setting envionment variables via matrix

.travis.yml

@@ -1,7 +1,3 @@
-os:
-    - linux
-    - osx
-language: c++
 before_install:
 - sh package/linux/travis-decrypt-key
 install:
@@ -51,6 +47,15 @@ notifications:
 dist: trusty
 env:
   matrix:
+    include:
+        - os: linux
+          language: c++
+          env: CXX=g++-7
+          env: CX=gcc-7
+          env: WXVERSION=pkg
+        - os: osx      
+          language: c++
+          env: WXVERSION=pkg
   global:
   - secure: eEVRZNMv7FM6jrOU9iAFkDhWxFQ1WtHBEaObImcvtFUxy6vWSt3ehFFeTRouj3uHQAnbvUzziDyvPPm8/95alv5g/du8ML6YzzqKBKfazM0xQ7SF6R2DQL8lfFIp+RSV7T02byEP1f1g7Zva7xH9szIlDcSfU0pXW4KWbkBFMd8=
   - secure: gj338h+qHGccTD/VQFmEJkqdg2McIe2pO0iZ4Ae9BvY5vxkIML4BpoYZQXQTqiAOETnUjlcknY9lx0hI/PfkDD9MSJc5BC/3fMYRCu3SgAclEwklWf9vvtodUeT69mtnZuw1zze1nTbExuOw2mepbqFjxKKMl+9l5oCz4O54fXU=

package/linux/travis-setup.sh

@@ -1,9 +1,9 @@
 #!/bin/bash
 # Script to configure travis environment prior to build
-WXVERSION=302
 CACHE=$HOME/cache
 mkdir -p $CACHE
-if [ $TRAVIS_OS_NAME == "linux" ]; then
+if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then
+    if [[ "$WXVERSION" -neq "pkg" ]]; then
         export WXDIR=$HOME/wx${WXVERSION}
         if [ ! -e $CACHE/boost-compiled.tar.bz2 ]; then
             echo "Downloading http://www.siusgs.com/slic3r/buildserver/boost_1_63_0.built.gcc-4.9.4-buildserver.tar.bz2 => $CACHE/boost-compiled.tar.bz2"
@@ -17,12 +17,10 @@ if [ $TRAVIS_OS_NAME == "linux" ]; then
         
         tar -C$HOME -xjf $CACHE/boost-compiled.tar.bz2
         tar -C$HOME -xjf $CACHE/wx${WXVERSION}.tar.bz2
+    fi
 
-    # Set some env variables specific to Travis Linux
-    export CXX=g++-7
-    export CC=gcc-7
-elif [ $TRAVIS_OS_NAME == "osx" ]; then
-    WXVERSION=311
+elif [[ "$TRAVIS_OS_NAME" == "osx" ]]; then
+    if [[ "$WXVERSION" -neq "pkg" ]]; then
         WXVER_EXPANDED=${WXVERSION:0:1}.${WXVERSION:1:1}.${WXVERSION:2:1}
         export WXDIR=$HOME/wx${WXVERSION}
         if [ ! -e $CACHE/wx${WXVERSION}-${TRAVIS_OS_NAME}.tar.bz2 ]; then
@@ -37,5 +35,7 @@ elif [ $TRAVIS_OS_NAME == "osx" ]; then
         fi
         export PATH=${PATH}:${WXDIR}
         cd $TRAVIS_BUILD_DIR # go back to the build dir
+    else
         brew install wxmac # install via homebrew
     fi
+fi