM.PluginRegistry import PluginRegistry
 from UM.Resources import Resources
 from UM.Platform import Platform
-from UM.Scene.Iterator.DepthFirstIterator import DepthFirstIterator
 from UM.Qt.Duration import DurationFormat
-from PyQt5.QtCore import QObject, pyqtSlot
+from UM.Scene.Iterator.DepthFirstIterator import DepthFirstIterator
+from UM.Settings.Interfaces import DefinitionContainerInterface
+from UM.Settings.SettingInstance import SettingInstance #For typing.
+from UM.Tool import Tool #For typing.
 
-from collections import defaultdict
+from cura.CuraApplication import CuraApplication
 from cura.Settings.ExtruderManager import ExtruderManager
-from . import ProcessSlicedLayersJob
+from .ProcessSlicedLayersJob import ProcessSlicedLayersJob
-from . import StartSliceJob
+from .StartSliceJob import StartSliceJob, StartJobResult
-
-import os
-import sys
-from time import time
-
-from PyQt5.QtCore import QTimer
 
 import Arcus
 
+if TYPE_CHECKING:
+    from cura.Machines.Models.MultiBuildPlateModel import MultiBuildPlateModel
+    from cura.Machines.MachineErrorChecker import MachineErrorChecker
+    from UM.Scene.Scene import Scene
+    from UM.Settings.ContainerStack import ContainerStack
+
 from UM.i18n import i18nCatalog
 catalog = i18nCatalog("cura")
 
 
 class CuraEngineBackend(QObject, Backend):
-
     backendError = Signal()
 
     ##  Starts the back-end plug-in.
@@ -40,16 +47,16 @@ class CuraEngineBackend(QObject, Backend):
     #   This registers all the signal listeners and prepares for communication
     #   with the back-end in general.
     #   CuraEngineBackend is exposed to qml as well.
-    def __init__(self, parent = None):
+    def __init__(self) -> None:
-        super().__init__(parent = parent)
+        super().__init__()
         # Find out where the engine is located, and how it is called.
         # This depends on how Cura is packaged and which OS we are running on.
         executable_name = "CuraEngine"
         if Platform.isWindows():
             executable_name += ".exe"
         default_engine_location = executable_name
-        if os.path.exists(os.path.join(Application.getInstallPrefix(), "bin", executable_name)):
+        if os.path.exists(os.path.join(CuraApplication.getInstallPrefix(), "bin", executable_name)):
-            default_engine_location = os.path.join(Application.getInstallPrefix(), "bin", executable_name)
+            default_engine_location = os.path.join(CuraApplication.getInstallPrefix(), "bin", executable_name)
         if hasattr(sys, "frozen"):
             default_engine_location = os.path.join(os.path.dirname(os.path.abspath(sys.executable)), executable_name)
         if Platform.isLinux() and not default_engine_location:
@@ -61,9 +68,9 @@ class CuraEngineBackend(QObject, Backend):
                     default_engine_location = execpath
                     break
 
-        self._application = Application.getInstance()
+        self._application = CuraApplication.getInstance() #type: CuraApplication
-        self._multi_build_plate_model = None
+        self._multi_build_plate_model = None #type: MultiBuildPlateModel
-        self._machine_error_checker = None
+        self._machine_error_checker = None #type: MachineErrorChecker
 
         if not default_engine_location:
             raise EnvironmentError("Could not find CuraEngine")
@@ -71,16 +78,16 @@ class CuraEngineBackend(QObject, Backend):
         Logger.log("i", "Found CuraEngine at: %s", default_engine_location)
 
         default_engine_location = os.path.abspath(default_engine_location)
-        Application.getInstance().getPreferences().addPreference("backend/location", default_engine_location)
+        self._application.getPreferences().addPreference("backend/location", default_engine_location)
 
         # Workaround to disable layer view processing if layer view is not active.
-        self._layer_view_active = False
+        self._layer_view_active = False #type: bool
         self._onActiveViewChanged()
 
-        self._stored_layer_data = []
+        self._stored_layer_data = [] #type: List[Arcus.PythonMessage]
-        self._stored_optimized_layer_data = {}  # key is build plate number, then arrays are stored until they go to the ProcessSlicesLayersJob
+        self._stored_optimized_layer_data = {} #type: Dict[int, List[Arcus.PythonMessage]] # key is build plate number, then arrays are stored until they go to the ProcessSlicesLayersJob
 
-        self._scene = self._application.getController().getScene()
+        self._scene = self._application.getController().getScene() #type: Scene
         self._scene.sceneChanged.connect(self._onSceneChanged)
 
         # Triggers for auto-slicing. Auto-slicing is triggered as follows:
@@ -91,7 +98,7 @@ class CuraEngineBackend(QObject, Backend):
         # If there is an error check, stop the auto-slicing timer, and only wait for the error check to be finished
         # to start the auto-slicing timer again.
         #
-        self._global_container_stack = None
+        self._global_container_stack = None #type: Optional[ContainerStack]
 
         # Listeners for receiving messages from the back-end.
         self._message_handlers["cura.proto.Layer"] = self._onLayerMessage
@@ -102,39 +109,39 @@ class CuraEngineBackend(QObject, Backend):
         self._message_handlers["cura.proto.PrintTimeMaterialEstimates"] = self._onPrintTimeMaterialEstimates
         self._message_handlers["cura.proto.SlicingFinished"] = self._onSlicingFinishedMessage
 
-        self._start_slice_job = None
+        self._start_slice_job = None #type: Optional[StartSliceJob]
-        self._start_slice_job_build_plate = None
+        self._start_slice_job_build_plate = None #type: Optional[int]
-        self._slicing = False  # Are we currently slicing?
+        self._slicing = False #type: bool # Are we currently slicing?
-        self._restart = False  # Back-end is currently restarting?
+        self._restart = False #type: bool # Back-end is currently restarting?
-        self._tool_active = False  # If a tool is active, some tasks do not have to do anything
+        self._tool_active = False #type: bool # If a tool is active, some tasks do not have to do anything
-        self._always_restart = True  # Always restart the engine when starting a new slice. Don't keep the process running. TODO: Fix engine statelessness.
+        self._always_restart = True #type: bool # Always restart the engine when starting a new slice. Don't keep the process running. TODO: Fix engine statelessness.
-        self._process_layers_job = None  # The currently active job to process layers, or None if it is not processing layers.
+        self._process_layers_job = None #type: Optional[ProcessSlicedLayersJob] # The currently active job to process layers, or None if it is not processing layers.
-        self._build_plates_to_be_sliced = []  # what needs slicing?
+        self._build_plates_to_be_sliced = [] #type: List[int] # what needs slicing?
-        self._engine_is_fresh = True  # Is the newly started engine used before or not?
+        self._engine_is_fresh = True #type: bool # Is the newly started engine used before or not?
 
-        self._backend_log_max_lines = 20000  # Maximum number of lines to buffer
+        self._backend_log_max_lines = 20000 #type: int # Maximum number of lines to buffer
-        self._error_message = None  # Pop-up message that shows errors.
+        self._error_message = None #type: Message # Pop-up message that shows errors.
-        self._last_num_objects = defaultdict(int)  # Count number of objects to see if there is something changed
+        self._last_num_objects = defaultdict(int) #type: Dict[int, int] # Count number of objects to see if there is something changed
-        self._postponed_scene_change_sources = []  # scene change is postponed (by a tool)
+        self._postponed_scene_change_sources = [] #type: List[SceneNode] # scene change is postponed (by a tool)
 
-        self._slice_start_time = None
+        self._slice_start_time = None #type: Optional[float]
-        self._is_disabled = False
+        self._is_disabled = False #type: bool
 
-        Application.getInstance().getPreferences().addPreference("general/auto_slice", False)
+        self._application.getPreferences().addPreference("general/auto_slice", False)
 
-        self._use_timer = False
+        self._use_timer = False #type: bool
         # When you update a setting and other settings get changed through inheritance, many propertyChanged signals are fired.
         # This timer will group them up, and only slice for the last setting changed signal.
         # TODO: Properly group propertyChanged signals by whether they are triggered by the same user interaction.
-        self._change_timer = QTimer()
+        self._change_timer = QTimer() #type: QTimer
         self._change_timer.setSingleShot(True)
         self._change_timer.setInterval(500)
         self.determineAutoSlicing()
-        Application.getInstance().getPreferences().preferenceChanged.connect(self._onPreferencesChanged)
+        self._application.getPreferences().preferenceChanged.connect(self._onPreferencesChanged)
 
         self._application.initializationFinished.connect(self.initialize)
 
-    def initialize(self):
+    def initialize(self) -> None:
         self._multi_build_plate_model = self._application.getMultiBuildPlateModel()
 
         self._application.getController().activeViewChanged.connect(self._onActiveViewChanged)
@@ -160,16 +167,16 @@ class CuraEngineBackend(QObject, Backend):
     #
     #   This function should terminate the engine process.
     #   Called when closing the application.
-    def close(self):
+    def close(self) -> None:
         # Terminate CuraEngine if it is still running at this point
         self._terminate()
 
     ##  Get the command that is used to call the engine.
     #   This is useful for debugging and used to actually start the engine.
     #   \return list of commands and args / parameters.
-    def getEngineCommand(self):
+    def getEngineCommand(self) -> List[str]:
         json_path = Resources.getPath(Resources.DefinitionContainers, "fdmprinter.def.json")
-        return [Application.getInstance().getPreferences().getValue("backend/location"), "connect", "127.0.0.1:{0}".format(self._port), "-j", json_path, ""]
+        return [self._application.getPreferences().getValue("backend/location"), "connect", "127.0.0.1:{0}".format(self._port), "-j", json_path, ""]
 
     ##  Emitted when we get a message containing print duration and material amount.
     #   This also implies the slicing has finished.
@@ -184,13 +191,13 @@ class CuraEngineBackend(QObject, Backend):
     slicingCancelled = Signal()
 
     @pyqtSlot()
-    def stopSlicing(self):
+    def stopSlicing(self) -> None:
         self.backendStateChange.emit(BackendState.NotStarted)
         if self._slicing:  # We were already slicing. Stop the old job.
             self._terminate()
             self._createSocket()
 
-        if self._process_layers_job:  # We were processing layers. Stop that, the layers are going to change soon.
+        if self._process_layers_job is not None:  # We were processing layers. Stop that, the layers are going to change soon.
             Logger.log("d", "Aborting process layers job...")
             self._process_layers_job.abort()
             self._process_layers_job = None
@@ -200,12 +207,12 @@ class CuraEngineBackend(QObject, Backend):
 
     ##  Manually triggers a reslice
     @pyqtSlot()
-    def forceSlice(self):
+    def forceSlice(self) -> None:
         self.markSliceAll()
         self.slice()
 
     ##  Perform a slice of the scene.
-    def slice(self):
+    def slice(self) -> None:
         Logger.log("d", "Starting to slice...")
         self._slice_start_time = time()
         if not self._build_plates_to_be_sliced:
@@ -218,10 +225,10 @@ class CuraEngineBackend(QObject, Backend):
             return
 
         if not hasattr(self._scene, "gcode_dict"):
-            self._scene.gcode_dict = {}
+            self._scene.gcode_dict = {} #type: ignore #Because we are creating the missing attribute here.
 
         # see if we really have to slice
-        active_build_plate = Application.getInstance().getMultiBuildPlateModel().activeBuildPlate
+        active_build_plate = self._application.getMultiBuildPlateModel().activeBuildPlate
         build_plate_to_be_sliced = self._build_plates_to_be_sliced.pop(0)
         Logger.log("d", "Going to slice build plate [%s]!" % build_plate_to_be_sliced)
         num_objects = self._numObjectsPerBuildPlate()
@@ -230,14 +237,14 @@ class CuraEngineBackend(QObject, Backend):
         self._stored_optimized_layer_data[build_plate_to_be_sliced] = []
 
         if build_plate_to_be_sliced not in num_objects or num_objects[build_plate_to_be_sliced] == 0:
-            self._scene.gcode_dict[build_plate_to_be_sliced] = []
+            self._scene.gcode_dict[build_plate_to_be_sliced] = [] #type: ignore #Because we created this attribute above.
             Logger.log("d", "Build plate %s has no objects to be sliced, skipping", build_plate_to_be_sliced)
             if self._build_plates_to_be_sliced:
                 self.slice()
             return
 
-        if Application.getInstance().getPrintInformation() and build_plate_to_be_sliced == active_build_plate:
+        if self._application.getPrintInformation() and build_plate_to_be_sliced == active_build_plate:
-            Application.getInstance().getPrintInformation().setToZeroPrintInformation(build_plate_to_be_sliced)
+            self._application.getPrintInformation().setToZeroPrintInformation(build_plate_to_be_sliced)
 
         if self._process is None:
             self._createSocket()
@@ -247,14 +254,14 @@ class CuraEngineBackend(QObject, Backend):
         self.processingProgress.emit(0.0)
         self.backendStateChange.emit(BackendState.NotStarted)
 
-        self._scene.gcode_dict[build_plate_to_be_sliced] = []  #[] indexed by build plate number
+        self._scene.gcode_dict[build_plate_to_be_sliced] = [] #type: ignore #[] indexed by build plate number
         self._slicing = True
         self.slicingStarted.emit()
 
         self.determineAutoSlicing()  # Switch timer on or off if appropriate
 
         slice_message = self._socket.createMessage("cura.proto.Slice")
-        self._start_slice_job = StartSliceJob.StartSliceJob(slice_message)
+        self._start_slice_job = StartSliceJob(slice_message)
         self._start_slice_job_build_plate = build_plate_to_be_sliced
         self._start_slice_job.setBuildPlate(self._start_slice_job_build_plate)
         self._start_slice_job.start()
@@ -262,7 +269,7 @@ class CuraEngineBackend(QObject, Backend):
 
     ##  Terminate the engine process.
     #   Start the engine process by calling _createSocket()
-    def _terminate(self):
+    def _terminate(self) -> None:
         self._slicing = False
         self._stored_layer_data = []
         if self._start_slice_job_build_plate in self._stored_optimized_layer_data:
@@ -274,7 +281,7 @@ class CuraEngineBackend(QObject, Backend):
         self.processingProgress.emit(0)
         Logger.log("d", "Attempting to kill the engine process")
 
-        if Application.getInstance().getUseExternalBackend():
+        if self._application.getUseExternalBackend():
             return
 
         if self._process is not None:
@@ -295,7 +302,7 @@ class CuraEngineBackend(QObject, Backend):
     #   bootstrapping of a slice job.
     #
     #   \param job The start slice job that was just finished.
-    def _onStartSliceCompleted(self, job):
+    def _onStartSliceCompleted(self, job: StartSliceJob) -> None:
         if self._error_message:
             self._error_message.hide()
 
@@ -303,13 +310,13 @@ class CuraEngineBackend(QObject, Backend):
         if self._start_slice_job is job:
             self._start_slice_job = None
 
-        if job.isCancelled() or job.getError() or job.getResult() == StartSliceJob.StartJobResult.Error:
+        if job.isCancelled() or job.getError() or job.getResult() == StartJobResult.Error:
             self.backendStateChange.emit(BackendState.Error)
             self.backendError.emit(job)
             return
 
-        if job.getResult() == StartSliceJob.StartJobResult.MaterialIncompatible:
+        if job.getResult() == StartJobResult.MaterialIncompatible:
-            if Application.getInstance().platformActivity:
+            if self._application.platformActivity:
                 self._error_message = Message(catalog.i18nc("@info:status",
                                             "Unable to slice with the current material as it is incompatible with the selected machine or configuration."), title = catalog.i18nc("@info:title", "Unable to slice"))
                 self._error_message.show()
@@ -319,10 +326,10 @@ class CuraEngineBackend(QObject, Backend):
                 self.backendStateChange.emit(BackendState.NotStarted)
             return
 
-        if job.getResult() == StartSliceJob.StartJobResult.SettingError:
+        if job.getResult() == StartJobResult.SettingError:
-            if Application.getInstance().platformActivity:
+            if self._application.platformActivity:
                 extruders = list(ExtruderManager.getInstance().getMachineExtruders(self._global_container_stack.getId()))
-                error_keys = []
+                error_keys = [] #type: List[str]
                 for extruder in extruders:
                     error_keys.extend(extruder.getErrorKeys())
                 if not extruders:
@@ -330,7 +337,7 @@ class CuraEngineBackend(QObject, Backend):
                 error_labels = set()
                 for key in error_keys:
                     for stack in [self._global_container_stack] + extruders: #Search all container stacks for the definition of this setting. Some are only in an extruder stack.
-                        definitions = stack.getBottom().findDefinitions(key = key)
+                        definitions = cast(DefinitionContainerInterface, stack.getBottom()).findDefinitions(key = key)
                         if definitions:
                             break #Found it! No need to continue search.
                     else: #No stack has a definition for this setting.
@@ -338,8 +345,7 @@ class CuraEngineBackend(QObject, Backend):
                         continue
                     error_labels.add(definitions[0].label)
 
-                error_labels = ", ".join(error_labels)
+                self._error_message = Message(catalog.i18nc("@info:status", "Unable to slice with the current settings. The following settings have errors: {0}").format(", ".join(error_labels)),
-                self._error_message = Message(catalog.i18nc("@info:status", "Unable to slice with the current settings. The following settings have errors: {0}").format(error_labels),
                                               title = catalog.i18nc("@info:title", "Unable to slice"))
                 self._error_message.show()
                 self.backendStateChange.emit(BackendState.Error)
@@ -348,29 +354,27 @@ class CuraEngineBackend(QObject, Backend):
                 self.backendStateChange.emit(BackendState.NotStarted)
             return
 
