Add eslint to tests (#17)

Co-authored-by: Chengzhong Wu <[email protected]>

Author: kraenhansen

.github/workflows/lint.yml

@@ -0,0 +1,21 @@
+name: Lint
+
+on: [push, pull_request]
+
+permissions:
+  contents: read
+
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+    - name: Harden Runner
+      uses: step-security/harden-runner@f4a75cfd619ee5ce8d5b864b0d183aff3c69b55a # v2.13.1
+      with:
+        egress-policy: audit
+    - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+    - uses: actions/setup-node@2028fbc5c25fe9cf00d9f06a71cc4710d4507903 # v6.0.0
+      with:
+        node-version: 22.x
+    - run: npm ci
+    - run: npm run lint

eslint.config.js

@@ -0,0 +1,17 @@
+import { defineConfig, globalIgnores } from "eslint/config";
+
+export default defineConfig([
+  globalIgnores(["node"]),
+  {
+    files: ["tests/**/*.js"],
+    rules: {
+      // Test files are expected to be self-contained
+      "no-restricted-imports": ["error", {
+        patterns: ["*"],
+      }],
+      "no-restricted-globals": ["error",
+        { name: "require", message: "Test files are expected to be self-contained" }
+      ]
+    },
+  },
+]);