Create initial action

.github/workflows/main.yml

@@ -0,0 +1,64 @@
+name: Ruby
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  danger:
+    runs-on: ubuntu-latest
+    if: github.event_name  == 'pull_request'
+    steps:
+    - uses: actions/checkout@v2
+    - uses: actions/setup-ruby@v1
+      with:
+        ruby-version: '2.7'
+    - uses: MeilCli/danger-action@v5
+      with:
+        plugins_file: 'Gemfile'
+        install_path: 'vendor/bundle'
+        danger_file: 'Dangerfile'
+        danger_id: 'danger-pr'
+      env:
+        DANGER_GITHUB_API_TOKEN: ${{ secrets.github_token }}
+  test:
+    runs-on: ubuntu-18.04
+    strategy:
+      fail-fast: false
+      matrix:
+        ruby: [2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, head, debug, truffleruby, truffleruby-head]
+    steps:
+    - uses: actions/checkout@v2
+    - name: Set up Ruby
+      uses: ruby/setup-ruby@v1
+      with:
+        ruby-version: ${{ matrix.ruby }}
+        bundler-cache: true
+    - name: Install dependencies
+      run: bundle install
+    - name: Run tests
+      run: bundle exec rake
+  test-jruby:
+    runs-on: ubuntu-18.04
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu, macos]
+        jruby: [jruby, jruby-head]
+    steps:
+    - uses: actions/checkout@v2
+    - name: Set up Ruby
+      uses: ruby/setup-ruby@v1
+      with:
+        ruby-version: ${{ matrix.jruby }}
+        bundler-cache: true
+    - name: Install dependencies
+      env:
+        JRUBY_OPTS: --debug
+      run: bundle install
+    - name: Run tests
+      env:
+        JRUBY_OPTS: --debug
+      run: bundle exec rake