-        elif job.getResult() == StartSliceJob.StartJobResult.ObjectSettingError:
+        elif job.getResult() == StartJobResult.ObjectSettingError:
             errors = {}
-            for node in DepthFirstIterator(Application.getInstance().getController().getScene().getRoot()):
+            for node in DepthFirstIterator(self._application.getController().getScene().getRoot()): #type: ignore #Ignore type error because iter() should get called automatically by Python syntax.
                 stack = node.callDecoration("getStack")
                 if not stack:
                     continue
                 for key in stack.getErrorKeys():
-                    definition = self._global_container_stack.getBottom().findDefinitions(key = key)
+                    definition = cast(DefinitionContainerInterface, self._global_container_stack.getBottom()).findDefinitions(key = key)
                     if not definition:
                         Logger.log("e", "When checking settings for errors, unable to find definition for key {key} in per-object stack.".format(key = key))
                         continue
-                    definition = definition[0]
+                    errors[key] = definition[0].label
-                    errors[key] = definition.label
+            self._error_message = Message(catalog.i18nc("@info:status", "Unable to slice due to some per-model settings. The following settings have errors on one or more models: {error_labels}").format(error_labels = ", ".join(errors.values())),
-            error_labels = ", ".join(errors.values())
-            self._error_message = Message(catalog.i18nc("@info:status", "Unable to slice due to some per-model settings. The following settings have errors on one or more models: {error_labels}").format(error_labels = error_labels),
                                           title = catalog.i18nc("@info:title", "Unable to slice"))
             self._error_message.show()
             self.backendStateChange.emit(BackendState.Error)
             self.backendError.emit(job)
             return
 
-        if job.getResult() == StartSliceJob.StartJobResult.BuildPlateError:
+        if job.getResult() == StartJobResult.BuildPlateError:
-            if Application.getInstance().platformActivity:
+            if self._application.platformActivity:
                 self._error_message = Message(catalog.i18nc("@info:status", "Unable to slice because the prime tower or prime position(s) are invalid."),
                                               title = catalog.i18nc("@info:title", "Unable to slice"))
                 self._error_message.show()
@@ -379,7 +383,7 @@ class CuraEngineBackend(QObject, Backend):
             else:
                 self.backendStateChange.emit(BackendState.NotStarted)
 
-        if job.getResult() == StartSliceJob.StartJobResult.ObjectsWithDisabledExtruder:
+        if job.getResult() == StartJobResult.ObjectsWithDisabledExtruder:
             self._error_message = Message(catalog.i18nc("@info:status", "Unable to slice because there are objects associated with disabled Extruder %s." % job.getMessage()),
                                           title = catalog.i18nc("@info:title", "Unable to slice"))
             self._error_message.show()
@@ -387,8 +391,8 @@ class CuraEngineBackend(QObject, Backend):
             self.backendError.emit(job)
             return
 
-        if job.getResult() == StartSliceJob.StartJobResult.NothingToSlice:
+        if job.getResult() == StartJobResult.NothingToSlice:
-            if Application.getInstance().platformActivity:
+            if self._application.platformActivity:
                 self._error_message = Message(catalog.i18nc("@info:status", "Nothing to slice because none of the models fit the build volume. Please scale or rotate models to fit."),
                                               title = catalog.i18nc("@info:title", "Unable to slice"))
                 self._error_message.show()
@@ -411,20 +415,20 @@ class CuraEngineBackend(QObject, Backend):
     #   It disables when
     #   - preference auto slice is off
     #   - decorator isBlockSlicing is found (used in g-code reader)
-    def determineAutoSlicing(self):
+    def determineAutoSlicing(self) -> bool:
         enable_timer = True
         self._is_disabled = False
 
-        if not Application.getInstance().getPreferences().getValue("general/auto_slice"):
+        if not self._application.getPreferences().getValue("general/auto_slice"):
             enable_timer = False
-        for node in DepthFirstIterator(self._scene.getRoot()):
+        for node in DepthFirstIterator(self._scene.getRoot()): #type: ignore #Ignore type error because iter() should get called automatically by Python syntax.
             if node.callDecoration("isBlockSlicing"):
                 enable_timer = False
                 self.backendStateChange.emit(BackendState.Disabled)
                 self._is_disabled = True
             gcode_list = node.callDecoration("getGCodeList")
             if gcode_list is not None:
-                self._scene.gcode_dict[node.callDecoration("getBuildPlateNumber")] = gcode_list
+                self._scene.gcode_dict[node.callDecoration("getBuildPlateNumber")] = gcode_list #type: ignore #Because we generate this attribute dynamically.
 
         if self._use_timer == enable_timer:
             return self._use_timer
@@ -437,9 +441,9 @@ class CuraEngineBackend(QObject, Backend):
             return False
 
     ##  Return a dict with number of objects per build plate
-    def _numObjectsPerBuildPlate(self):
+    def _numObjectsPerBuildPlate(self) -> Dict[int, int]:
-        num_objects = defaultdict(int)
+        num_objects = defaultdict(int) #type: Dict[int, int]
-        for node in DepthFirstIterator(self._scene.getRoot()):
+        for node in DepthFirstIterator(self._scene.getRoot()): #type: ignore #Ignore type error because iter() should get called automatically by Python syntax.
             # Only count sliceable objects
             if node.callDecoration("isSliceable"):
                 build_plate_number = node.callDecoration("getBuildPlateNumber")
@@ -451,7 +455,7 @@ class CuraEngineBackend(QObject, Backend):
     #   This should start a slice if the scene is now ready to slice.
     #
     #   \param source The scene node that was changed.
-    def _onSceneChanged(self, source):
+    def _onSceneChanged(self, source: SceneNode) -> None:
         if not isinstance(source, SceneNode):
             return
 
@@ -506,8 +510,8 @@ class CuraEngineBackend(QObject, Backend):
     ##  Called when an error occurs in the socket connection towards the engine.
     #
     #   \param error The exception that occurred.
-    def _onSocketError(self, error):
+    def _onSocketError(self, error: Arcus.Error) -> None:
-        if Application.getInstance().isShuttingDown():
+        if self._application.isShuttingDown():
             return
 
         super()._onSocketError(error)
@@ -521,19 +525,19 @@ class CuraEngineBackend(QObject, Backend):
             Logger.log("w", "A socket error caused the connection to be reset")
 
     ##  Remove old layer data (if any)
-    def _clearLayerData(self, build_plate_numbers = set()):
+    def _clearLayerData(self, build_plate_numbers: Set = None) -> None:
-        for node in DepthFirstIterator(self._scene.getRoot()):
+        for node in DepthFirstIterator(self._scene.getRoot()): #type: ignore #Ignore type error because iter() should get called automatically by Python syntax.
             if node.callDecoration("getLayerData"):
                 if not build_plate_numbers or node.callDecoration("getBuildPlateNumber") in build_plate_numbers:
                     node.getParent().removeChild(node)
 
-    def markSliceAll(self):
+    def markSliceAll(self) -> None:
-        for build_plate_number in range(Application.getInstance().getMultiBuildPlateModel().maxBuildPlate + 1):
+        for build_plate_number in range(self._application.getMultiBuildPlateModel().maxBuildPlate + 1):
             if build_plate_number not in self._build_plates_to_be_sliced:
                 self._build_plates_to_be_sliced.append(build_plate_number)
 
     ##  Convenient function: mark everything to slice, emit state and clear layer data
-    def needsSlicing(self):
+    def needsSlicing(self) -> None:
         self.stopSlicing()
         self.markSliceAll()
         self.processingProgress.emit(0.0)
@@ -545,7 +549,7 @@ class CuraEngineBackend(QObject, Backend):
     ##  A setting has changed, so check if we must reslice.
     # \param instance The setting instance that has changed.
     # \param property The property of the setting instance that has changed.
-    def _onSettingChanged(self, instance, property):
+    def _onSettingChanged(self, instance: SettingInstance, property: str) -> None:
         if property == "value":  # Only reslice if the value has changed.
             self.needsSlicing()
             self._onChanged()
@@ -554,7 +558,7 @@ class CuraEngineBackend(QObject, Backend):
             if self._use_timer:
                 self._change_timer.stop()
 
-    def _onStackErrorCheckFinished(self):
+    def _onStackErrorCheckFinished(self) -> None:
         self.determineAutoSlicing()
         if self._is_disabled:
             return
@@ -566,13 +570,13 @@ class CuraEngineBackend(QObject, Backend):
     ##  Called when a sliced layer data message is received from the engine.
     #
     #   \param message The protobuf message containing sliced layer data.
-    def _onLayerMessage(self, message):
+    def _onLayerMessage(self, message: Arcus.PythonMessage) -> None:
         self._stored_layer_data.append(message)
 
     ##  Called when an optimized sliced layer data message is received from the engine.
     #
     #   \param message The protobuf message containing sliced layer data.
-    def _onOptimizedLayerMessage(self, message):
+    def _onOptimizedLayerMessage(self, message: Arcus.PythonMessage) -> None:
         if self._start_slice_job_build_plate not in self._stored_optimized_layer_data:
             self._stored_optimized_layer_data[self._start_slice_job_build_plate] = []
         self._stored_optimized_layer_data[self._start_slice_job_build_plate].append(message)
@@ -580,11 +584,11 @@ class CuraEngineBackend(QObject, Backend):
     ##  Called when a progress message is received from the engine.
     #
     #   \param message The protobuf message containing the slicing progress.
-    def _onProgressMessage(self, message):
+    def _onProgressMessage(self, message: Arcus.PythonMessage) -> None:
         self.processingProgress.emit(message.amount)
         self.backendStateChange.emit(BackendState.Processing)
 
-    def _invokeSlice(self):
+    def _invokeSlice(self) -> None:
         if self._use_timer:
             # if the error check is scheduled, wait for the error check finish signal to trigger auto-slice,
             # otherwise business as usual
@@ -600,17 +604,17 @@ class CuraEngineBackend(QObject, Backend):
     ##  Called when the engine sends a message that slicing is finished.
     #
     #   \param message The protobuf message signalling that slicing is finished.
-    def _onSlicingFinishedMessage(self, message):
+    def _onSlicingFinishedMessage(self, message: Arcus.PythonMessage) -> None:
         self.backendStateChange.emit(BackendState.Done)
         self.processingProgress.emit(1.0)
 
-        gcode_list = self._scene.gcode_dict[self._start_slice_job_build_plate]
+        gcode_list = self._scene.gcode_dict[self._start_slice_job_build_plate] #type: ignore #Because we generate this attribute dynamically.
         for index, line in enumerate(gcode_list):
-            replaced = line.replace("{print_time}", str(Application.getInstance().getPrintInformation().currentPrintTime.getDisplayString(DurationFormat.Format.ISO8601)))
+            replaced = line.replace("{print_time}", str(self._application.getPrintInformation().currentPrintTime.getDisplayString(DurationFormat.Format.ISO8601)))
-            replaced = replaced.replace("{filament_amount}", str(Application.getInstance().getPrintInformation().materialLengths))
+            replaced = replaced.replace("{filament_amount}", str(self._application.getPrintInformation().materialLengths))
-            replaced = replaced.replace("{filament_weight}", str(Application.getInstance().getPrintInformation().materialWeights))
+            replaced = replaced.replace("{filament_weight}", str(self._application.getPrintInformation().materialWeights))
-            replaced = replaced.replace("{filament_cost}", str(Application.getInstance().getPrintInformation().materialCosts))
+            replaced = replaced.replace("{filament_cost}", str(self._application.getPrintInformation().materialCosts))
-            replaced = replaced.replace("{jobname}", str(Application.getInstance().getPrintInformation().jobName))
+            replaced = replaced.replace("{jobname}", str(self._application.getPrintInformation().jobName))
 
             gcode_list[index] = replaced
 
@@ -619,7 +623,7 @@ class CuraEngineBackend(QObject, Backend):
         Logger.log("d", "Number of models per buildplate: %s", dict(self._numObjectsPerBuildPlate()))
 
         # See if we need to process the sliced layers job.
-        active_build_plate = Application.getInstance().getMultiBuildPlateModel().activeBuildPlate
+        active_build_plate = self._application.getMultiBuildPlateModel().activeBuildPlate
         if (
             self._layer_view_active and
             (self._process_layers_job is None or not self._process_layers_job.isRunning()) and
@@ -641,25 +645,27 @@ class CuraEngineBackend(QObject, Backend):
     ##  Called when a g-code message is received from the engine.
     #
     #   \param message The protobuf message containing g-code, encoded as UTF-8.
-    def _onGCodeLayerMessage(self, message):
+    def _onGCodeLayerMessage(self, message: Arcus.PythonMessage) -> None:
-        self._scene.gcode_dict[self._start_slice_job_build_plate].append(message.data.decode("utf-8", "replace"))
+        self._scene.gcode_dict[self._start_slice_job_build_plate].append(message.data.decode("utf-8", "replace")) #type: ignore #Because we generate this attribute dynamically.
 
     ##  Called when a g-code prefix message is received from the engine.
     #
     #   \param message The protobuf message containing the g-code prefix,
     #   encoded as UTF-8.
-    def _onGCodePrefixMessage(self, message):
+    def _onGCodePrefixMessage(self, message: Arcus.PythonMessage) -> None:
-        self._scene.gcode_dict[self._start_slice_job_build_plate].insert(0, message.data.decode("utf-8", "replace"))
+        self._scene.gcode_dict[self._start_slice_job_build_plate].insert(0, message.data.decode("utf-8", "replace")) #type: ignore #Because we generate this attribute dynamically.
 
     ##  Creates a new socket connection.
-    def _createSocket(self):
+    def _createSocket(self, protocol_file: str = None) -> None:
-        super()._createSocket(os.path.abspath(os.path.join(PluginRegistry.getInstance().getPluginPath(self.getPluginId()), "Cura.proto")))
+        if not protocol_file:
+            protocol_file = os.path.abspath(os.path.join(PluginRegistry.getInstance().getPluginPath(self.getPluginId()), "Cura.proto"))
+        super()._createSocket(protocol_file)
         self._engine_is_fresh = True
 
     ##  Called when anything has changed to the stuff that needs to be sliced.
     #
     #   This indicates that we should probably re-slice soon.
-    def _onChanged(self, *args, **kwargs):
+    def _onChanged(self, *args: Any, **kwargs: Any) -> None:
         self.needsSlicing()
         if self._use_timer:
             # if the error check is scheduled, wait for the error check finish signal to trigger auto-slice,
@@ -677,7 +683,7 @@ class CuraEngineBackend(QObject, Backend):
     #
     #   \param message The protobuf message containing the print time per feature and
     #   material amount per extruder
-    def _onPrintTimeMaterialEstimates(self, message):
+    def _onPrintTimeMaterialEstimates(self, message: Arcus.PythonMessage) -> None:
         material_amounts = []
         for index in range(message.repeatedMessageCount("materialEstimates")):
             material_amounts.append(message.getRepeatedMessage("materialEstimates", index).material_amount)
@@ -688,7 +694,7 @@ class CuraEngineBackend(QObject, Backend):
     ##  Called for parsing message to retrieve estimated time per feature
     #
     #   \param message The protobuf message containing the print time per feature
-    def _parseMessagePrintTimes(self, message):
+    def _parseMessagePrintTimes(self, message: Arcus.PythonMessage) -> Dict[str, float]:
         result = {
             "inset_0": message.time_inset_0,
             "inset_x": message.time_inset_x,
@@ -705,7 +711,7 @@ class CuraEngineBackend(QObject, Backend):
         return result
 
     ##  Called when the back-end connects to the front-end.
-    def _onBackendConnected(self):
+    def _onBackendConnected(self) -> None:
         if self._restart:
             self._restart = False
             self._onChanged()
@@ -716,7 +722,7 @@ class CuraEngineBackend(QObject, Backend):
     #   continuously slicing while the user is dragging some tool handle.
     #
     #   \param tool The tool that the user is using.
-    def _onToolOperationStarted(self, tool):
+    def _onToolOperationStarted(self, tool: Tool) -> None:
         self._tool_active = True  # Do not react on scene change
         self.disableTimer()
         # Restart engine as soon as possible, we know we want to slice afterwards
@@ -729,7 +735,7 @@ class CuraEngineBackend(QObject, Backend):
     #   This indicates that we can safely start slicing again.
     #
     #   \param tool The tool that the user was using.
-    def _onToolOperationStopped(self, tool):
+    def _onToolOperationStopped(self, tool: Tool) -> None:
         self._tool_active = False  # React on scene change again
         self.determineAutoSlicing()  # Switch timer on if appropriate
         # Process all the postponed scene changes
@@ -737,18 +743,17 @@ class CuraEngineBackend(QObject, Backend):
             source = self._postponed_scene_change_sources.pop(0)
             self._onSceneChanged(source)
 
-    def _startProcessSlicedLayersJob(self, build_plate_number):
+    def _startProcessSlicedLayersJob(self, build_plate_number: int) -> None:
-        self._process_layers_job = ProcessSlicedLayersJob.ProcessSlicedLayersJob(self._stored_optimized_layer_data[build_plate_number])
+        self._process_layers_job = ProcessSlicedLayersJob(self._stored_optimized_layer_data[build_plate_number])
         self._process_layers_job.setBuildPlate(build_plate_number)
         self._process_layers_job.finished.connect(self._onProcessLayersFinished)
         self._process_layers_job.start()
 
