Attempt at adding Github Actions CI

.github/workflows/build.yml

@@ -0,0 +1,79 @@
+name: CI
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    branches:
+      - master
+
+jobs:
+  build-linux:
+    name: Build Linux
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        cxx: [g++-9, clang++-9]
+    steps:
+    - uses: actions/checkout@v1
+    - name: cmake
+      run: CXX=${{ matrix.cxx }} cmake -G "Unix Makefiles" -DCMAKE_BUILD_TYPE=Release .
+    - name: build
+      run: make -j4
+    - name: test
+      run: ./flattests
+    - name: upload build artifacts
+      uses: actions/upload-artifact@v1
+      with:
+        name: Linux flatc binary ${{ matrix.cxx }}
+        path: flatc
+
+  build-windows:
+    name: Build Windows
+    runs-on: windows-latest
+    steps:
+    - uses: actions/checkout@v1
+    - name: Add msbuild to PATH
+      uses: microsoft/setup-msbuild@v1.0.0
+    - name: cmake
+      run: cmake -G "Visual Studio 16 2019" -A x64 -DCMAKE_BUILD_TYPE=Release .
+    - name: build
+      run: msbuild.exe FlatBuffers.sln /p:Configuration=Release /p:Platform=x64
+    - name: test
+      run: Release\flattests.exe
+    - name: upload build artifacts
+      uses: actions/upload-artifact@v1
+      with:
+        name: Windows flatc binary
+        path: Release\flatc.exe
+
+  build-mac:
+    name: Build Mac
+    runs-on: macos-latest
+    steps:
+    - uses: actions/checkout@v1
+    - name: cmake
+      run: cmake -G "Xcode" -DCMAKE_BUILD_TYPE=Release .
+    - name: build
+      run: xcodebuild -toolchain clang -configuration Release -target flattests
+    - name: test
+      run: Release/flattests
+    - name: upload build artifacts
+      uses: actions/upload-artifact@v1
+      with:
+        name: Mac flatc binary
+        path: Release/flatc
+
+  build-android:
+    name: Build Android (on Linux)
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v1
+    - name: set up JDK 1.8
+      uses: actions/setup-java@v1
+      with:
+        java-version: 1.8
+    - name: build
+      working-directory: android
+      run: bash ./gradlew buildDebug

android/build.gradle

@@ -17,15 +17,17 @@
 buildscript {
   repositories {
     jcenter()
+    google()
   }
   dependencies {
-    classpath 'com.android.tools.build:gradle:2.3.0'
+    classpath 'com.android.tools.build:gradle:3.2.1'
   }
 }
 
 allprojects {
   repositories {
     jcenter()
+    google()
   }
 }
 

android/gradle/wrapper/gradle-wrapper.properties

@@ -3,4 +3,4 @@ distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-4.0-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-4.6-all.zip