Configure ESLint

Author: qnighy

.eslintrc.cjs

@@ -0,0 +1,59 @@
+// @ts-check
+
+/** @type {import("eslint").Linter.Config} */
+const config = {
+  extends: [
+    "eslint:recommended",
+    "plugin:@typescript-eslint/recommended",
+    "plugin:node/recommended",
+    "prettier",
+  ],
+  plugins: ["@babel/development"],
+  parser: "@typescript-eslint/parser",
+  reportUnusedDisableDirectives: true,
+  rules: {
+    "@typescript-eslint/no-non-null-assertion": "off",
+    "@typescript-eslint/no-unused-vars": [
+      "warn",
+      {
+        varsIgnorePattern: "^_",
+        argsIgnorePattern: "^_",
+        caughtErrorsIgnorePattern: "^_",
+      },
+    ],
+    "no-constant-condition": [
+      "error",
+      {
+        checkLoops: false,
+      },
+    ],
+    "node/no-unsupported-features/es-syntax": "off",
+    // Specifying *.js for *.ts doesn't work now
+    "node/no-missing-import": "off",
+    // Disabling it until it skips type-only imports
+    "node/no-unpublished-import": "off",
+    // We target newer Node, so this is unnecessary
+    "no-inner-declarations": "off",
+  },
+  overrides: [
+    {
+      files: ["src/**/*.ts"],
+      extends: [
+        "plugin:@typescript-eslint/recommended-requiring-type-checking",
+      ],
+      parserOptions: {
+        project: ["./tsconfig.json"],
+        tsconfigRootDir: __dirname,
+      },
+    },
+    {
+      files: ["*.test.ts"],
+      extends: ["plugin:jest/recommended"],
+      rules: {
+        "node/no-unpublished-import": "off",
+      },
+    },
+  ],
+  ignorePatterns: ["cjs/dist/**/*", "dist/**/*", "coverage/**/*"],
+};
+module.exports = config;

.github/workflows/test.yml

@@ -23,7 +23,7 @@ jobs:
       run: yarn test
     - name: Typecheck
       run: yarn tsc
-    # - name: Lint
-    #   run: yarn lint --max-warnings 0
+    - name: Lint
+      run: yarn lint --max-warnings 0
     - name: Check formatting
       run: yarn fmt:check

.vim/coc-settings.json

@@ -1,4 +1,6 @@
 {
   "workspace.workspaceFolderCheckCwd": false,
-  "tsserver.tsdk": ".yarn/sdks/typescript/lib"
+  "tsserver.tsdk": ".yarn/sdks/typescript/lib",
+  "eslint.packageManager": "yarn",
+  "eslint.nodePath": ".yarn/sdks"
 }

.vscode/extensions.json

@@ -1,6 +1,7 @@
 {
   "recommendations": [
     "arcanis.vscode-zipfs",
-    "esbenp.prettier-vscode"
+    "esbenp.prettier-vscode",
+    "dbaeumer.vscode-eslint"
   ]
 }

.yarn/sdks/eslint/bin/eslint.js

@@ -0,0 +1,20 @@
+#!/usr/bin/env node
+
+const {existsSync} = require(`fs`);
+const {createRequire} = require(`module`);
+const {resolve} = require(`path`);
+
+const relPnpApiPath = "../../../../.pnp.cjs";
+
+const absPnpApiPath = resolve(__dirname, relPnpApiPath);
+const absRequire = createRequire(absPnpApiPath);
+
+if (existsSync(absPnpApiPath)) {
+  if (!process.versions.pnp) {
+    // Setup the environment to be able to require eslint/bin/eslint.js
+    require(absPnpApiPath).setup();
+  }
+}
+
+// Defer to the real eslint/bin/eslint.js your application uses
+module.exports = absRequire(`eslint/bin/eslint.js`);

.yarn/sdks/eslint/lib/api.js

@@ -0,0 +1,20 @@
+#!/usr/bin/env node
+
+const {existsSync} = require(`fs`);
+const {createRequire} = require(`module`);
+const {resolve} = require(`path`);
+
+const relPnpApiPath = "../../../../.pnp.cjs";
+
+const absPnpApiPath = resolve(__dirname, relPnpApiPath);
+const absRequire = createRequire(absPnpApiPath);
+
+if (existsSync(absPnpApiPath)) {
+  if (!process.versions.pnp) {
+    // Setup the environment to be able to require eslint
+    require(absPnpApiPath).setup();
+  }
+}
+
+// Defer to the real eslint your application uses
+module.exports = absRequire(`eslint`);

.yarn/sdks/eslint/package.json

@@ -0,0 +1,6 @@
+{
+  "name": "eslint",
+  "version": "8.37.0-sdk",
+  "main": "./lib/api.js",
+  "type": "commonjs"
+}

package.json

@@ -37,12 +37,14 @@
     "build:esm": "babel -x .ts -d dist src --ignore '**/*.test.ts'",
     "fmt": "prettier -w .",
     "fmt:check": "prettier -c .",
+    "lint": "eslint .",
     "prepack": "$npm_execpath build",
     "test": "NODE_OPTIONS='--experimental-vm-modules' yarn jest"
   },
   "devDependencies": {
     "@babel/cli": "^7.21.0",
     "@babel/core": "^7.21.3",
+    "@babel/eslint-plugin-development": "^7.19.1",
     "@babel/preset-env": "^7.20.2",
     "@babel/preset-typescript": "^7.21.0",
     "@babel/types": "^7.21.3",
@@ -51,8 +53,15 @@
     "@qnighy/dedent": "^0.1.1",
     "@types/babel__core": "^7.20.0",
     "@types/babel__traverse": "^7.18.3",
+    "@types/node": "^18.15.11",
+    "@typescript-eslint/eslint-plugin": "^5.57.0",
+    "@typescript-eslint/parser": "^5.57.0",
     "@yarnpkg/sdks": "^3.0.0-rc.40",
     "babel-jest": "^29.5.0",
+    "eslint": "^8.37.0",
+    "eslint-config-prettier": "^8.8.0",
+    "eslint-plugin-jest": "^27.2.1",
+    "eslint-plugin-node": "^11.1.0",
     "jest": "^29.5.0",
     "prettier": "^2.8.7",
     "ts-jest-resolver": "^2.0.1",

src/analysis.ts

@@ -225,7 +225,6 @@ function analyzeOuterCapturings(
 ): Set<string> {
   const capturings = new Set<string>();
   function visitIdent(path: NodePath<Identifier | JSXIdentifier>) {
-    path.getOuterBindingIdentifiers;
     const binding = path.scope.getBinding(path.node.name);
     if (!binding || binding.path.isAncestor(classPath)) {
       capturings.add(path.node.name);

src/analysis/class_fields.ts

@@ -270,7 +270,7 @@ export function analyzeClassFields(
           }
           constructor = itemPath as NodePath<ClassMethod>;
         } else {
-          throw new AnalysisError(`Not implemented yet: ${kind}`);
+          throw new AnalysisError(`Not implemented yet: ${kind as string}`);
         }
       } else if (isClassAccessorProperty(itemPath)) {
         throw new AnalysisError(`Not implemented yet: class accessor property`);