     ##  Called when the user changes the active view mode.
-    def _onActiveViewChanged(self):
+    def _onActiveViewChanged(self) -> None:
-        application = Application.getInstance()
+        view = self._application.getController().getActiveView()
-        view = application.getController().getActiveView()
         if view:
-            active_build_plate = application.getMultiBuildPlateModel().activeBuildPlate
+            active_build_plate = self._application.getMultiBuildPlateModel().activeBuildPlate
             if view.getPluginId() == "SimulationView":  # If switching to layer view, we should process the layers if that hasn't been done yet.
                 self._layer_view_active = True
                 # There is data and we're not slicing at the moment
@@ -766,14 +771,14 @@ class CuraEngineBackend(QObject, Backend):
     ##  Called when the back-end self-terminates.
     #
     #   We should reset our state and start listening for new connections.
-    def _onBackendQuit(self):
+    def _onBackendQuit(self) -> None:
         if not self._restart:
             if self._process:
                 Logger.log("d", "Backend quit with return code %s. Resetting process and socket.", self._process.wait())
                 self._process = None
 
     ##  Called when the global container stack changes
-    def _onGlobalStackChanged(self):
+    def _onGlobalStackChanged(self) -> None:
         if self._global_container_stack:
             self._global_container_stack.propertyChanged.disconnect(self._onSettingChanged)
             self._global_container_stack.containersChanged.disconnect(self._onChanged)
@@ -783,7 +788,7 @@ class CuraEngineBackend(QObject, Backend):
                 extruder.propertyChanged.disconnect(self._onSettingChanged)
                 extruder.containersChanged.disconnect(self._onChanged)
 
-        self._global_container_stack = Application.getInstance().getGlobalContainerStack()
+        self._global_container_stack = self._application.getGlobalContainerStack()
 
         if self._global_container_stack:
             self._global_container_stack.propertyChanged.connect(self._onSettingChanged)  # Note: Only starts slicing when the value changed.
@@ -794,26 +799,26 @@ class CuraEngineBackend(QObject, Backend):
                 extruder.containersChanged.connect(self._onChanged)
             self._onChanged()
 
-    def _onProcessLayersFinished(self, job):
+    def _onProcessLayersFinished(self, job: ProcessSlicedLayersJob) -> None:
         del self._stored_optimized_layer_data[job.getBuildPlate()]
         self._process_layers_job = None
         Logger.log("d", "See if there is more to slice(2)...")
         self._invokeSlice()
 
     ##  Connect slice function to timer.
-    def enableTimer(self):
+    def enableTimer(self) -> None:
         if not self._use_timer:
             self._change_timer.timeout.connect(self.slice)
             self._use_timer = True
 
     ##  Disconnect slice function from timer.
     #   This means that slicing will not be triggered automatically
-    def disableTimer(self):
+    def disableTimer(self) -> None:
         if self._use_timer:
             self._use_timer = False
             self._change_timer.timeout.disconnect(self.slice)
 
-    def _onPreferencesChanged(self, preference):
+    def _onPreferencesChanged(self, preference: str) -> None:
         if preference != "general/auto_slice":
             return
         auto_slice = self.determineAutoSlicing()
@@ -821,11 +826,11 @@ class CuraEngineBackend(QObject, Backend):
             self._change_timer.start()
 
     ##   Tickle the backend so in case of auto slicing, it starts the timer.
-    def tickle(self):
+    def tickle(self) -> None:
         if self._use_timer:
             self._change_timer.start()
 
-    def _extruderChanged(self):
+    def _extruderChanged(self) -> None:
         for build_plate_number in range(self._multi_build_plate_model.maxBuildPlate + 1):
             if build_plate_number not in self._build_plates_to_be_sliced:
                 self._build_plates_to_be_sliced.append(build_plate_number)

plugins/CuraEngineBackend/StartSliceJob.py

@@ -1,21 +1,25 @@
-# Copyright (c) 2017 Ultimaker B.V.
+# Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
 
 import numpy
 from string import Formatter
 from enum import IntEnum
 import time
+from typing import Any, Dict, List, Optional, Set
 import re
+import Arcus #For typing.
 
 from UM.Job import Job
-from UM.Application import Application
 from UM.Logger import Logger
+from UM.Settings.ContainerStack import ContainerStack #For typing.
+from UM.Settings.SettingRelation import SettingRelation #For typing.
 
 from UM.Scene.Iterator.DepthFirstIterator import DepthFirstIterator
-
+from UM.Scene.Scene import Scene #For typing.
 from UM.Settings.Validator import ValidatorState
 from UM.Settings.SettingRelation import RelationType
 
+from cura.CuraApplication import CuraApplication
 from cura.Scene.CuraSceneNode import CuraSceneNode
 from cura.OneAtATimeIterator import OneAtATimeIterator
 from cura.Settings.ExtruderManager import ExtruderManager
@@ -35,19 +39,19 @@ class StartJobResult(IntEnum):
     ObjectsWithDisabledExtruder = 8
 
 
-##  Formatter class that handles token expansion in start/end gcod
+##  Formatter class that handles token expansion in start/end gcode
 class GcodeStartEndFormatter(Formatter):
-    def get_value(self, key, args, kwargs):  # [CodeStyle: get_value is an overridden function from the Formatter class]
+    def get_value(self, key: str, *args: str, **kwargs) -> str: #type: ignore # [CodeStyle: get_value is an overridden function from the Formatter class]
         # The kwargs dictionary contains a dictionary for each stack (with a string of the extruder_nr as their key),
         # and a default_extruder_nr to use when no extruder_nr is specified
 
         if isinstance(key, str):
             try:
-                extruder_nr = kwargs["default_extruder_nr"]
+                extruder_nr = int(kwargs["default_extruder_nr"])
             except ValueError:
                 extruder_nr = -1
 
-            key_fragments = [fragment.strip() for fragment in key.split(',')]
+            key_fragments = [fragment.strip() for fragment in key.split(",")]
             if len(key_fragments) == 2:
                 try:
                     extruder_nr = int(key_fragments[1])
@@ -74,25 +78,25 @@ class GcodeStartEndFormatter(Formatter):
 
 ##  Job class that builds up the message of scene data to send to CuraEngine.
 class StartSliceJob(Job):
-    def __init__(self, slice_message):
+    def __init__(self, slice_message: Arcus.PythonMessage) -> None:
         super().__init__()
 
-        self._scene = Application.getInstance().getController().getScene()
+        self._scene = CuraApplication.getInstance().getController().getScene() #type: Scene
-        self._slice_message = slice_message
+        self._slice_message = slice_message #type: Arcus.PythonMessage
-        self._is_cancelled = False
+        self._is_cancelled = False #type: bool
-        self._build_plate_number = None
+        self._build_plate_number = None #type: Optional[int]
 
-        self._all_extruders_settings = None # cache for all setting values from all stacks (global & extruder) for the current machine
+        self._all_extruders_settings = None #type: Optional[Dict[str, Any]] # cache for all setting values from all stacks (global & extruder) for the current machine
 
-    def getSliceMessage(self):
+    def getSliceMessage(self) -> Arcus.PythonMessage:
         return self._slice_message
 
-    def setBuildPlate(self, build_plate_number):
+    def setBuildPlate(self, build_plate_number: int) -> None:
         self._build_plate_number = build_plate_number
 
     ##  Check if a stack has any errors.
     ##  returns true if it has errors, false otherwise.
-    def _checkStackForErrors(self, stack):
+    def _checkStackForErrors(self, stack: ContainerStack) -> bool:
         if stack is None:
             return False
 
@@ -105,28 +109,28 @@ class StartSliceJob(Job):
         return False
 
     ##  Runs the job that initiates the slicing.
-    def run(self):
+    def run(self) -> None:
         if self._build_plate_number is None:
             self.setResult(StartJobResult.Error)
             return
 
-        stack = Application.getInstance().getGlobalContainerStack()
+        stack = CuraApplication.getInstance().getGlobalContainerStack()
         if not stack:
             self.setResult(StartJobResult.Error)
             return
 
         # Don't slice if there is a setting with an error value.
-        if Application.getInstance().getMachineManager().stacksHaveErrors:
+        if CuraApplication.getInstance().getMachineManager().stacksHaveErrors:
             self.setResult(StartJobResult.SettingError)
             return
 
-        if Application.getInstance().getBuildVolume().hasErrors():
+        if CuraApplication.getInstance().getBuildVolume().hasErrors():
             self.setResult(StartJobResult.BuildPlateError)
             return
 
         # Don't slice if the buildplate or the nozzle type is incompatible with the materials
-        if not Application.getInstance().getMachineManager().variantBuildplateCompatible and \
+        if not CuraApplication.getInstance().getMachineManager().variantBuildplateCompatible and \
-                not Application.getInstance().getMachineManager().variantBuildplateUsable:
+                not CuraApplication.getInstance().getMachineManager().variantBuildplateUsable:
             self.setResult(StartJobResult.MaterialIncompatible)
             return
 
@@ -141,7 +145,7 @@ class StartSliceJob(Job):
 
 
         # Don't slice if there is a per object setting with an error value.
-        for node in DepthFirstIterator(self._scene.getRoot()):
+        for node in DepthFirstIterator(self._scene.getRoot()): #type: ignore #Ignore type error because iter() should get called automatically by Python syntax.
             if not isinstance(node, CuraSceneNode) or not node.isSelectable():
                 continue
 
@@ -151,7 +155,7 @@ class StartSliceJob(Job):
 
         with self._scene.getSceneLock():
             # Remove old layer data.
-            for node in DepthFirstIterator(self._scene.getRoot()):
+            for node in DepthFirstIterator(self._scene.getRoot()): #type: ignore #Ignore type error because iter() should get called automatically by Python syntax.
                 if node.callDecoration("getLayerData") and node.callDecoration("getBuildPlateNumber") == self._build_plate_number:
                     node.getParent().removeChild(node)
                     break
@@ -159,7 +163,7 @@ class StartSliceJob(Job):
             # Get the objects in their groups to print.
             object_groups = []
             if stack.getProperty("print_sequence", "value") == "one_at_a_time":
-                for node in OneAtATimeIterator(self._scene.getRoot()):
+                for node in OneAtATimeIterator(self._scene.getRoot()): #type: ignore #Ignore type error because iter() should get called automatically by Python syntax.
                     temp_list = []
 
                     # Node can't be printed, so don't bother sending it.
@@ -185,7 +189,7 @@ class StartSliceJob(Job):
             else:
                 temp_list = []
                 has_printing_mesh = False
-                for node in DepthFirstIterator(self._scene.getRoot()):
+                for node in DepthFirstIterator(self._scene.getRoot()): #type: ignore #Ignore type error because iter() should get called automatically by Python syntax.
                     if node.callDecoration("isSliceable") and node.getMeshData() and node.getMeshData().getVertices() is not None:
                         per_object_stack = node.callDecoration("getStack")
                         is_non_printing_mesh = False
@@ -212,12 +216,12 @@ class StartSliceJob(Job):
                 if temp_list:
                     object_groups.append(temp_list)
 
-            extruders_enabled = {position: stack.isEnabled for position, stack in Application.getInstance().getGlobalContainerStack().extruders.items()}
+            extruders_enabled = {position: stack.isEnabled for position, stack in CuraApplication.getInstance().getGlobalContainerStack().extruders.items()}
             filtered_object_groups = []
             has_model_with_disabled_extruders = False
             associated_disabled_extruders = set()
             for group in object_groups:
-                stack = Application.getInstance().getGlobalContainerStack()
+                stack = CuraApplication.getInstance().getGlobalContainerStack()
                 skip_group = False
                 for node in group:
                     extruder_position = node.callDecoration("getActiveExtruderPosition")
@@ -283,11 +287,11 @@ class StartSliceJob(Job):
 
         self.setResult(StartJobResult.Finished)
 
-    def cancel(self):
+    def cancel(self) -> None:
         super().cancel()
         self._is_cancelled = True
 
-    def isCancelled(self):
+    def isCancelled(self) -> bool:
         return self._is_cancelled
 
     ##  Creates a dictionary of tokens to replace in g-code pieces.
@@ -297,7 +301,7 @@ class StartSliceJob(Job):
     #   with.
     #   \return A dictionary of replacement tokens to the values they should be
     #   replaced with.
-    def _buildReplacementTokens(self, stack) -> dict:
+    def _buildReplacementTokens(self, stack: ContainerStack) -> Dict[str, Any]:
         result = {}
         for key in stack.getAllKeys():
             value = stack.getProperty(key, "value")
@@ -310,7 +314,7 @@ class StartSliceJob(Job):
         result["date"] = time.strftime("%d-%m-%Y")
         result["day"] = ["Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"][int(time.strftime("%w"))]
 
-        initial_extruder_stack = Application.getInstance().getExtruderManager().getUsedExtruderStacks()[0]
+        initial_extruder_stack = CuraApplication.getInstance().getExtruderManager().getUsedExtruderStacks()[0]
         initial_extruder_nr = initial_extruder_stack.getProperty("extruder_nr", "value")
         result["initial_extruder_nr"] = initial_extruder_nr
 
@@ -319,9 +323,9 @@ class StartSliceJob(Job):
     ##  Replace setting tokens in a piece of g-code.
     #   \param value A piece of g-code to replace tokens in.
     #   \param default_extruder_nr Stack nr to use when no stack nr is specified, defaults to the global stack
-    def _expandGcodeTokens(self, value: str, default_extruder_nr: int = -1):
+    def _expandGcodeTokens(self, value: str, default_extruder_nr: int = -1) -> str:
         if not self._all_extruders_settings:
-            global_stack = Application.getInstance().getGlobalContainerStack()
+            global_stack = CuraApplication.getInstance().getGlobalContainerStack()
 
             # NB: keys must be strings for the string formatter
             self._all_extruders_settings = {
@@ -343,7 +347,7 @@ class StartSliceJob(Job):
             return str(value)
 
     ##  Create extruder message from stack
-    def _buildExtruderMessage(self, stack):
+    def _buildExtruderMessage(self, stack: ContainerStack) -> None:
         message = self._slice_message.addRepeatedMessage("extruders")
         message.id = int(stack.getMetaDataEntry("position"))
 
@@ -370,7 +374,7 @@ class StartSliceJob(Job):
     #
     #   The settings are taken from the global stack. This does not include any
     #   per-extruder settings or per-object settings.
-    def _buildGlobalSettingsMessage(self, stack):
+    def _buildGlobalSettingsMessage(self, stack: ContainerStack) -> None:
         settings = self._buildReplacementTokens(stack)
 
         # Pre-compute material material_bed_temp_prepend and material_print_temp_prepend
@@ -384,7 +388,7 @@ class StartSliceJob(Job):
 
         # Replace the setting tokens in start and end g-code.
         # Use values from the first used extruder by default so we get the expected temperatures
-        initial_extruder_stack = Application.getInstance().getExtruderManager().getUsedExtruderStacks()[0]
+        initial_extruder_stack = CuraApplication.getInstance().getExtruderManager().getUsedExtruderStacks()[0]
         initial_extruder_nr = initial_extruder_stack.getProperty("extruder_nr", "value")
 
         settings["machine_start_gcode"] = self._expandGcodeTokens(settings["machine_start_gcode"], initial_extruder_nr)
@@ -405,7 +409,7 @@ class StartSliceJob(Job):
     #
     #   \param stack The global stack with all settings, from which to read the
     #   limit_to_extruder property.
-    def _buildGlobalInheritsStackMessage(self, stack):
+    def _buildGlobalInheritsStackMessage(self, stack: ContainerStack) -> None:
         for key in stack.getAllKeys():
             extruder_position = int(round(float(stack.getProperty(key, "limit_to_extruder"))))
             if extruder_position >= 0:  # Set to a specific extruder.
@@ -415,9 +419,9 @@ class StartSliceJob(Job):
             Job.yieldThread()
 
     ##  Check if a node has per object settings and ensure that they are set correctly in the message
-    #   \param node \type{SceneNode} Node to check.
+    #   \param node Node to check.
     #   \param message object_lists message to put the per object settings in
-    def _handlePerObjectSettings(self, node, message):
+    def _handlePerObjectSettings(self, node: CuraSceneNode, message: Arcus.PythonMessage):
         stack = node.callDecoration("getStack")
 
         # Check if the node has a stack attached to it and the stack has any settings in the top container.
@@ -426,7 +430,7 @@ class StartSliceJob(Job):
 
         # Check all settings for relations, so we can also calculate the correct values for dependent settings.
         top_of_stack = stack.getTop()  # Cache for efficiency.
-        changed_setting_keys = set(top_of_stack.getAllKeys())
+        changed_setting_keys = top_of_stack.getAllKeys()
 
         # Add all relations to changed settings as well.
         for key in top_of_stack.getAllKeys():
@@ -455,9 +459,9 @@ class StartSliceJob(Job):
             Job.yieldThread()
 
     ##  Recursive function to put all settings that require each other for value changes in a list
-    #   \param relations_set \type{set} Set of keys (strings) of settings that are influenced
+    #   \param relations_set Set of keys of settings that are influenced
     #   \param relations list of relation objects that need to be checked.
-    def _addRelations(self, relations_set, relations):
+    def _addRelations(self, relations_set: Set[str], relations: List[SettingRelation]):
         for relation in filter(lambda r: r.role == "value" or r.role == "limit_to_extruder", relations):
             if relation.type == RelationType.RequiresTarget:
                 continue

plugins/GCodeGzWriter/GCodeGzWriter.py

@@ -3,7 +3,7 @@
 
 import gzip
 from io import StringIO, BufferedIOBase #To write the g-code to a temporary buffer, and for typing.
-from typing import List
+from typing import cast, List
 
 from UM.Logger import Logger
 from UM.Mesh.MeshWriter import MeshWriter #The class we're extending/implementing.
@@ -32,7 +32,7 @@ class GCodeGzWriter(MeshWriter):
 
