chore: setup ci lint job (#258)

Author: pieh

.github/workflows/lint.yml

@@ -0,0 +1,32 @@
+name: Lint
+
+on:
+  pull_request:
+    branches:
+      - main
+
+jobs:
+  lint:
+    name: Lint
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '18.x'
+          cache: 'npm'
+          cache-dependency-path: '**/package-lock.json'
+      - run: npm ci
+      - name: Lint
+        # github adds inline annotation for compact or stylish format
+        # which is different than our default for local usage
+        run: npm run lint -- --format=compact
+      - name: Types
+        run: npm run typecheck
+        # we still want to check types if lint fails just to know everything
+        # and not peel errors to uncover new ones of different type
+        if: always()

package.json

@@ -18,9 +18,10 @@
     "pretest": "node tests/prepare.mjs",
     "build": "node ./tools/build.js",
     "build:watch": "node ./tools/build.js --watch",
-    "lint": "eslint --cache --format=codeframe --max-warnings=0 src/**/*.ts",
+    "lint": "eslint --cache --format=codeframe --max-warnings=0 --ext .ts,.cts,.js src",
     "test": "vitest",
     "test:ci": "vitest run --reporter=default --retry=3",
+    "typecheck": "tsc --noEmit",
     "e2e": "playwright test",
     "e2e:ci": "playwright test"
   },