glob (#268)

packages/glob/src/internal-path.ts

@@ -0,0 +1,113 @@
+import * as assert from 'assert'
+import * as path from 'path'
+import * as pathHelper from './internal-path-helper'
+
+const IS_WINDOWS = process.platform === 'win32'
+
+/**
+ * Helper class for parsing paths into segments
+ */
+export class Path {
+  segments: string[] = []
+
+  /**
+   * Constructs a Path
+   * @param itemPath Path or array of segments
+   */
+  constructor(itemPath: string | string[]) {
+    // String
+    if (typeof itemPath === 'string') {
+      assert(itemPath, `Parameter 'itemPath' must not be empty`)
+
+      // Normalize slashes and trim unnecessary trailing slash
+      itemPath = pathHelper.safeTrimTrailingSeparator(itemPath)
+
+      // Not rooted
+      if (!pathHelper.hasRoot(itemPath)) {
+        this.segments = itemPath.split(path.sep)
+      }
+      // Rooted
+      else {
+        // Add all segments, while not at the root
+        let remaining = itemPath
+        let dir = pathHelper.dirname(remaining)
+        while (dir !== remaining) {
+          // Add the segment
+          const basename = path.basename(remaining)
+          this.segments.unshift(basename)
+
+          // Truncate the last segment
+          remaining = dir
+          dir = pathHelper.dirname(remaining)
+        }
+
+        // Remainder is the root
+        this.segments.unshift(remaining)
+      }
+    }
+    // Array
+    else {
+      // Must not be empty
+      assert(
+        itemPath.length > 0,
+        `Parameter 'itemPath' must not be an empty array`
+      )
+
+      // Each segment
+      for (let i = 0; i < itemPath.length; i++) {
+        let segment = itemPath[i]
+
+        // Must not be empty
+        assert(
+          segment,
+          `Parameter 'itemPath' must not contain any empty segments`
+        )
+
+        // Normalize slashes
+        segment = pathHelper.normalizeSeparators(itemPath[i])
+
+        // Root segment
+        if (i === 0 && pathHelper.hasRoot(segment)) {
+          segment = pathHelper.safeTrimTrailingSeparator(segment)
+          assert(
+            segment === pathHelper.dirname(segment),
+            `Parameter 'itemPath' root segment contains information for multiple segments`
+          )
+          this.segments.push(segment)
+        }
+        // All other segments
+        else {
+          // Must not contain slash
+          assert(
+            !segment.includes(path.sep),
+            `Parameter 'itemPath' contains unexpected path separators`
+          )
+          this.segments.push(segment)
+        }
+      }
+    }
+  }
+
+  /**
+   * Converts the path to it's string representation
+   */
+  toString(): string {
+    // First segment
+    let result = this.segments[0]
+
+    // All others
+    let skipSlash =
+      result.endsWith(path.sep) || (IS_WINDOWS && /^[A-Z]:$/i.test(result))
+    for (let i = 1; i < this.segments.length; i++) {
+      if (skipSlash) {
+        skipSlash = false
+      } else {
+        result += path.sep
+      }
+
+      result += this.segments[i]
+    }
+
+    return result
+  }
+}