         #Get the g-code from the g-code writer.
         gcode_textio = StringIO() #We have to convert the g-code into bytes.
-        success = PluginRegistry.getInstance().getPluginObject("GCodeWriter").write(gcode_textio, None)
+        success = cast(MeshWriter, PluginRegistry.getInstance().getPluginObject("GCodeWriter")).write(gcode_textio, None)
         if not success: #Writing the g-code failed. Then I can also not write the gzipped g-code.
             return False
 

plugins/GCodeReader/FlavorParser.py

@@ -1,11 +1,9 @@
 # Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
 
-from UM.Application import Application
 from UM.Backend import Backend
 from UM.Job import Job
 from UM.Logger import Logger
-from UM.Math.AxisAlignedBox import AxisAlignedBox
 from UM.Math.Vector import Vector
 from UM.Message import Message
 from cura.Scene.CuraSceneNode import CuraSceneNode
@@ -13,7 +11,8 @@ from UM.i18n import i18nCatalog
 
 catalog = i18nCatalog("cura")
 
-from cura import LayerDataBuilder
+from cura.CuraApplication import CuraApplication
+from cura.LayerDataBuilder import LayerDataBuilder
 from cura.LayerDataDecorator import LayerDataDecorator
 from cura.LayerPolygon import LayerPolygon
 from cura.Scene.GCodeListDecorator import GCodeListDecorator
@@ -23,16 +22,16 @@ import numpy
 import math
 import re
 from typing import Dict, List, NamedTuple, Optional, Union
-from collections import namedtuple
 
-Position = NamedTuple("Position", [("x", float), ("y", float), ("z", float), ("f", float), ("e", float)])
+PositionOptional = NamedTuple("Position", [("x", Optional[float]), ("y", Optional[float]), ("z", Optional[float]), ("f", Optional[float]), ("e", Optional[float])])
+Position = NamedTuple("Position", [("x", float), ("y", float), ("z", float), ("f", float), ("e", List[float])])
 
 ##  This parser is intended to interpret the common firmware codes among all the
 #   different flavors
 class FlavorParser:
 
     def __init__(self) -> None:
-        Application.getInstance().hideMessageSignal.connect(self._onHideMessage)
+        CuraApplication.getInstance().hideMessageSignal.connect(self._onHideMessage)
         self._cancelled = False
         self._message = None
         self._layer_number = 0
@@ -40,21 +39,21 @@ class FlavorParser:
         self._clearValues()
         self._scene_node = None
         # X, Y, Z position, F feedrate and E extruder values are stored
-        self._position = namedtuple('Position', ['x', 'y', 'z', 'f', 'e'])
+        self._position = Position
         self._is_layers_in_file = False  # Does the Gcode have the layers comment?
-        self._extruder_offsets = {}  # Offsets for multi extruders. key is index, value is [x-offset, y-offset]
+        self._extruder_offsets = {}  # type: Dict[int, List[float]] # Offsets for multi extruders. key is index, value is [x-offset, y-offset]
         self._current_layer_thickness = 0.2  # default
         self._filament_diameter = 2.85       # default
 
-        Application.getInstance().getPreferences().addPreference("gcodereader/show_caution", True)
+        CuraApplication.getInstance().getPreferences().addPreference("gcodereader/show_caution", True)
 
     def _clearValues(self) -> None:
         self._extruder_number = 0
-        self._extrusion_length_offset = [0]
+        self._extrusion_length_offset = [0] # type: List[float]
         self._layer_type = LayerPolygon.Inset0Type
         self._layer_number = 0
-        self._previous_z = 0
+        self._previous_z = 0 # type: float
-        self._layer_data_builder = LayerDataBuilder.LayerDataBuilder()
+        self._layer_data_builder = LayerDataBuilder()
         self._is_absolute_positioning = True    # It can be absolute (G90) or relative (G91)
         self._is_absolute_extrusion = True  # It can become absolute (M82, default) or relative (M83)
 
@@ -77,14 +76,14 @@ class FlavorParser:
     def _getInt(self, line: str, code: str) -> Optional[int]:
         value = self._getValue(line, code)
         try:
-            return int(value)
+            return int(value)   # type: ignore
         except:
             return None
 
     def _getFloat(self, line: str, code: str) -> Optional[float]:
         value = self._getValue(line, code)
         try:
-            return float(value)
+            return float(value) # type: ignore
         except:
             return None
 
@@ -92,10 +91,6 @@ class FlavorParser:
         if message == self._message:
             self._cancelled = True
 
-    @staticmethod
-    def _getNullBoundingBox() -> AxisAlignedBox:
-        return AxisAlignedBox(minimum=Vector(0, 0, 0), maximum=Vector(10, 10, 10))
-
     def _createPolygon(self, layer_thickness: float, path: List[List[Union[float, int]]], extruder_offsets: List[float]) -> bool:
         countvalid = 0
         for point in path:
@@ -169,7 +164,7 @@ class FlavorParser:
             return 0.35
         return line_width
 
-    def _gCode0(self, position: Position, params: Position, path: List[List[Union[float, int]]]) -> Position:
+    def _gCode0(self, position: Position, params: PositionOptional, path: List[List[Union[float, int]]]) -> Position:
         x, y, z, f, e = position
 
         if self._is_absolute_positioning:
@@ -205,7 +200,7 @@ class FlavorParser:
     _gCode1 = _gCode0
 
     ##  Home the head.
-    def _gCode28(self, position: Position, params: Position, path: List[List[Union[float, int]]]) -> Position:
+    def _gCode28(self, position: Position, params: PositionOptional, path: List[List[Union[float, int]]]) -> Position:
         return self._position(
             params.x if params.x is not None else position.x,
             params.y if params.y is not None else position.y,
@@ -214,20 +209,20 @@ class FlavorParser:
             position.e)
 
     ##  Set the absolute positioning
-    def _gCode90(self, position: Position, params: Position, path: List[List[Union[float, int]]]) -> Position:
+    def _gCode90(self, position: Position, params: PositionOptional, path: List[List[Union[float, int]]]) -> Position:
         self._is_absolute_positioning = True
         self._is_absolute_extrusion = True
         return position
 
     ##  Set the relative positioning
-    def _gCode91(self, position: Position, params: Position, path: List[List[Union[float, int]]]) -> Position:
+    def _gCode91(self, position: Position, params: PositionOptional, path: List[List[Union[float, int]]]) -> Position:
         self._is_absolute_positioning = False
         self._is_absolute_extrusion = False
         return position
 
     ##  Reset the current position to the values specified.
     #   For example: G92 X10 will set the X to 10 without any physical motion.
-    def _gCode92(self, position: Position, params: Position, path: List[List[Union[float, int]]]) -> Position:
+    def _gCode92(self, position: Position, params: PositionOptional, path: List[List[Union[float, int]]]) -> Position:
         if params.e is not None:
             # Sometimes a G92 E0 is introduced in the middle of the GCode so we need to keep those offsets for calculate the line_width
             self._extrusion_length_offset[self._extruder_number] += position.e[self._extruder_number] - params.e
@@ -260,7 +255,7 @@ class FlavorParser:
                     f = float(item[1:]) / 60
                 if item[0] == "E":
                     e = float(item[1:])
-            params = self._position(x, y, z, f, e)
+            params = PositionOptional(x, y, z, f, e)
             return func(position, params, path)
         return position
 
@@ -290,13 +285,10 @@ class FlavorParser:
         Logger.log("d", "Preparing to load GCode")
         self._cancelled = False
         # We obtain the filament diameter from the selected extruder to calculate line widths
-        global_stack = Application.getInstance().getGlobalContainerStack()
+        global_stack = CuraApplication.getInstance().getGlobalContainerStack()
         self._filament_diameter = global_stack.extruders[str(self._extruder_number)].getProperty("material_diameter", "value")
 
         scene_node = CuraSceneNode()
-        # Override getBoundingBox function of the sceneNode, as this node should return a bounding box, but there is no
-        # real data to calculate it from.
-        scene_node.getBoundingBox = self._getNullBoundingBox
 
         gcode_list = []
         self._is_layers_in_file = False
@@ -322,13 +314,14 @@ class FlavorParser:
                                 lifetime=0,
                                 title = catalog.i18nc("@info:title", "G-code Details"))
 
+        assert(self._message is not None) # use for typing purposes
         self._message.setProgress(0)
         self._message.show()
 
         Logger.log("d", "Parsing Gcode...")
 
-        current_position = self._position(0, 0, 0, 0, [0])
+        current_position = Position(0, 0, 0, 0, [0])
-        current_path = []
+        current_path = [] #type: List[List[float]]
         min_layer_number = 0
         negative_layers = 0
         previous_layer = 0
@@ -443,9 +436,9 @@ class FlavorParser:
         scene_node.addDecorator(gcode_list_decorator)
 
         # gcode_dict stores gcode_lists for a number of build plates.
-        active_build_plate_id = Application.getInstance().getMultiBuildPlateModel().activeBuildPlate
+        active_build_plate_id = CuraApplication.getInstance().getMultiBuildPlateModel().activeBuildPlate
         gcode_dict = {active_build_plate_id: gcode_list}
-        Application.getInstance().getController().getScene().gcode_dict = gcode_dict
+        CuraApplication.getInstance().getController().getScene().gcode_dict = gcode_dict #type: ignore #Because gcode_dict is generated dynamically.
 
         Logger.log("d", "Finished parsing Gcode")
         self._message.hide()
@@ -453,7 +446,7 @@ class FlavorParser:
         if self._layer_number == 0:
             Logger.log("w", "File doesn't contain any valid layers")
 
-        settings = Application.getInstance().getGlobalContainerStack()
+        settings = CuraApplication.getInstance().getGlobalContainerStack()
         if not settings.getProperty("machine_center_is_zero", "value"):
             machine_width = settings.getProperty("machine_width", "value")
             machine_depth = settings.getProperty("machine_depth", "value")
@@ -461,7 +454,7 @@ class FlavorParser:
 
         Logger.log("d", "GCode loading finished")
 
-        if Application.getInstance().getPreferences().getValue("gcodereader/show_caution"):
+        if CuraApplication.getInstance().getPreferences().getValue("gcodereader/show_caution"):
             caution_message = Message(catalog.i18nc(
                 "@info:generic",
                 "Make sure the g-code is suitable for your printer and printer configuration before sending the file to it. The g-code representation may not be accurate."),
@@ -470,7 +463,7 @@ class FlavorParser:
             caution_message.show()
 
         # The "save/print" button's state is bound to the backend state.
-        backend = Application.getInstance().getBackend()
+        backend = CuraApplication.getInstance().getBackend()
         backend.backendStateChange.emit(Backend.BackendState.Disabled)
 
         return scene_node

plugins/GCodeWriter/GCodeWriter.py

@@ -140,7 +140,7 @@ class GCodeWriter(MeshWriter):
         serialized = flat_global_container.serialize()
         data = {"global_quality": serialized}
 
-        all_setting_keys = set(flat_global_container.getAllKeys())
+        all_setting_keys = flat_global_container.getAllKeys()
         for extruder in sorted(stack.extruders.values(), key = lambda k: int(k.getMetaDataEntry("position"))):
             extruder_quality = extruder.qualityChanges
             if extruder_quality.getId() == "empty_quality_changes":
@@ -167,7 +167,7 @@ class GCodeWriter(MeshWriter):
             extruder_serialized = flat_extruder_quality.serialize()
             data.setdefault("extruder_quality", []).append(extruder_serialized)
 
-            all_setting_keys.update(set(flat_extruder_quality.getAllKeys()))
+            all_setting_keys.update(flat_extruder_quality.getAllKeys())
 
         # Check if there is any profiles
         if not all_setting_keys:

plugins/SupportEraser/SupportEraser.py

@@ -1,22 +1,17 @@
 # Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
 
-import os
-import os.path
-
 from PyQt5.QtCore import Qt, QTimer
 from PyQt5.QtWidgets import QApplication
 
 from UM.Math.Vector import Vector
 from UM.Tool import Tool
-from UM.Application import Application
 from UM.Event import Event, MouseEvent
-
 from UM.Mesh.MeshBuilder import MeshBuilder
 from UM.Scene.Selection import Selection
-from UM.Scene.Iterator.BreadthFirstIterator import BreadthFirstIterator
-from cura.Scene.CuraSceneNode import CuraSceneNode
 
+from cura.CuraApplication import CuraApplication
+from cura.Scene.CuraSceneNode import CuraSceneNode
 from cura.PickingPass import PickingPass
 
 from UM.Operations.GroupedOperation import GroupedOperation
@@ -26,8 +21,6 @@ from cura.Operations.SetParentOperation import SetParentOperation
 
 from cura.Scene.SliceableObjectDecorator import SliceableObjectDecorator
 from cura.Scene.BuildPlateDecorator import BuildPlateDecorator
-from UM.Scene.GroupDecorator import GroupDecorator
-from cura.Settings.SettingOverrideDecorator import SettingOverrideDecorator
 
 from UM.Settings.SettingInstance import SettingInstance
 
@@ -38,7 +31,7 @@ class SupportEraser(Tool):
         self._controller = self.getController()
 
         self._selection_pass = None
-        Application.getInstance().globalContainerStackChanged.connect(self._updateEnabled)
+        CuraApplication.getInstance().globalContainerStackChanged.connect(self._updateEnabled)
 
         # Note: if the selection is cleared with this tool active, there is no way to switch to
         # another tool than to reselect an object (by clicking it) because the tool buttons in the
@@ -106,7 +99,7 @@ class SupportEraser(Tool):
         mesh.addCube(10,10,10)
         node.setMeshData(mesh.build())
 
-        active_build_plate = Application.getInstance().getMultiBuildPlateModel().activeBuildPlate
+        active_build_plate = CuraApplication.getInstance().getMultiBuildPlateModel().activeBuildPlate
         node.addDecorator(BuildPlateDecorator(active_build_plate))
         node.addDecorator(SliceableObjectDecorator())
 
@@ -126,7 +119,7 @@ class SupportEraser(Tool):
         op.push()
         node.setPosition(position, CuraSceneNode.TransformSpace.World)
 
-        Application.getInstance().getController().getScene().sceneChanged.emit(node)
+        CuraApplication.getInstance().getController().getScene().sceneChanged.emit(node)
 
     def _removeEraserMesh(self, node: CuraSceneNode):
         parent = node.getParent()
@@ -139,16 +132,16 @@ class SupportEraser(Tool):
         if parent and not Selection.isSelected(parent):
             Selection.add(parent)
 
-        Application.getInstance().getController().getScene().sceneChanged.emit(node)
+        CuraApplication.getInstance().getController().getScene().sceneChanged.emit(node)
 
     def _updateEnabled(self):
         plugin_enabled = False
 
-        global_container_stack = Application.getInstance().getGlobalContainerStack()
+        global_container_stack = CuraApplication.getInstance().getGlobalContainerStack()
         if global_container_stack:
             plugin_enabled = global_container_stack.getProperty("anti_overhang_mesh", "enabled")
 
-        Application.getInstance().getController().toolEnabledChanged.emit(self._plugin_id, plugin_enabled)
+        CuraApplication.getInstance().getController().toolEnabledChanged.emit(self._plugin_id, plugin_enabled)
 
     def _onSelectionChanged(self):
         # When selection is passed from one object to another object, first the selection is cleared

plugins/Toolbox/__init__.py

@@ -9,4 +9,4 @@ def getMetaData():
 
 
 def register(app):
-    return {"extension": Toolbox.Toolbox()}
+    return {"extension": Toolbox.Toolbox(app)}

plugins/Toolbox/src/Toolbox.py

@@ -1,19 +1,20 @@
 # Copyright (c) 2018 Ultimaker B.V.
 # Toolbox is released under the terms of the LGPLv3 or higher.
 
