Add GitHub actions

.github/workflows/workflow.yml

@@ -0,0 +1,69 @@
+name: Build
+on: [push, pull_request]
+env:
+  # GitHub actions does not define this but should
+  CI: 'true'
+jobs:
+  combinations:
+    # git push --tags does not create any commits so should not trigger a new
+    # workflow. There are no ways to skip workflows, so we skip jobs instead
+    if: toJson(github.event.commits) != '[]'
+    strategy:
+      # Test on Windows/Mac/Linux using latest Node.js.
+      # Also test on Linux with older Node.js versions.
+      # We do not run each possible combination to make CI faster.
+      matrix:
+        os: [ubuntu-latest, macOS-latest, windows-latest]
+        node: [10.17.0, 13]
+        exclude:
+          - os: macOS-latest
+            node: 10.17.0
+          - os: windows-latest
+            node: 10.17.0
+      fail-fast: false
+    runs-on: ${{ matrix.os }}
+    # We do not use @actions/cache because restoring/saving cache currently
+    # takes more time than the time saved on `npm ci`
+    steps:
+      - name: Git checkout
+        uses: actions/checkout@v1
+      - name: Node.js ${{ matrix.node }}
+        uses: actions/setup-node@v1
+        with:
+          node-version: ${{ matrix.node }}
+      - name: Install dependencies
+        run: npm ci
+      - name: Linting
+        run: npx gulp check
+      - name: Build
+        run: npx gulp build
+      - name: Tests
+        run: npx gulp unit
+      - name: Upload test coverage
+        run: npx gulp uploadCoverage
+  # Performed after each OS + Node.js version combination has succeeded
+  final:
+    needs: combinations
+    runs-on: ubuntu-latest
+    steps:
+      - name: Git checkout
+        uses: actions/checkout@v1
+      - name: Node.js 13
+        uses: actions/setup-node@v1
+        with:
+          node-version: 13
+      - name: Install dependencies
+        run: npm ci
+      # Test coverage check must happen after tests for the whole matrix have been
+      # performed, so we get the merged coverage map
+      - name: Check test coverage
+        run: npx gulp checkCoverage
+      - name: Build
+        run: npx gulp build
+      - name: Deploy
+        if:
+          startsWith(github.event.head_commit.message, 'Release ') &&
+          github.event_name != 'pull_request'
+        run: npx gulp publish
+        env:
+          NPM_TOKEN: ${{ secrets.NPM_TOKEN }}