Added CI workflow.

.github/workflows/tests.yml

@@ -0,0 +1,45 @@
+# This workflow will do a clean install of node dependencies, build the source code and run tests across different versions of node
+# For more information see: https://help.github.com/actions/language-and-framework-guides/using-nodejs-with-github-actions
+
+name: Node.js CI
+
+on:
+  push:
+    branches: ['*']
+  pull_request:
+    branches: [master]
+
+jobs:
+  tests:
+    name: Node.js ${{matrix.node-version}} on ${{matrix.os}}
+    runs-on: ${{matrix.os}}
+
+    strategy:
+      matrix:
+        os: [ubuntu-latest, windows-latest, macOS-latest]
+        node-version: [10, 12, 14]
+
+    steps:
+    - uses: actions/checkout@v2
+      with:
+        submodules: true
+    - name: Setup Node.js ${{matrix.node-version}}
+      uses: actions/setup-node@v1
+      with:
+        node-version: ${{matrix.node-version}}
+    - name: Get NPM cache directory
+      id: npm-cache
+      run: echo "::set-output name=dir::$(npm config get cache)"
+    - name: Cache node modules
+      uses: actions/cache@v2
+      with:
+        path: ${{steps.npm-cache.outputs.dir}}
+        key: ${{runner.os}}-node-${{hashFiles('**/package-lock.json')}}
+        restore-keys: |
+          ${{runner.os}}-node-
+          ${{runner.os}}-
+    - name: Install the package and run tests
+      run: |
+        npm ci
+        npm run build --if-present
+        npm test