-from typing import Dict, Optional, Union, Any
+from typing import Dict, Optional, Union, Any, cast
 import json
 import os
 import tempfile
 import platform
+from typing import List
 
 from PyQt5.QtCore import QUrl, QObject, pyqtProperty, pyqtSignal, pyqtSlot
 from PyQt5.QtNetwork import QNetworkAccessManager, QNetworkRequest, QNetworkReply
 
-from UM.Application import Application
 from UM.Logger import Logger
 from UM.PluginRegistry import PluginRegistry
 from UM.Extension import Extension
+from UM.Qt.ListModel import ListModel
 from UM.i18n import i18nCatalog
 from UM.Version import Version
 
@@ -27,44 +28,39 @@ i18n_catalog = i18nCatalog("cura")
 
 ##  The Toolbox class is responsible of communicating with the server through the API
 class Toolbox(QObject, Extension):
+    DEFAULT_CLOUD_API_ROOT = "https://api.ultimaker.com" #type: str
+    DEFAULT_CLOUD_API_VERSION = 1 #type: int
 
-    DEFAULT_CLOUD_API_ROOT = "https://api.ultimaker.com"
+    def __init__(self, application: CuraApplication) -> None:
-    DEFAULT_CLOUD_API_VERSION = 1
+        super().__init__()
 
-    def __init__(self, parent=None) -> None:
+        self._application = application #type: CuraApplication
-        super().__init__(parent)
 
-        self._application = Application.getInstance()
+        self._sdk_version = None    # type: Optional[int]
-        self._package_manager = None
+        self._cloud_api_version = None # type: Optional[int]
-        self._plugin_registry = Application.getInstance().getPluginRegistry()
+        self._cloud_api_root = None # type: Optional[str]
-
+        self._api_url = None    # type: Optional[str]
-        self._sdk_version = None
-        self._cloud_api_version = None
-        self._cloud_api_root = None
-        self._api_url = None
 
         # Network:
-        self._get_packages_request = None
+        self._download_request = None #type: Optional[QNetworkRequest]
-        self._get_showcase_request = None
+        self._download_reply = None #type: Optional[QNetworkReply]
-        self._download_request = None
+        self._download_progress = 0 #type: float
-        self._download_reply = None
+        self._is_downloading = False #type: bool
-        self._download_progress = 0
+        self._network_manager = None #type: Optional[QNetworkAccessManager]
-        self._is_downloading = False
-        self._network_manager = None
         self._request_header = [
             b"User-Agent",
             str.encode(
                 "%s/%s (%s %s)" % (
-                    Application.getInstance().getApplicationName(),
+                    self._application.getApplicationName(),
-                    Application.getInstance().getVersion(),
+                    self._application.getVersion(),
                     platform.system(),
                     platform.machine(),
                 )
             )
         ]
-        self._request_urls = {}
+        self._request_urls = {} # type: Dict[str, QUrl]
-        self._to_update = []  # Package_ids that are waiting to be updated
+        self._to_update = []  # type: List[str] # Package_ids that are waiting to be updated
-        self._old_plugin_ids = []
+        self._old_plugin_ids = [] # type: List[str]
 
         # Data:
         self._metadata = {
@@ -76,7 +72,7 @@ class Toolbox(QObject, Extension):
             "materials_showcase":  [],
             "materials_available": [],
             "materials_installed": []
-        }
+        } # type: Dict[str, List[Any]]
 
         # Models:
         self._models = {
@@ -88,33 +84,33 @@ class Toolbox(QObject, Extension):
             "materials_showcase":  AuthorsModel(self),
             "materials_available": PackagesModel(self),
             "materials_installed": PackagesModel(self)
-        }
+        } # type: Dict[str, ListModel]
 
         # These properties are for keeping track of the UI state:
         # ----------------------------------------------------------------------
         # View category defines which filter to use, and therefore effectively
         # which category is currently being displayed. For example, possible
         # values include "plugin" or "material", but also "installed".
-        self._view_category = "plugin"
+        self._view_category = "plugin" #type: str
 
         # View page defines which type of page layout to use. For example,
         # possible values include "overview", "detail" or "author".
-        self._view_page = "loading"
+        self._view_page = "loading" #type: str
 
         # Active package refers to which package is currently being downloaded,
         # installed, or otherwise modified.
-        self._active_package = None
+        self._active_package = None # type: Optional[Dict[str, Any]]
 
-        self._dialog = None
+        self._dialog = None #type: Optional[QObject]
-        self._restart_required = False
+        self._restart_required = False #type: bool
 
         # variables for the license agreement dialog
-        self._license_dialog_plugin_name = ""
+        self._license_dialog_plugin_name = "" #type: str
-        self._license_dialog_license_content = ""
+        self._license_dialog_license_content = "" #type: str
-        self._license_dialog_plugin_file_location = ""
+        self._license_dialog_plugin_file_location = "" #type: str
-        self._restart_dialog_message = ""
+        self._restart_dialog_message = "" #type: str
 
-        Application.getInstance().initializationFinished.connect(self._onAppInitialized)
+        self._application.initializationFinished.connect(self._onAppInitialized)
 
 
 
@@ -156,7 +152,8 @@ class Toolbox(QObject, Extension):
     # This is a plugin, so most of the components required are not ready when
     # this is initialized. Therefore, we wait until the application is ready.
     def _onAppInitialized(self) -> None:
-        self._package_manager = Application.getInstance().getPackageManager()
+        self._plugin_registry = self._application.getPluginRegistry()
+        self._package_manager = self._application.getPackageManager()
         self._sdk_version = self._getSDKVersion()
         self._cloud_api_version = self._getCloudAPIVersion()
         self._cloud_api_root = self._getCloudAPIRoot()
@@ -178,38 +175,38 @@ class Toolbox(QObject, Extension):
     def _getCloudAPIRoot(self) -> str:
         if not hasattr(cura, "CuraVersion"):
             return self.DEFAULT_CLOUD_API_ROOT
-        if not hasattr(cura.CuraVersion, "CuraCloudAPIRoot"):
+        if not hasattr(cura.CuraVersion, "CuraCloudAPIRoot"): # type: ignore
             return self.DEFAULT_CLOUD_API_ROOT
-        if not cura.CuraVersion.CuraCloudAPIRoot:
+        if not cura.CuraVersion.CuraCloudAPIRoot: # type: ignore
             return self.DEFAULT_CLOUD_API_ROOT
-        return cura.CuraVersion.CuraCloudAPIRoot
+        return cura.CuraVersion.CuraCloudAPIRoot # type: ignore
 
     # Get the cloud API version from CuraVersion
     def _getCloudAPIVersion(self) -> int:
         if not hasattr(cura, "CuraVersion"):
             return self.DEFAULT_CLOUD_API_VERSION
-        if not hasattr(cura.CuraVersion, "CuraCloudAPIVersion"):
+        if not hasattr(cura.CuraVersion, "CuraCloudAPIVersion"): # type: ignore
             return self.DEFAULT_CLOUD_API_VERSION
-        if not cura.CuraVersion.CuraCloudAPIVersion:
+        if not cura.CuraVersion.CuraCloudAPIVersion: # type: ignore
             return self.DEFAULT_CLOUD_API_VERSION
-        return cura.CuraVersion.CuraCloudAPIVersion
+        return cura.CuraVersion.CuraCloudAPIVersion # type: ignore
 
     # Get the packages version depending on Cura version settings.
     def _getSDKVersion(self) -> int:
         if not hasattr(cura, "CuraVersion"):
             return self._plugin_registry.APIVersion
-        if not hasattr(cura.CuraVersion, "CuraSDKVersion"):
+        if not hasattr(cura.CuraVersion, "CuraSDKVersion"): # type: ignore
             return self._plugin_registry.APIVersion
-        if not cura.CuraVersion.CuraSDKVersion:
+        if not cura.CuraVersion.CuraSDKVersion: # type: ignore
             return self._plugin_registry.APIVersion
-        return cura.CuraVersion.CuraSDKVersion
+        return cura.CuraVersion.CuraSDKVersion # type: ignore
 
     @pyqtSlot()
     def browsePackages(self) -> None:
         # Create the network manager:
         # This was formerly its own function but really had no reason to be as
         # it was never called more than once ever.
-        if self._network_manager:
+        if self._network_manager is not None:
             self._network_manager.finished.disconnect(self._onRequestFinished)
             self._network_manager.networkAccessibleChanged.disconnect(self._onNetworkAccessibleChanged)
         self._network_manager = QNetworkAccessManager()
@@ -235,11 +232,11 @@ class Toolbox(QObject, Extension):
     def _createDialog(self, qml_name: str) -> Optional[QObject]:
         Logger.log("d", "Toolbox: Creating dialog [%s].", qml_name)
         path = os.path.join(PluginRegistry.getInstance().getPluginPath(self.getPluginId()), "resources", "qml", qml_name)
-        dialog = Application.getInstance().createQmlComponent(path, {"toolbox": self})
+        dialog = self._application.createQmlComponent(path, {"toolbox": self})
         return dialog
 
 
-    def _convertPluginMetadata(self, plugin: dict) -> dict:
+    def _convertPluginMetadata(self, plugin: Dict[str, Any]) -> Dict[str, Any]:
         formatted = {
             "package_id": plugin["id"],
             "package_type": "plugin",
@@ -257,7 +254,6 @@ class Toolbox(QObject, Extension):
 
     @pyqtSlot()
     def _updateInstalledModels(self) -> None:
-
         # This is moved here to avoid code duplication and so that after installing plugins they get removed from the
         # list of old plugins
         old_plugin_ids = self._plugin_registry.getInstalledPlugins()
@@ -265,7 +261,7 @@ class Toolbox(QObject, Extension):
         scheduled_to_remove_package_ids = self._package_manager.getToRemovePackageIDs()
 
         self._old_plugin_ids = []
-        self._old_plugin_metadata = []
+        self._old_plugin_metadata = [] # type: List[Dict[str, Any]]
 
         for plugin_id in old_plugin_ids:
             # Neither the installed packages nor the packages that are scheduled to remove are old plugins
@@ -353,8 +349,8 @@ class Toolbox(QObject, Extension):
         return self._restart_required
 
     @pyqtSlot()
-    def restart(self):
+    def restart(self) -> None:
-        CuraApplication.getInstance().windowClosed()
+        self._application.windowClosed()
 
     def getRemotePackage(self, package_id: str) -> Optional[Dict]:
         # TODO: make the lookup in a dict, not a loop. canUpdate is called for every item.
@@ -432,7 +428,8 @@ class Toolbox(QObject, Extension):
         Logger.log("i", "Toolbox: Requesting %s metadata from server.", type)
         request = QNetworkRequest(self._request_urls[type])
         request.setRawHeader(*self._request_header)
-        self._network_manager.get(request)
+        if self._network_manager:
+            self._network_manager.get(request)
 
     @pyqtSlot(str)
     def startDownload(self, url: str) -> None:
@@ -441,15 +438,15 @@ class Toolbox(QObject, Extension):
         self._download_request = QNetworkRequest(url)
         if hasattr(QNetworkRequest, "FollowRedirectsAttribute"):
             # Patch for Qt 5.6-5.8
-            self._download_request.setAttribute(QNetworkRequest.FollowRedirectsAttribute, True)
+            cast(QNetworkRequest, self._download_request).setAttribute(QNetworkRequest.FollowRedirectsAttribute, True)
         if hasattr(QNetworkRequest, "RedirectPolicyAttribute"):
             # Patch for Qt 5.9+
-            self._download_request.setAttribute(QNetworkRequest.RedirectPolicyAttribute, True)
+            cast(QNetworkRequest, self._download_request).setAttribute(QNetworkRequest.RedirectPolicyAttribute, True)
-        self._download_request.setRawHeader(*self._request_header)
+        cast(QNetworkRequest, self._download_request).setRawHeader(*self._request_header)
-        self._download_reply = self._network_manager.get(self._download_request)
+        self._download_reply = cast(QNetworkAccessManager, self._network_manager).get(self._download_request)
         self.setDownloadProgress(0)
         self.setIsDownloading(True)
-        self._download_reply.downloadProgress.connect(self._onDownloadProgress)
+        cast(QNetworkReply, self._download_reply).downloadProgress.connect(self._onDownloadProgress)
 
     @pyqtSlot()
     def cancelDownload(self) -> None:
@@ -475,7 +472,6 @@ class Toolbox(QObject, Extension):
             self.resetDownload()
 
     def _onRequestFinished(self, reply: QNetworkReply) -> None:
-
         if reply.error() == QNetworkReply.TimeoutError:
             Logger.log("w", "Got a timeout.")
             self.setViewPage("errored")
@@ -551,12 +547,12 @@ class Toolbox(QObject, Extension):
             self.setDownloadProgress(new_progress)
             if bytes_sent == bytes_total:
                 self.setIsDownloading(False)
-                self._download_reply.downloadProgress.disconnect(self._onDownloadProgress)
+                cast(QNetworkReply, self._download_reply).downloadProgress.disconnect(self._onDownloadProgress)
                 # Must not delete the temporary file on Windows
                 self._temp_plugin_file = tempfile.NamedTemporaryFile(mode = "w+b", suffix = ".curapackage", delete = False)
                 file_path = self._temp_plugin_file.name
                 # Write first and close, otherwise on Windows, it cannot read the file
-                self._temp_plugin_file.write(self._download_reply.readAll())
+                self._temp_plugin_file.write(cast(QNetworkReply, self._download_reply).readAll())
                 self._temp_plugin_file.close()
                 self._onDownloadComplete(file_path)
 
@@ -577,13 +573,13 @@ class Toolbox(QObject, Extension):
 
     # Getter & Setters for Properties:
     # --------------------------------------------------------------------------
-    def setDownloadProgress(self, progress: Union[int, float]) -> None:
+    def setDownloadProgress(self, progress: float) -> None:
         if progress != self._download_progress:
             self._download_progress = progress
             self.onDownloadProgressChanged.emit()
 
     @pyqtProperty(int, fset = setDownloadProgress, notify = onDownloadProgressChanged)
-    def downloadProgress(self) -> int:
+    def downloadProgress(self) -> float:
         return self._download_progress
 
     def setIsDownloading(self, is_downloading: bool) -> None:

plugins/UM3NetworkPrinting/ClusterUM3OutputDevice.py

@@ -1,10 +1,12 @@
 # Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
 
+from typing import Any, cast, Set, Tuple, Union
+
+from UM.FileHandler.FileHandler import FileHandler
 from UM.FileHandler.FileWriter import FileWriter #To choose based on the output file mode (text vs. binary).
 from UM.FileHandler.WriteFileJob import WriteFileJob #To call the file writer asynchronously.
 from UM.Logger import Logger
-from UM.Application import Application
 from UM.Settings.ContainerRegistry import ContainerRegistry
 from UM.i18n import i18nCatalog
 from UM.Message import Message
@@ -13,6 +15,7 @@ from UM.OutputDevice import OutputDeviceError #To show that something went wrong
 from UM.Scene.SceneNode import SceneNode #For typing.
 from UM.Version import Version #To check against firmware versions for support.
 
+from cura.CuraApplication import CuraApplication
 from cura.PrinterOutput.NetworkedPrinterOutputDevice import NetworkedPrinterOutputDevice, AuthState
 from cura.PrinterOutput.PrinterOutputModel import PrinterOutputModel
 from cura.PrinterOutput.PrintJobOutputModel import PrintJobOutputModel
@@ -25,7 +28,7 @@ from PyQt5.QtNetwork import QNetworkRequest, QNetworkReply
 from PyQt5.QtGui import QDesktopServices
 from PyQt5.QtCore import pyqtSlot, QUrl, pyqtSignal, pyqtProperty, QObject
 
-from time import time, sleep
+from time import time
 from datetime import datetime
 from typing import Optional, Dict, List
 
@@ -44,15 +47,15 @@ class ClusterUM3OutputDevice(NetworkedPrinterOutputDevice):
     # Inheritance doesn't seem to work. Tying them together does work, but i'm open for better suggestions.
     clusterPrintersChanged = pyqtSignal()
 
-    def __init__(self, device_id, address, properties, parent = None):
+    def __init__(self, device_id, address, properties, parent = None) -> None:
         super().__init__(device_id = device_id, address = address, properties=properties, parent = parent)
         self._api_prefix = "/cluster-api/v1/"
 
         self._number_of_extruders = 2
 
-        self._dummy_lambdas = set()
+        self._dummy_lambdas = ("", {}, io.BytesIO()) #type: Tuple[str, Dict, Union[io.StringIO, io.BytesIO]]
 
-        self._print_jobs = []
+        self._print_jobs = [] # type: List[PrintJobOutputModel]
 
         self._monitor_view_qml_path = os.path.join(os.path.dirname(os.path.abspath(__file__)), "ClusterMonitorItem.qml")
         self._control_view_qml_path = os.path.join(os.path.dirname(os.path.abspath(__file__)), "ClusterControlItem.qml")
@@ -60,18 +63,18 @@ class ClusterUM3OutputDevice(NetworkedPrinterOutputDevice):
         # See comments about this hack with the clusterPrintersChanged signal
         self.printersChanged.connect(self.clusterPrintersChanged)
 
-        self._accepts_commands = True
+        self._accepts_commands = True #type: bool
 
         # Cluster does not have authentication, so default to authenticated
         self._authentication_state = AuthState.Authenticated
 
-        self._error_message = None
+        self._error_message = None #type: Optional[Message]
-        self._write_job_progress_message = None
+        self._write_job_progress_message = None #type: Optional[Message]
-        self._progress_message = None
+        self._progress_message = None #type: Optional[Message]
 
         self._active_printer = None  # type: Optional[PrinterOutputModel]
 
-        self._printer_selection_dialog = None
+        self._printer_selection_dialog = None #type: QObject
 
         self.setPriority(3)  # Make sure the output device gets selected above local file output
         self.setName(self._id)
@@ -80,25 +83,25 @@ class ClusterUM3OutputDevice(NetworkedPrinterOutputDevice):
 
         self.setConnectionText(i18n_catalog.i18nc("@info:status", "Connected over the network"))
 
-        self._printer_uuid_to_unique_name_mapping = {}
+        self._printer_uuid_to_unique_name_mapping = {}  # type: Dict[str, str]
 
-        self._finished_jobs = []
+        self._finished_jobs = [] # type: List[PrintJobOutputModel]
 
         self._cluster_size = int(properties.get(b"cluster_size", 0))
 
-        self._latest_reply_handler = None
+        self._latest_reply_handler = None #type: Optional[QNetworkReply]
 
-    def requestWrite(self, nodes: List[SceneNode], file_name=None, filter_by_machine=False, file_handler=None, **kwargs):
+    def requestWrite(self, nodes: List[SceneNode], file_name: Optional[str] = None, limit_mimetypes: bool = False, file_handler: Optional[FileHandler] = None, **kwargs: str) -> None:
         self.writeStarted.emit(self)
 
         #Formats supported by this application (file types that we can actually write).
         if file_handler:
             file_formats = file_handler.getSupportedFileTypesWrite()
         else:
-            file_formats = Application.getInstance().getMeshFileHandler().getSupportedFileTypesWrite()
+            file_formats = CuraApplication.getInstance().getMeshFileHandler().getSupportedFileTypesWrite()
 
         #Create a list from the supported file formats string.
-        machine_file_formats = Application.getInstance().getGlobalContainerStack().getMetaDataEntry("file_formats").split(";")
+        machine_file_formats = CuraApplication.getInstance().getGlobalContainerStack().getMetaDataEntry("file_formats").split(";")
         machine_file_formats = [file_type.strip() for file_type in machine_file_formats]
         #Exception for UM3 firmware version >=4.4: UFP is now supported and should be the preferred file format.
         if "application/x-ufp" not in machine_file_formats and self.printerType == "ultimaker3" and Version(self.firmwareVersion) >= Version("4.4"):
@@ -115,9 +118,9 @@ class ClusterUM3OutputDevice(NetworkedPrinterOutputDevice):
 
         #Just take the first file format available.
         if file_handler is not None:
-            writer = file_handler.getWriterByMimeType(preferred_format["mime_type"])
+            writer = file_handler.getWriterByMimeType(cast(str, preferred_format["mime_type"]))
         else:
-            writer = Application.getInstance().getMeshFileHandler().getWriterByMimeType(preferred_format["mime_type"])
+            writer = CuraApplication.getInstance().getMeshFileHandler().getWriterByMimeType(cast(str, preferred_format["mime_type"]))
 
         #This function pauses with the yield, waiting on instructions on which printer it needs to print with.
         self._sending_job = self._sendPrintJob(writer, preferred_format, nodes)
@@ -133,7 +136,7 @@ class ClusterUM3OutputDevice(NetworkedPrinterOutputDevice):
     def _spawnPrinterSelectionDialog(self):
         if self._printer_selection_dialog is None:
             path = os.path.join(os.path.dirname(os.path.abspath(__file__)), "PrintWindow.qml")
-            self._printer_selection_dialog = Application.getInstance().createQmlComponent(path, {"OutputDevice": self})
+            self._printer_selection_dialog = CuraApplication.getInstance().createQmlComponent(path, {"OutputDevice": self})
         if self._printer_selection_dialog is not None:
             self._printer_selection_dialog.show()
 
@@ -179,10 +182,10 @@ class ClusterUM3OutputDevice(NetworkedPrinterOutputDevice):
         target_printer = yield #Potentially wait on the user to select a target printer.
 
