Chore: Attach GitHub Action for CI

.eslintrc

@@ -18,7 +18,7 @@
     },
     "extends": "eslint:recommended",
     "parserOptions": {
-        "ecmaVersion": 6,
+        "ecmaVersion": 10,
         "sourceType": "module"
     }
 }

.github/workflows/ci.yml

@@ -0,0 +1,41 @@
+name: CI
+
+on:
+  push:
+    paths-ignore:
+      - '*.md'
+      - 'LICENSE'
+      - 'index.d.ts'
+    branches:
+      - master
+  pull_request:
+    paths-ignore:
+      - '*.md'
+      - 'LICENSE'
+      - 'index.d.ts'
+    branches:
+      - master
+
+jobs:
+  test:
+    name: Node.js v${{ matrix.nodejs }} (${{ matrix.os }})
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        nodejs: [10, 12, 14]
+        os: [ubuntu-latest, windows-latest, macOS-latest]
+    steps:
+    - uses: actions/checkout@v2
+    - uses: actions/setup-node@v1
+      with:
+        node-version: ${{ matrix.nodejs }}
+
+    - name: Install
+      run: npm ci
+
+    - name: Linter
+      if: matrix.os != 'windows-latest'
+      run: npm run lint
+
+    - name: Test
+      run: npm test

index.js

@@ -110,7 +110,7 @@ class CssWriter {
 
 			// use `fileName` to prevent additional Rollup hashing
 			context.emitFile({ type: 'asset', fileName: mapfile, source });
-		}
+		};
 	}
 
 	write(dest = this.filename, map = !!this.map) {