Add OSX build to CI, fix OSX builds (#6492)

Build a single sketch using a Travis-CI OSX instance to validate the
toolchain works properly on Macs.

Update the installed python3 symlink to point to the proper spot for OSX
(Python3 is in /usr/local/bin, not /usr/bin).

Fixes #6490

.travis.yml

@@ -107,6 +107,12 @@ jobs:
       script: $TRAVIS_BUILD_DIR/tests/buildm.sh
       env: CC=gcc-7 CXX=g++-7
 
+    - name: "MacOS can build sketches"
+      os: osx
+      stage: build
+      script: $TRAVIS_BUILD_DIR/tests/build.sh
+      env: MACOSX=1 BUILD_PARITY=custom mod=500 rem=1
+
     - name: "Boards"
       stage: build
       script: $TRAVIS_BUILD_DIR/tests/ci/build_boards.sh

package/package_esp8266com_index.template.json

@@ -177,10 +177,10 @@
                   },
                   {
                      "host": "x86_64-apple-darwin",
-                     "url": "https://github.com/earlephilhower/esp-quick-toolchain/releases/download/2.5.0-4/python3-placeholder.tar.gz",
+                     "url": "https://github.com/earlephilhower/esp-quick-toolchain/releases/download/2.5.0-4/python3-macosx-placeholder.tar.gz",
-                     "archiveFileName": "python3-placeholder.tar.gz",
+                     "archiveFileName": "python3-macosx-placeholder.tar.gz",
-                     "checksum": "SHA-256:d8cf9d9d66423d7b90978ebe285a73a6e8611995cd0d5e6273e929a0cf2c9850",
+                     "checksum": "SHA-256:5bfa0d4c2dc3edeeaa913f4eac42ef3ff0bf8c8fe9f11be112a8ca7911de2dae",
-                     "size": "191"
+                     "size": "198"
                   },
                   {
                      "host": "x86_64-pc-linux-gnu",

tests/common.sh

@@ -135,7 +135,7 @@ function install_libraries()
     pushd $HOME/Arduino/libraries
 
     # install ArduinoJson library
-    { test -r ArduinoJson-v6.11.0.zip || wget https://github.com/bblanchon/ArduinoJson/releases/download/v6.11.0/ArduinoJson-v6.11.0.zip; } && unzip ArduinoJson-v6.11.0.zip
+    { test -r ArduinoJson-v6.11.0.zip || wget https://github.com/bblanchon/ArduinoJson/releases/download/v6.11.0/ArduinoJson-v6.11.0.zip; } && unzip -q ArduinoJson-v6.11.0.zip
 
     popd
 }
@@ -145,8 +145,21 @@ function install_ide()
     local ide_path=$1
     local core_path=$2
     local debug=$3
-    test -r arduino.tar.xz || wget -O arduino.tar.xz https://www.arduino.cc/download.php?f=/arduino-nightly-linux64.tar.xz
+    if [ "$MACOSX" = "1" ]; then
-    tar xf arduino.tar.xz
+        # MACOS only has next-to-obsolete Python2 installed.  Install Python 3 from python.org
+        wget https://www.python.org/ftp/python/3.7.4/python-3.7.4-macosx10.9.pkg
+        sudo installer -pkg python-3.7.4-macosx10.9.pkg -target /
+        # Install the Python3 certificates, because SSL connections fail w/o them and of course they aren't installed by default.
+	( cd "/Applications/Python 3.7/" && sudo "./Install Certificates.command" )
+        # Hack to place arduino-builder in the same spot as sane OSes
+        test -r arduino.zip || wget -O arduino.zip https://downloads.arduino.cc/arduino-nightly-macosx.zip
+        unzip -q arduino.zip
+	mv Arduino.app arduino-nightly
+	mv arduino-nightly/Contents/Java/* arduino-nightly/.
+    else
+        test -r arduino.tar.xz || wget -O arduino.tar.xz https://www.arduino.cc/download.php?f=/arduino-nightly-linux64.tar.xz
+        tar xf arduino.tar.xz
+    fi
     mv arduino-nightly $ide_path
     cd $ide_path/hardware
     mkdir esp8266com
@@ -174,7 +187,6 @@ function install_arduino()
     echo -e "travis_fold:start:sketch_test_env_prepare"
     cd $TRAVIS_BUILD_DIR
     install_ide $HOME/arduino_ide $TRAVIS_BUILD_DIR $debug
-    which arduino
     cd $TRAVIS_BUILD_DIR
     install_libraries
     echo -e "travis_fold:end:sketch_test_env_prepare"