         # Using buffering greatly reduces the write time for many lines of gcode
+
+        stream = io.BytesIO() # type: Union[io.BytesIO, io.StringIO]# Binary mode.
         if preferred_format["mode"] == FileWriter.OutputMode.TextMode:
             stream = io.StringIO()
-        else: #Binary mode.
-            stream = io.BytesIO()
 
         job = WriteFileJob(writer, stream, nodes, preferred_format["mode"])
 
@@ -198,9 +201,7 @@ class ClusterUM3OutputDevice(NetworkedPrinterOutputDevice):
         yield True #Return that we had success!
         yield #To prevent having to catch the StopIteration exception.
 
-    from cura.Utils.Threading import call_on_qt_thread
+    def _sendPrintJobWaitOnWriteJobFinished(self, job: WriteFileJob) -> None:
-
-    def _sendPrintJobWaitOnWriteJobFinished(self, job):
         self._write_job_progress_message.hide()
 
         self._progress_message = Message(i18n_catalog.i18nc("@info:status", "Sending data to printer"), lifetime = 0, dismissable = False, progress = -1,
@@ -221,40 +222,41 @@ class ClusterUM3OutputDevice(NetworkedPrinterOutputDevice):
         # Add user name to the print_job
         parts.append(self._createFormPart("name=owner", bytes(self._getUserName(), "utf-8"), "text/plain"))
 
-        file_name = Application.getInstance().getPrintInformation().jobName + "." + preferred_format["extension"]
+        file_name = CuraApplication.getInstance().getPrintInformation().jobName + "." + preferred_format["extension"]
 
         output = stream.getvalue() #Either str or bytes depending on the output mode.
         if isinstance(stream, io.StringIO):
-            output = output.encode("utf-8")
+            output = cast(str, output).encode("utf-8")
+        output = cast(bytes, output)
 
         parts.append(self._createFormPart("name=\"file\"; filename=\"%s\"" % file_name, output))
 
-        self._latest_reply_handler = self.postFormWithParts("print_jobs/", parts, onFinished=self._onPostPrintJobFinished, onProgress=self._onUploadPrintJobProgress)
+        self._latest_reply_handler = self.postFormWithParts("print_jobs/", parts, on_finished = self._onPostPrintJobFinished, on_progress = self._onUploadPrintJobProgress)
 
-    @pyqtProperty(QObject, notify=activePrinterChanged)
+    @pyqtProperty(QObject, notify = activePrinterChanged)
     def activePrinter(self) -> Optional[PrinterOutputModel]:
         return self._active_printer
 
     @pyqtSlot(QObject)
-    def setActivePrinter(self, printer: Optional[PrinterOutputModel]):
+    def setActivePrinter(self, printer: Optional[PrinterOutputModel]) -> None:
         if self._active_printer != printer:
             if self._active_printer and self._active_printer.camera:
                 self._active_printer.camera.stop()
             self._active_printer = printer
             self.activePrinterChanged.emit()
 
-    def _onPostPrintJobFinished(self, reply):
+    def _onPostPrintJobFinished(self, reply: QNetworkReply) -> None:
         self._progress_message.hide()
         self._compressing_gcode = False
         self._sending_gcode = False
 
-    def _onUploadPrintJobProgress(self, bytes_sent:int, bytes_total:int):
+    def _onUploadPrintJobProgress(self, bytes_sent: int, bytes_total: int) -> None:
         if bytes_total > 0:
             new_progress = bytes_sent / bytes_total * 100
             # Treat upload progress as response. Uploading can take more than 10 seconds, so if we don't, we can get
             # timeout responses if this happens.
             self._last_response_time = time()
-            if new_progress > self._progress_message.getProgress():
+            if self._progress_message and new_progress > self._progress_message.getProgress():
                 self._progress_message.show()  # Ensure that the message is visible.
                 self._progress_message.setProgress(bytes_sent / bytes_total * 100)
 
@@ -271,16 +273,18 @@ class ClusterUM3OutputDevice(NetworkedPrinterOutputDevice):
                 self._success_message.actionTriggered.connect(self._successMessageActionTriggered)
                 self._success_message.show()
         else:
-            self._progress_message.setProgress(0)
+            if self._progress_message is not None:
-            self._progress_message.hide()
+                self._progress_message.setProgress(0)
+                self._progress_message.hide()
 
-    def _progressMessageActionTriggered(self, message_id: Optional[str]=None, action_id: Optional[str]=None) -> None:
+    def _progressMessageActionTriggered(self, message_id: Optional[str] = None, action_id: Optional[str] = None) -> None:
         if action_id == "Abort":
             Logger.log("d", "User aborted sending print to remote.")
-            self._progress_message.hide()
+            if self._progress_message is not None:
+                self._progress_message.hide()
             self._compressing_gcode = False
             self._sending_gcode = False
-            Application.getInstance().getController().setActiveStage("PrepareStage")
+            CuraApplication.getInstance().getController().setActiveStage("PrepareStage")
 
             # After compressing the sliced model Cura sends data to printer, to stop receiving updates from the request
             # the "reply" should be disconnected
@@ -288,9 +292,9 @@ class ClusterUM3OutputDevice(NetworkedPrinterOutputDevice):
                 self._latest_reply_handler.disconnect()
                 self._latest_reply_handler = None
 
-    def _successMessageActionTriggered(self, message_id: Optional[str]=None, action_id: Optional[str]=None) -> None:
+    def _successMessageActionTriggered(self, message_id: Optional[str] = None, action_id: Optional[str] = None) -> None:
         if action_id == "View":
-            Application.getInstance().getController().setActiveStage("MonitorStage")
+            CuraApplication.getInstance().getController().setActiveStage("MonitorStage")
 
     @pyqtSlot()
     def openPrintJobControlPanel(self) -> None:
@@ -302,21 +306,21 @@ class ClusterUM3OutputDevice(NetworkedPrinterOutputDevice):
         Logger.log("d", "Opening printer control panel...")
         QDesktopServices.openUrl(QUrl("http://" + self._address + "/printers"))
 
-    @pyqtProperty("QVariantList", notify=printJobsChanged)
+    @pyqtProperty("QVariantList", notify = printJobsChanged)
-    def printJobs(self)-> List[PrintJobOutputModel] :
+    def printJobs(self)-> List[PrintJobOutputModel]:
         return self._print_jobs
 
-    @pyqtProperty("QVariantList", notify=printJobsChanged)
+    @pyqtProperty("QVariantList", notify = printJobsChanged)
     def queuedPrintJobs(self) -> List[PrintJobOutputModel]:
         return [print_job for print_job in self._print_jobs if print_job.state == "queued"]
 
-    @pyqtProperty("QVariantList", notify=printJobsChanged)
+    @pyqtProperty("QVariantList", notify = printJobsChanged)
     def activePrintJobs(self) -> List[PrintJobOutputModel]:
         return [print_job for print_job in self._print_jobs if print_job.assignedPrinter is not None and print_job.state != "queued"]
 
-    @pyqtProperty("QVariantList", notify=clusterPrintersChanged)
+    @pyqtProperty("QVariantList", notify = clusterPrintersChanged)
-    def connectedPrintersTypeCount(self) -> List[PrinterOutputModel]:
+    def connectedPrintersTypeCount(self) -> List[Dict[str, str]]:
-        printer_count = {}
+        printer_count = {} # type: Dict[str, int]
         for printer in self._printers:
             if printer.type in printer_count:
                 printer_count[printer.type] += 1
@@ -324,20 +328,20 @@ class ClusterUM3OutputDevice(NetworkedPrinterOutputDevice):
                 printer_count[printer.type] = 1
         result = []
         for machine_type in printer_count:
-            result.append({"machine_type": machine_type, "count": printer_count[machine_type]})
+            result.append({"machine_type": machine_type, "count": str(printer_count[machine_type])})
         return result
 
-    @pyqtSlot(int, result=str)
+    @pyqtSlot(int, result = str)
     def formatDuration(self, seconds: int) -> str:
         return Duration(seconds).getDisplayString(DurationFormat.Format.Short)
 
-    @pyqtSlot(int, result=str)
+    @pyqtSlot(int, result = str)
     def getTimeCompleted(self, time_remaining: int) -> str:
         current_time = time()
         datetime_completed = datetime.fromtimestamp(current_time + time_remaining)
         return "{hour:02d}:{minute:02d}".format(hour=datetime_completed.hour, minute=datetime_completed.minute)
 
-    @pyqtSlot(int, result=str)
+    @pyqtSlot(int, result = str)
     def getDateCompleted(self, time_remaining: int) -> str:
         current_time = time()
         datetime_completed = datetime.fromtimestamp(current_time + time_remaining)
@@ -367,10 +371,9 @@ class ClusterUM3OutputDevice(NetworkedPrinterOutputDevice):
         self._finished_jobs = finished_jobs
 
     def _update(self) -> None:
-        if not super()._update():
+        super()._update()
-            return
+        self.get("printers/", on_finished = self._onGetPrintersDataFinished)
-        self.get("printers/", onFinished=self._onGetPrintersDataFinished)
+        self.get("print_jobs/", on_finished = self._onGetPrintJobsFinished)
-        self.get("print_jobs/", onFinished=self._onGetPrintJobsFinished)
 
     def _onGetPrintJobsFinished(self, reply: QNetworkReply) -> None:
         if not checkValidGetReply(reply):
@@ -409,7 +412,7 @@ class ClusterUM3OutputDevice(NetworkedPrinterOutputDevice):
         removed_jobs = [print_job for print_job in self._print_jobs if print_job not in print_jobs_seen]
 
         for removed_job in removed_jobs:
-            job_list_changed |= self._removeJob(removed_job)
+            job_list_changed = job_list_changed or self._removeJob(removed_job)
 
         if job_list_changed:
             self.printJobsChanged.emit()  # Do a single emit for all print job changes.
@@ -443,27 +446,27 @@ class ClusterUM3OutputDevice(NetworkedPrinterOutputDevice):
         if removed_printers or printer_list_changed:
             self.printersChanged.emit()
 
-    def _createPrinterModel(self, data: Dict) -> PrinterOutputModel:
+    def _createPrinterModel(self, data: Dict[str, Any]) -> PrinterOutputModel:
-        printer = PrinterOutputModel(output_controller=ClusterUM3PrinterOutputController(self),
+        printer = PrinterOutputModel(output_controller = ClusterUM3PrinterOutputController(self),
-                                     number_of_extruders=self._number_of_extruders)
+                                     number_of_extruders = self._number_of_extruders)
         printer.setCamera(NetworkCamera("http://" + data["ip_address"] + ":8080/?action=stream"))
         self._printers.append(printer)
         return printer
 
-    def _createPrintJobModel(self, data: Dict) -> PrintJobOutputModel:
+    def _createPrintJobModel(self, data: Dict[str, Any]) -> PrintJobOutputModel:
         print_job = PrintJobOutputModel(output_controller=ClusterUM3PrinterOutputController(self),
                                         key=data["uuid"], name= data["name"])
         print_job.stateChanged.connect(self._printJobStateChanged)
         self._print_jobs.append(print_job)
         return print_job
 
-    def _updatePrintJob(self, print_job: PrintJobOutputModel, data: Dict) -> None:
+    def _updatePrintJob(self, print_job: PrintJobOutputModel, data: Dict[str, Any]) -> None:
         print_job.updateTimeTotal(data["time_total"])
         print_job.updateTimeElapsed(data["time_elapsed"])
         print_job.updateState(data["status"])
         print_job.updateOwner(data["owner"])
 
-    def _updatePrinter(self, printer: PrinterOutputModel, data: Dict) -> None:
+    def _updatePrinter(self, printer: PrinterOutputModel, data: Dict[str, Any]) -> None:
         # For some unknown reason the cluster wants UUID for everything, except for sending a job directly to a printer.
         # Then we suddenly need the unique name. So in order to not have to mess up all the other code, we save a mapping.
         self._printer_uuid_to_unique_name_mapping[data["uuid"]] = data["unique_name"]
@@ -479,7 +482,7 @@ class ClusterUM3OutputDevice(NetworkedPrinterOutputDevice):
         printer.updateKey(data["uuid"])
         printer.updateType(data["machine_variant"])
 
-        # Do not store the buildplate information that comes from connect if the current printer has not buildplate information
+        # Do not store the build plate information that comes from connect if the current printer has not build plate information
         if "build_plate" in data and machine_definition.getMetaDataEntry("has_variant_buildplates", False):
             printer.updateBuildplateName(data["build_plate"]["type"])
         if not data["enabled"]:
@@ -518,7 +521,7 @@ class ClusterUM3OutputDevice(NetworkedPrinterOutputDevice):
                                                brand=brand, color=color, name=name)
                 extruder.updateActiveMaterial(material)
 
-    def _removeJob(self, job: PrintJobOutputModel):
+    def _removeJob(self, job: PrintJobOutputModel) -> bool:
         if job not in self._print_jobs:
             return False
 
@@ -529,23 +532,23 @@ class ClusterUM3OutputDevice(NetworkedPrinterOutputDevice):
 
         return True
 
-    def _removePrinter(self, printer: PrinterOutputModel):
+    def _removePrinter(self, printer: PrinterOutputModel) -> None:
         self._printers.remove(printer)
         if self._active_printer == printer:
             self._active_printer = None
             self.activePrinterChanged.emit()
 
 
-def loadJsonFromReply(reply):
+def loadJsonFromReply(reply: QNetworkReply) -> Optional[List[Dict[str, Any]]]:
     try:
         result = json.loads(bytes(reply.readAll()).decode("utf-8"))
     except json.decoder.JSONDecodeError:
         Logger.logException("w", "Unable to decode JSON from reply.")
-        return
+        return None
     return result
 
 
-def checkValidGetReply(reply):
+def checkValidGetReply(reply: QNetworkReply) -> bool:
     status_code = reply.attribute(QNetworkRequest.HttpStatusCodeAttribute)
 
     if status_code != 200:
@@ -554,7 +557,8 @@ def checkValidGetReply(reply):
     return True
 
 
-def findByKey(list, key):
+def findByKey(list: List[Union[PrintJobOutputModel, PrinterOutputModel]], key: str) -> Optional[PrintJobOutputModel]:
     for item in list:
         if item.key == key:
-            return item
+            return item
+    return None

plugins/UM3NetworkPrinting/DiscoverUM3Action.py

@@ -1,43 +1,47 @@
+# Copyright (c) 2018 Ultimaker B.V.
+# Cura is released under the terms of the LGPLv3 or higher.
+
 import os.path
 import time
+from typing import Optional
 
 from PyQt5.QtCore import pyqtSignal, pyqtProperty, pyqtSlot, QObject
 
-from UM.Application import Application
 from UM.PluginRegistry import PluginRegistry
 from UM.Logger import Logger
 from UM.i18n import i18nCatalog
 
+from cura.CuraApplication import CuraApplication
 from cura.MachineAction import MachineAction
 
+from .UM3OutputDevicePlugin import UM3OutputDevicePlugin
+
 catalog = i18nCatalog("cura")
 
 
 class DiscoverUM3Action(MachineAction):
     discoveredDevicesChanged = pyqtSignal()
 
-    def __init__(self):
+    def __init__(self) -> None:
         super().__init__("DiscoverUM3Action", catalog.i18nc("@action","Connect via Network"))
         self._qml_url = "DiscoverUM3Action.qml"
 
-        self._network_plugin = None
+        self._network_plugin = None #type: Optional[UM3OutputDevicePlugin]
 
-        self.__additional_components_context = None
+        self.__additional_components_view = None #type: Optional[QObject]
-        self.__additional_component = None
-        self.__additional_components_view = None
 
-        Application.getInstance().engineCreatedSignal.connect(self._createAdditionalComponentsView)
+        CuraApplication.getInstance().engineCreatedSignal.connect(self._createAdditionalComponentsView)
 
-        self._last_zero_conf_event_time = time.time()
+        self._last_zero_conf_event_time = time.time() #type: float
 
         # Time to wait after a zero-conf service change before allowing a zeroconf reset
-        self._zero_conf_change_grace_period = 0.25
+        self._zero_conf_change_grace_period = 0.25 #type: float
 
