chore: use github-actions to lint pull-requests (#3)

Author: smeijer

.github/workflows/lint.yml

@@ -0,0 +1,39 @@
+name: CI
+
+on:
+  pull_request:
+    types: [opened, synchronize, reopened]
+
+env:
+  NODE_VERSION: "12.x"
+
+jobs:
+  eslint:
+    name: Eslint
+    runs-on: ubuntu-latest
+    timeout-minutes: 5
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          fetch-depth: 0
+
+      - uses: actions/setup-node@v1
+        with:
+          node-version: "${{ env.NODE_VERSION }}"
+
+      - name: Cache node modules
+        uses: actions/cache@v1
+        with:
+          path: node_modules
+          key: ${{ runner.os }}-node_modules-${{ hashFiles('**/package-lock.json') }}
+
+      - name: Install Dependencies
+        if: steps.cache.outputs.cache-hit != 'true'
+        run: npm ci
+
+      - name: Fetch all branches
+        run: |
+          git fetch --no-tags --prune --depth=1 origin +refs/heads/*:refs/remotes/origin/*
+
+      - name: ESLint
+        run: npm run ci:lint -- $(git diff --diff-filter d --name-only origin/${{ github.base_ref }}...HEAD -- '*.js' '*.ts' '*.tsx')

package.json

@@ -7,7 +7,8 @@
     "start": "parcel index.html --open",
     "build": "parcel build index.html --no-cache",
     "lint": "eslint 'src/**/*.js' --quiet --fix",
-    "clean": "rimraf ./dist ./.cache"
+    "clean": "rimraf ./dist ./.cache",
+    "ci:lint": "eslint 'src/**/*.js' -c ./.eslintrc.js"
   },
   "dependencies": {
     "codemirror": "5.53.2",