     @pyqtSlot()
     def startDiscovery(self):
         if not self._network_plugin:
             Logger.log("d", "Starting device discovery.")
-            self._network_plugin = Application.getInstance().getOutputDeviceManager().getOutputDevicePlugin("UM3NetworkPrinting")
+            self._network_plugin = CuraApplication.getInstance().getOutputDeviceManager().getOutputDevicePlugin("UM3NetworkPrinting")
             self._network_plugin.discoveredDevicesChanged.connect(self._onDeviceDiscoveryChanged)
             self.discoveredDevicesChanged.emit()
 
@@ -93,16 +97,16 @@ class DiscoverUM3Action(MachineAction):
             return []
 
     @pyqtSlot(str)
-    def setGroupName(self, group_name):
+    def setGroupName(self, group_name: str) -> None:
         Logger.log("d", "Attempting to set the group name of the active machine to %s", group_name)
-        global_container_stack = Application.getInstance().getGlobalContainerStack()
+        global_container_stack = CuraApplication.getInstance().getGlobalContainerStack()
         if global_container_stack:
             meta_data = global_container_stack.getMetaData()
             if "connect_group_name" in meta_data:
                 previous_connect_group_name = meta_data["connect_group_name"]
                 global_container_stack.setMetaDataEntry("connect_group_name", group_name)
                 # Find all the places where there is the same group name and change it accordingly
-                Application.getInstance().getMachineManager().replaceContainersMetadata(key = "connect_group_name", value = previous_connect_group_name, new_value = group_name)
+                CuraApplication.getInstance().getMachineManager().replaceContainersMetadata(key = "connect_group_name", value = previous_connect_group_name, new_value = group_name)
             else:
                 global_container_stack.addMetaDataEntry("connect_group_name", group_name)
                 global_container_stack.addMetaDataEntry("hidden", False)
@@ -112,9 +116,9 @@ class DiscoverUM3Action(MachineAction):
             self._network_plugin.reCheckConnections()
 
     @pyqtSlot(str)
-    def setKey(self, key):
+    def setKey(self, key: str) -> None:
         Logger.log("d", "Attempting to set the network key of the active machine to %s", key)
-        global_container_stack = Application.getInstance().getGlobalContainerStack()
+        global_container_stack = CuraApplication.getInstance().getGlobalContainerStack()
         if global_container_stack:
             meta_data = global_container_stack.getMetaData()
             if "um_network_key" in meta_data:
@@ -124,7 +128,7 @@ class DiscoverUM3Action(MachineAction):
                 Logger.log("d", "Removing old authentication id %s for device %s", global_container_stack.getMetaDataEntry("network_authentication_id", None), key)
                 global_container_stack.removeMetaDataEntry("network_authentication_id")
                 global_container_stack.removeMetaDataEntry("network_authentication_key")
-                Application.getInstance().getMachineManager().replaceContainersMetadata(key = "um_network_key", value = previous_network_key, new_value = key)
+                CuraApplication.getInstance().getMachineManager().replaceContainersMetadata(key = "um_network_key", value = previous_network_key, new_value = key)
             else:
                 global_container_stack.addMetaDataEntry("um_network_key", key)
 
@@ -134,7 +138,7 @@ class DiscoverUM3Action(MachineAction):
 
     @pyqtSlot(result = str)
     def getStoredKey(self) -> str:
-        global_container_stack = Application.getInstance().getGlobalContainerStack()
+        global_container_stack = CuraApplication.getInstance().getGlobalContainerStack()
         if global_container_stack:
             meta_data = global_container_stack.getMetaData()
             if "um_network_key" in meta_data:
@@ -149,12 +153,12 @@ class DiscoverUM3Action(MachineAction):
         return ""
 
     @pyqtSlot(str, result = bool)
-    def existsKey(self, key) -> bool:
+    def existsKey(self, key: str) -> bool:
-        return Application.getInstance().getMachineManager().existNetworkInstances(network_key = key)
+        return CuraApplication.getInstance().getMachineManager().existNetworkInstances(network_key = key)
 
     @pyqtSlot()
-    def loadConfigurationFromPrinter(self):
+    def loadConfigurationFromPrinter(self) -> None:
-        machine_manager = Application.getInstance().getMachineManager()
+        machine_manager = CuraApplication.getInstance().getMachineManager()
         hotend_ids = machine_manager.printerOutputDevices[0].hotendIds
         for index in range(len(hotend_ids)):
             machine_manager.printerOutputDevices[0].hotendIdChanged.emit(index, hotend_ids[index])
@@ -162,16 +166,16 @@ class DiscoverUM3Action(MachineAction):
         for index in range(len(material_ids)):
             machine_manager.printerOutputDevices[0].materialIdChanged.emit(index, material_ids[index])
 
-    def _createAdditionalComponentsView(self):
+    def _createAdditionalComponentsView(self) -> None:
         Logger.log("d", "Creating additional ui components for UM3.")
 
         # Create networking dialog
         path = os.path.join(PluginRegistry.getInstance().getPluginPath("UM3NetworkPrinting"), "UM3InfoComponents.qml")
-        self.__additional_components_view = Application.getInstance().createQmlComponent(path, {"manager": self})
+        self.__additional_components_view = CuraApplication.getInstance().createQmlComponent(path, {"manager": self})
         if not self.__additional_components_view:
             Logger.log("w", "Could not create ui components for UM3.")
             return
 
         # Create extra components
-        Application.getInstance().addAdditionalComponent("monitorButtons", self.__additional_components_view.findChild(QObject, "networkPrinterConnectButton"))
+        CuraApplication.getInstance().addAdditionalComponent("monitorButtons", self.__additional_components_view.findChild(QObject, "networkPrinterConnectButton"))
-        Application.getInstance().addAdditionalComponent("machinesDetailPane", self.__additional_components_view.findChild(QObject, "networkPrinterConnectionInfo"))
+        CuraApplication.getInstance().addAdditionalComponent("machinesDetailPane", self.__additional_components_view.findChild(QObject, "networkPrinterConnectionInfo"))

plugins/UM3NetworkPrinting/LegacyUM3OutputDevice.py

@@ -1,3 +1,8 @@
+from typing import List, Optional
+
+from UM.FileHandler.FileHandler import FileHandler
+from UM.Scene.SceneNode import SceneNode
+from cura.CuraApplication import CuraApplication
 from cura.PrinterOutput.NetworkedPrinterOutputDevice import NetworkedPrinterOutputDevice, AuthState
 from cura.PrinterOutput.PrinterOutputModel import PrinterOutputModel
 from cura.PrinterOutput.PrintJobOutputModel import PrintJobOutputModel
@@ -9,12 +14,11 @@ from cura.Settings.ExtruderManager import ExtruderManager
 
 from UM.Logger import Logger
 from UM.Settings.ContainerRegistry import ContainerRegistry
-from UM.Application import Application
 from UM.i18n import i18nCatalog
 from UM.Message import Message
 
 from PyQt5.QtNetwork import QNetworkRequest
-from PyQt5.QtCore import QTimer, QCoreApplication
+from PyQt5.QtCore import QTimer
 from PyQt5.QtWidgets import QMessageBox
 
 from .LegacyUM3PrinterOutputController import LegacyUM3PrinterOutputController
@@ -39,7 +43,7 @@ i18n_catalog = i18nCatalog("cura")
 #   4. At this point the machine either has the state Authenticated or AuthenticationDenied.
 #   5. As a final step, we verify the authentication, as this forces the QT manager to setup the authenticator.
 class LegacyUM3OutputDevice(NetworkedPrinterOutputDevice):
-    def __init__(self, device_id, address: str, properties, parent = None):
+    def __init__(self, device_id, address: str, properties, parent = None) -> None:
         super().__init__(device_id = device_id, address = address, properties = properties, parent = parent)
         self._api_prefix = "/api/v1/"
         self._number_of_extruders = 2
@@ -125,7 +129,7 @@ class LegacyUM3OutputDevice(NetworkedPrinterOutputDevice):
     def connect(self):
         super().connect()
         self._setupMessages()
-        global_container = Application.getInstance().getGlobalContainerStack()
+        global_container = CuraApplication.getInstance().getGlobalContainerStack()
         if global_container:
             self._authentication_id = global_container.getMetaDataEntry("network_authentication_id", None)
             self._authentication_key = global_container.getMetaDataEntry("network_authentication_key", None)
@@ -168,7 +172,7 @@ class LegacyUM3OutputDevice(NetworkedPrinterOutputDevice):
                 # NotImplementedError. We can simply ignore these.
                 pass
 
-    def requestWrite(self, nodes, file_name=None, filter_by_machine=False, file_handler=None, **kwargs):
+    def requestWrite(self, nodes: List[SceneNode], file_name: Optional[str] = None, limit_mimetypes: bool = False, file_handler: Optional[FileHandler] = None, **kwargs: str) -> None:
         if not self.activePrinter:
             # No active printer. Unable to write
             return
@@ -183,8 +187,8 @@ class LegacyUM3OutputDevice(NetworkedPrinterOutputDevice):
 
         self.writeStarted.emit(self)
 
-        gcode_dict = getattr(Application.getInstance().getController().getScene(), "gcode_dict", [])
+        gcode_dict = getattr(CuraApplication.getInstance().getController().getScene(), "gcode_dict", [])
-        active_build_plate_id = Application.getInstance().getMultiBuildPlateModel().activeBuildPlate
+        active_build_plate_id = CuraApplication.getInstance().getMultiBuildPlateModel().activeBuildPlate
         gcode_list = gcode_dict[active_build_plate_id]
 
         if not gcode_list:
@@ -203,7 +207,7 @@ class LegacyUM3OutputDevice(NetworkedPrinterOutputDevice):
             for error in errors:
                 detailed_text += error + "\n"
 
-            Application.getInstance().messageBox(i18n_catalog.i18nc("@window:title", "Mismatched configuration"),
+            CuraApplication.getInstance().messageBox(i18n_catalog.i18nc("@window:title", "Mismatched configuration"),
                                                  text,
                                                  informative_text,
                                                  detailed_text,
@@ -225,7 +229,7 @@ class LegacyUM3OutputDevice(NetworkedPrinterOutputDevice):
             for warning in warnings:
                 detailed_text += warning + "\n"
 
-            Application.getInstance().messageBox(i18n_catalog.i18nc("@window:title", "Mismatched configuration"),
+            CuraApplication.getInstance().messageBox(i18n_catalog.i18nc("@window:title", "Mismatched configuration"),
                                                  text,
                                                  informative_text,
                                                  detailed_text,
@@ -239,7 +243,7 @@ class LegacyUM3OutputDevice(NetworkedPrinterOutputDevice):
         self._startPrint()
 
         # Notify the UI that a switch to the print monitor should happen
-        Application.getInstance().getController().setActiveStage("MonitorStage")
+        CuraApplication.getInstance().getController().setActiveStage("MonitorStage")
 
     def _startPrint(self):
         Logger.log("i", "Sending print job to printer.")
@@ -264,7 +268,7 @@ class LegacyUM3OutputDevice(NetworkedPrinterOutputDevice):
             # Abort was called.
             return
 
-        file_name = "%s.gcode.gz" % Application.getInstance().getPrintInformation().jobName
+        file_name = "%s.gcode.gz" % CuraApplication.getInstance().getPrintInformation().jobName
         self.postForm("print_job", "form-data; name=\"file\";filename=\"%s\"" % file_name, compressed_gcode,
                       onFinished=self._onPostPrintJobFinished)
 
@@ -276,7 +280,7 @@ class LegacyUM3OutputDevice(NetworkedPrinterOutputDevice):
             self._progress_message.hide()
             self._compressing_gcode = False
             self._sending_gcode = False
-            Application.getInstance().getController().setActiveStage("PrepareStage")
+            CuraApplication.getInstance().getController().setActiveStage("PrepareStage")
 
     def _onPostPrintJobFinished(self, reply):
         self._progress_message.hide()
@@ -301,7 +305,7 @@ class LegacyUM3OutputDevice(NetworkedPrinterOutputDevice):
             if button == QMessageBox.Yes:
                 self._startPrint()
             else:
-                Application.getInstance().getController().setActiveStage("PrepareStage")
+                CuraApplication.getInstance().getController().setActiveStage("PrepareStage")
                 # For some unknown reason Cura on OSX will hang if we do the call back code
                 # immediately without first returning and leaving QML's event system.
 
@@ -309,7 +313,7 @@ class LegacyUM3OutputDevice(NetworkedPrinterOutputDevice):
 
     def _checkForErrors(self):
         errors = []
-        print_information = Application.getInstance().getPrintInformation()
+        print_information = CuraApplication.getInstance().getPrintInformation()
         if not print_information.materialLengths:
             Logger.log("w", "There is no material length information. Unable to check for errors.")
             return errors
@@ -329,7 +333,7 @@ class LegacyUM3OutputDevice(NetworkedPrinterOutputDevice):
 
     def _checkForWarnings(self):
         warnings = []
-        print_information = Application.getInstance().getPrintInformation()
+        print_information = CuraApplication.getInstance().getPrintInformation()
 
         if not print_information.materialLengths:
             Logger.log("w", "There is no material length information. Unable to check for warnings.")
@@ -452,7 +456,7 @@ class LegacyUM3OutputDevice(NetworkedPrinterOutputDevice):
             self._authentication_failed_message.show()
 
     def _saveAuthentication(self):
-        global_container_stack = Application.getInstance().getGlobalContainerStack()
+        global_container_stack = CuraApplication.getInstance().getGlobalContainerStack()
         if global_container_stack:
             if "network_authentication_key" in global_container_stack.getMetaData():
                 global_container_stack.setMetaDataEntry("network_authentication_key", self._authentication_key)
@@ -465,7 +469,7 @@ class LegacyUM3OutputDevice(NetworkedPrinterOutputDevice):
                 global_container_stack.addMetaDataEntry("network_authentication_id", self._authentication_id)
 
             # Force save so we are sure the data is not lost.
-            Application.getInstance().saveStack(global_container_stack)
+            CuraApplication.getInstance().saveStack(global_container_stack)
             Logger.log("i", "Authentication succeeded for id %s and key %s", self._authentication_id,
                        self._getSafeAuthKey())
         else:
@@ -496,7 +500,7 @@ class LegacyUM3OutputDevice(NetworkedPrinterOutputDevice):
         self._authentication_id = None
 
         self.post("auth/request",
-                  json.dumps({"application":  "Cura-" + Application.getInstance().getVersion(),
+                  json.dumps({"application":  "Cura-" + CuraApplication.getInstance().getVersion(),
                                                "user": self._getUserName()}).encode(),
                   onFinished=self._onRequestAuthenticationFinished)
 
@@ -542,7 +546,7 @@ class LegacyUM3OutputDevice(NetworkedPrinterOutputDevice):
                        "Got status code {status_code} while trying to get printer data".format(status_code=status_code))
 
     def materialHotendChangedMessage(self, callback):
-        Application.getInstance().messageBox(i18n_catalog.i18nc("@window:title", "Sync with your printer"),
+        CuraApplication.getInstance().messageBox(i18n_catalog.i18nc("@window:title", "Sync with your printer"),
                                              i18n_catalog.i18nc("@label",
                                                                 "Would you like to use your current printer configuration in Cura?"),
                                              i18n_catalog.i18nc("@label",

plugins/USBPrinting/USBPrinterOutputDevice.py

@@ -3,10 +3,10 @@
 
 from UM.Logger import Logger
 from UM.i18n import i18nCatalog
-from UM.Application import Application
 from UM.Qt.Duration import DurationFormat
 from UM.PluginRegistry import PluginRegistry
 
+from cura.CuraApplication import CuraApplication
 from cura.PrinterOutputDevice import PrinterOutputDevice, ConnectionState
 from cura.PrinterOutput.PrinterOutputModel import PrinterOutputModel
 from cura.PrinterOutput.PrintJobOutputModel import PrintJobOutputModel
@@ -22,7 +22,7 @@ from threading import Thread, Event
 from time import time, sleep
 from queue import Queue
 from enum import IntEnum
-from typing import Union, Optional, List
+from typing import Union, Optional, List, cast
 
 import re
 import functools  # Used for reduce
@@ -35,7 +35,7 @@ class USBPrinterOutputDevice(PrinterOutputDevice):
     firmwareProgressChanged = pyqtSignal()
     firmwareUpdateStateChanged = pyqtSignal()
 
-    def __init__(self, serial_port: str, baud_rate: Optional[int] = None):
+    def __init__(self, serial_port: str, baud_rate: Optional[int] = None) -> None:
         super().__init__(serial_port)
         self.setName(catalog.i18nc("@item:inmenu", "USB printing"))
         self.setShortDescription(catalog.i18nc("@action:button Preceded by 'Ready to'.", "Print via USB"))
@@ -68,7 +68,7 @@ class USBPrinterOutputDevice(PrinterOutputDevice):
         self._is_printing = False  # A print is being sent.
 
         ## Set when print is started in order to check running time.
-        self._print_start_time = None  # type: Optional[int]
+        self._print_start_time = None  # type: Optional[float]
         self._print_estimated_time = None  # type: Optional[int]
 
         self._accepts_commands = True
@@ -83,7 +83,7 @@ class USBPrinterOutputDevice(PrinterOutputDevice):
         self.setConnectionText(catalog.i18nc("@info:status", "Connected via USB"))
 
         # Queue for commands that need to be sent.
-        self._command_queue = Queue()
+        self._command_queue = Queue()   # type: Queue
         # Event to indicate that an "ok" was received from the printer after sending a command.
         self._command_received = Event()
         self._command_received.set()
@@ -107,11 +107,11 @@ class USBPrinterOutputDevice(PrinterOutputDevice):
         # cancel any ongoing preheat timer before starting a print
         self._printers[0].getController().stopPreheatTimers()
 
-        Application.getInstance().getController().setActiveStage("MonitorStage")
+        CuraApplication.getInstance().getController().setActiveStage("MonitorStage")
 
         # find the G-code for the active build plate to print
-        active_build_plate_id = Application.getInstance().getMultiBuildPlateModel().activeBuildPlate
+        active_build_plate_id = CuraApplication.getInstance().getMultiBuildPlateModel().activeBuildPlate
-        gcode_dict = getattr(Application.getInstance().getController().getScene(), "gcode_dict")
+        gcode_dict = getattr(CuraApplication.getInstance().getController().getScene(), "gcode_dict")
         gcode_list = gcode_dict[active_build_plate_id]
 
         self._printGCode(gcode_list)
@@ -121,7 +121,7 @@ class USBPrinterOutputDevice(PrinterOutputDevice):
     def showFirmwareInterface(self):
         if self._firmware_view is None:
             path = os.path.join(PluginRegistry.getInstance().getPluginPath("USBPrinting"), "FirmwareUpdateWindow.qml")
-            self._firmware_view = Application.getInstance().createQmlComponent(path, {"manager": self})
+            self._firmware_view = CuraApplication.getInstance().createQmlComponent(path, {"manager": self})
 
         self._firmware_view.show()
 
@@ -180,7 +180,7 @@ class USBPrinterOutputDevice(PrinterOutputDevice):
         self.setFirmwareUpdateState(FirmwareUpdateState.completed)
 
         # Try to re-connect with the machine again, which must be done on the Qt thread, so we use call later.
-        Application.getInstance().callLater(self.connect)
+        CuraApplication.getInstance().callLater(self.connect)
 
     @pyqtProperty(float, notify = firmwareProgressChanged)
     def firmwareProgress(self):
@@ -214,7 +214,7 @@ class USBPrinterOutputDevice(PrinterOutputDevice):
         self._gcode_position = 0
         self._print_start_time = time()
 
-        self._print_estimated_time = int(Application.getInstance().getPrintInformation().currentPrintTime.getDisplayString(DurationFormat.Format.Seconds))
+        self._print_estimated_time = int(CuraApplication.getInstance().getPrintInformation().currentPrintTime.getDisplayString(DurationFormat.Format.Seconds))
 
         for i in range(0, 4):  # Push first 4 entries before accepting other inputs
             self._sendNextGcodeLine()
@@ -250,7 +250,7 @@ class USBPrinterOutputDevice(PrinterOutputDevice):
             except SerialException:
                 Logger.log("w", "An exception occured while trying to create serial connection")
                 return
-        container_stack = Application.getInstance().getGlobalContainerStack()
+        container_stack = CuraApplication.getInstance().getGlobalContainerStack()
         num_extruders = container_stack.getProperty("machine_extruder_count", "value")
         # Ensure that a printer is created.
         self._printers = [PrinterOutputModel(output_controller=GenericOutputController(self), number_of_extruders=num_extruders)]
@@ -277,13 +277,12 @@ class USBPrinterOutputDevice(PrinterOutputDevice):
         if self._serial is None or self._connection_state != ConnectionState.connected:
             return
 
-        if type(command == str):
+        new_command = cast(bytes, command) if type(command) is bytes else cast(str, command).encode() # type: bytes
-            command = command.encode()
+        if not new_command.endswith(b"\n"):
-        if not command.endswith(b"\n"):
+            new_command += b"\n"
-            command += b"\n"
         try:
             self._command_received.clear()
-            self._serial.write(command)
+            self._serial.write(new_command)
         except SerialTimeoutException:
             Logger.log("w", "Timeout when sending command to printer via USB.")
             self._command_received.set()

plugins/USBPrinting/USBPrinterOutputDeviceManager.py

@@ -179,7 +179,7 @@ class USBPrinterOutputDeviceManager(QObject, OutputDevicePlugin):
 
         return list(base_list)
 
-    __instance = None
+    __instance = None # type: USBPrinterOutputDeviceManager
 
     @classmethod
     def getInstance(cls, *args, **kwargs) -> "USBPrinterOutputDeviceManager":

plugins/VersionUpgrade/VersionUpgrade21to22/Profile.py

@@ -44,20 +44,18 @@ class Profile:
 
         # Parse the general section.
         self._name = parser.get("general", "name")
-        self._type = parser.get("general", "type", fallback = None)
+        self._type = parser.get("general", "type")
+        self._weight = None
         if "weight" in parser["general"]:
             self._weight = int(parser.get("general", "weight"))
-        else:
+        self._machine_type_id = parser.get("general", "machine_type")
-            self._weight = None
+        self._machine_variant_name = parser.get("general", "machine_variant")
-        self._machine_type_id = parser.get("general", "machine_type", fallback = None)
+        self._machine_instance_name = parser.get("general", "machine_instance")
-        self._machine_variant_name = parser.get("general", "machine_variant", fallback = None)
+        self._material_name = None
-        self._machine_instance_name = parser.get("general", "machine_instance", fallback = None)
         if "material" in parser["general"]: #Note: Material name is unused in this upgrade.
             self._material_name = parser.get("general", "material")
         elif self._type == "material":
-            self._material_name = parser.get("general", "name", fallback = None)
+            self._material_name = parser.get("general", "name")
-        else:
-            self._material_name = None
 
         # Parse the settings.
         self._settings = {} # type: Dict[str,str]

plugins/XmlMaterialProfile/XmlMaterialProfile.py

@@ -6,8 +6,10 @@ import io
 import json #To parse the product-to-id mapping file.
 import os.path #To find the product-to-id mapping.
 import sys
-from typing import Any, Dict, List, Optional
+from typing import Any, Dict, List, Optional, cast
 import xml.etree.ElementTree as ET
+from typing import Dict
+from typing import Iterator
 
 from UM.Resources import Resources
 from UM.Logger import Logger
@@ -132,7 +134,7 @@ class XmlMaterialProfile(InstanceContainer):
                               "version": self.CurrentFdmMaterialVersion})
 
         ## Begin Metadata Block
-        builder.start("metadata")
+        builder.start("metadata") # type: ignore
 
         metadata = copy.deepcopy(self.getMetaData())
         # setting_version is derived from the "version" tag in the schema, so don't serialize it into a file
@@ -156,21 +158,21 @@ class XmlMaterialProfile(InstanceContainer):
         metadata.pop("name", "")
 
         ## Begin Name Block
-        builder.start("name")
+        builder.start("name") # type: ignore
 
-        builder.start("brand")
+        builder.start("brand") # type: ignore
         builder.data(metadata.pop("brand", ""))
         builder.end("brand")
 
-        builder.start("material")
+        builder.start("material") # type: ignore
         builder.data(metadata.pop("material", ""))
         builder.end("material")
 
-        builder.start("color")
+        builder.start("color") # type: ignore
         builder.data(metadata.pop("color_name", ""))
         builder.end("color")
 
-        builder.start("label")
+        builder.start("label") # type: ignore
         builder.data(self.getName())
         builder.end("label")
 
@@ -178,7 +180,7 @@ class XmlMaterialProfile(InstanceContainer):
         ## End Name Block
 
         for key, value in metadata.items():
-            builder.start(key)
+            builder.start(key) # type: ignore
             if value is not None: #Nones get handled well by the builder.
                 #Otherwise the builder always expects a string.
                 #Deserialize expects the stringified version.
@@ -190,10 +192,10 @@ class XmlMaterialProfile(InstanceContainer):
         ## End Metadata Block
 
         ## Begin Properties Block
-        builder.start("properties")
+        builder.start("properties") # type: ignore
 
         for key, value in properties.items():
-            builder.start(key)
+            builder.start(key) # type: ignore
             builder.data(value)
             builder.end(key)
 
@@ -201,14 +203,14 @@ class XmlMaterialProfile(InstanceContainer):
         ## End Properties Block
 
         ## Begin Settings Block
-        builder.start("settings")
+        builder.start("settings") # type: ignore
 
         if self.getMetaDataEntry("definition") == "fdmprinter":
             for instance in self.findInstances():
                 self._addSettingElement(builder, instance)
 
-        machine_container_map = {}
+        machine_container_map = {} # type: Dict[str, InstanceContainer]
-        machine_variant_map = {}
+        machine_variant_map = {} # type: Dict[str, Dict[str, Any]]
 
         variant_manager = CuraApplication.getInstance().getVariantManager()
 
@@ -248,7 +250,7 @@ class XmlMaterialProfile(InstanceContainer):
                     product = product_name
                     break
 
-            builder.start("machine")
+            builder.start("machine") # type: ignore
             builder.start("machine_identifier", {
                 "manufacturer": container.getMetaDataEntry("machine_manufacturer",
                                                            definition_metadata.get("manufacturer", "Unknown")),
@@ -264,7 +266,7 @@ class XmlMaterialProfile(InstanceContainer):
                 self._addSettingElement(builder, instance)
 
             # Find all hotend sub-profiles corresponding to this material and machine and add them to this profile.
-            buildplate_dict = {}
+            buildplate_dict = {} # type: Dict[str, Any]
             for variant_name, variant_dict in machine_variant_map[definition_id].items():
                 variant_type = variant_dict["variant_node"].metadata["hardware_type"]
                 from cura.Machines.VariantManager import VariantType
@@ -812,11 +814,14 @@ class XmlMaterialProfile(InstanceContainer):
                 if label is not None and label.text is not None:
                     base_metadata["name"] = label.text
                 else:
-                    base_metadata["name"] = cls._profile_name(material.text, color.text)
+                    if material is not None and color is not None:
+                        base_metadata["name"] = cls._profile_name(material.text, color.text)
+                    else:
+                        base_metadata["name"] = "Unknown Material"
 
-                base_metadata["brand"] = brand.text if brand.text is not None else "Unknown Brand"
+                base_metadata["brand"] = brand.text if brand is not None and brand.text is not None else "Unknown Brand"
-                base_metadata["material"] = material.text if material.text is not None else "Unknown Type"
+                base_metadata["material"] = material.text if material is not None and material.text is not None else "Unknown Type"
-                base_metadata["color_name"] = color.text if color.text is not None else "Unknown Color"
+                base_metadata["color_name"] = color.text if color is not None and color.text is not None else "Unknown Color"
                 continue
 
             #Setting_version is derived from the "version" tag in the schema earlier, so don't set it here.
@@ -836,13 +841,13 @@ class XmlMaterialProfile(InstanceContainer):
             tag_name = _tag_without_namespace(entry)
             property_values[tag_name] = entry.text
 
-        base_metadata["approximate_diameter"] = str(round(float(property_values.get("diameter", 2.85)))) # In mm
+        base_metadata["approximate_diameter"] = str(round(float(cast(float, property_values.get("diameter", 2.85))))) # In mm
         base_metadata["properties"] = property_values
         base_metadata["definition"] = "fdmprinter"
 
         compatible_entries = data.iterfind("./um:settings/um:setting[@key='hardware compatible']", cls.__namespaces)
         try:
-            common_compatibility = cls._parseCompatibleValue(next(compatible_entries).text)
+            common_compatibility = cls._parseCompatibleValue(next(compatible_entries).text) # type: ignore
         except StopIteration: #No 'hardware compatible' setting.
             common_compatibility = True
         base_metadata["compatible"] = common_compatibility
@@ -856,7 +861,8 @@ class XmlMaterialProfile(InstanceContainer):
             for entry in machine.iterfind("./um:setting", cls.__namespaces):
                 key = entry.get("key")
                 if key == "hardware compatible":
-                    machine_compatibility = cls._parseCompatibleValue(entry.text)
+                    if entry.text is not None:
+                        machine_compatibility = cls._parseCompatibleValue(entry.text)
 
             for identifier in machine.iterfind("./um:machine_identifier", cls.__namespaces):
                 machine_id_list = product_id_map.get(identifier.get("product"), [])
@@ -864,11 +870,11 @@ class XmlMaterialProfile(InstanceContainer):
                     machine_id_list = cls.getPossibleDefinitionIDsFromName(identifier.get("product"))
 
                 for machine_id in machine_id_list:
-                    definition_metadata = ContainerRegistry.getInstance().findDefinitionContainersMetadata(id = machine_id)
+                    definition_metadatas = ContainerRegistry.getInstance().findDefinitionContainersMetadata(id = machine_id)
-                    if not definition_metadata:
+                    if not definition_metadatas:
                         continue
 
-                    definition_metadata = definition_metadata[0]
+                    definition_metadata = definition_metadatas[0]
 
                     machine_manufacturer = identifier.get("manufacturer", definition_metadata.get("manufacturer", "Unknown")) #If the XML material doesn't specify a manufacturer, use the one in the actual printer definition.
 
@@ -891,7 +897,7 @@ class XmlMaterialProfile(InstanceContainer):
                     result_metadata.append(new_material_metadata)
 
                     buildplates = machine.iterfind("./um:buildplate", cls.__namespaces)
-                    buildplate_map = {}
+                    buildplate_map = {} # type: Dict[str, Dict[str, bool]]
                     buildplate_map["buildplate_compatible"] = {}
                     buildplate_map["buildplate_recommended"] = {}
                     for buildplate in buildplates:
@@ -912,10 +918,11 @@ class XmlMaterialProfile(InstanceContainer):
                         buildplate_recommended = True
                         for entry in settings:
                             key = entry.get("key")
-                            if key == "hardware compatible":
+                            if entry.text is not None:
-                                buildplate_compatibility = cls._parseCompatibleValue(entry.text)
+                                if key == "hardware compatible":
-                            elif key == "hardware recommended":
+                                    buildplate_compatibility = cls._parseCompatibleValue(entry.text)
-                                buildplate_recommended = cls._parseCompatibleValue(entry.text)
+                                elif key == "hardware recommended":
+                                    buildplate_recommended = cls._parseCompatibleValue(entry.text)
 
                         buildplate_map["buildplate_compatible"][buildplate_id] = buildplate_compatibility
                         buildplate_map["buildplate_recommended"][buildplate_id] = buildplate_recommended
@@ -929,7 +936,8 @@ class XmlMaterialProfile(InstanceContainer):
                         for entry in hotend.iterfind("./um:setting", cls.__namespaces):
                             key = entry.get("key")
                             if key == "hardware compatible":
-                                hotend_compatibility = cls._parseCompatibleValue(entry.text)
+                                if entry.text is not None:
+                                    hotend_compatibility = cls._parseCompatibleValue(entry.text)
 
                         new_hotend_specific_material_id = container_id + "_" + machine_id + "_" + hotend_name.replace(" ", "_")
 

run_mypy.py

@@ -44,7 +44,7 @@ def main():
 
     for mod in mods:
         print("------------- Checking module {mod}".format(**locals()))
-        result = subprocess.run([sys.executable, mypyModule, "-p", mod])
+        result = subprocess.run([sys.executable, mypyModule, "-p", mod, "--ignore-missing-imports"])
         if result.returncode != 0:
             print("\nModule {mod} failed checking. :(".format(**locals()))
             return 1

tests/Settings/TestExtruderStack.py

@@ -340,26 +340,4 @@ def test_setPropertyUser(key, property, value, extruder_stack):
 
     extruder_stack.setProperty(key, property, value) #The actual test.
 
-    extruder_stack.userChanges.setProperty.assert_called_once_with(key, property, value) #Make sure that the user container gets a setProperty call.
+    extruder_stack.userChanges.setProperty.assert_called_once_with(key, property, value) #Make sure that the user container gets a setProperty call.
-
-##  Tests setting properties on specific containers on the global stack.
-@pytest.mark.parametrize("target_container,    stack_variable", [
-                        ("user",               "userChanges"),
-                        ("quality_changes",    "qualityChanges"),
-                        ("quality",            "quality"),
-                        ("material",           "material"),
-                        ("variant",            "variant")
-])
-def test_setPropertyOtherContainers(target_container, stack_variable, extruder_stack):
-    #Other parameters that don't need to be varied.
-    key = "layer_height"
-    property = "value"
-    value = 0.1337
-    #A mock container in the right spot.
-    container = unittest.mock.MagicMock()
-    container.getMetaDataEntry = unittest.mock.MagicMock(return_value = target_container)
-    setattr(extruder_stack, stack_variable, container) #For instance, set global_stack.qualityChanges = container.
-
-    extruder_stack.setProperty(key, property, value, target_container = target_container) #The actual test.
-
-    getattr(extruder_stack, stack_variable).setProperty.assert_called_once_with(key, property, value) #Make sure that the proper container gets a setProperty call.

tests/Settings/TestGlobalStack.py

@@ -481,27 +481,4 @@ def test_setPropertyUser(key, property, value, global_stack):
 
     global_stack.setProperty(key, property, value) #The actual test.
 
-    global_stack.userChanges.setProperty.assert_called_once_with(key, property, value) #Make sure that the user container gets a setProperty call.
+    global_stack.userChanges.setProperty.assert_called_once_with(key, property, value) #Make sure that the user container gets a setProperty call.
-
-##  Tests setting properties on specific containers on the global stack.
-@pytest.mark.parametrize("target_container,    stack_variable", [
-                        ("user",               "userChanges"),
-                        ("quality_changes",    "qualityChanges"),
-                        ("quality",            "quality"),
-                        ("material",           "material"),
-                        ("variant",            "variant"),
-                        ("definition_changes", "definitionChanges")
-])
-def test_setPropertyOtherContainers(target_container, stack_variable, global_stack):
-    #Other parameters that don't need to be varied.
-    key = "layer_height"
-    property = "value"
-    value = 0.1337
-    #A mock container in the right spot.
-    container = unittest.mock.MagicMock()
-    container.getMetaDataEntry = unittest.mock.MagicMock(return_value = target_container)
-    setattr(global_stack, stack_variable, container) #For instance, set global_stack.qualityChanges = container.
-
-    global_stack.setProperty(key, property, value, target_container = target_container) #The actual test.
-
-    getattr(global_stack, stack_variable).setProperty.assert_called_once_with(key, property, value) #Make sure that the proper container gets a setProperty call.