[Fix] no-unused-modules: don't error out when running with flat config and an eslintrc isn't present

michaelfaith · michaelfaith · commit bc014421d623 · 2024-12-20T09:14:45.000-06:00
This change adjusts how we're instantiating the FileEnumerator from eslint's unsupported api, in the case that the user is running with flat config.  We have to turn off the `useEslintrc` property on the ConfigArrayFactory that's passed into the FileEnumerator's constructor.

Note: This doesn't fix the fact that the FileEnumerator doesn't have knowledge of what the user's config is ignoring, it just prevents the rule from looking for a legacy / rc config and erroring out.  FileEnumerator used the rc config to understand which files to ignore.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -10,6 +10,9 @@ This change log adheres to standards from [Keep a CHANGELOG](https://keepachange
 - add [`enforce-node-protocol-usage`] rule and `import/node-version` setting ([#3024], thanks [@GoldStrikeArch] and [@sevenc-nanashi])
 - add TypeScript types ([#3097], thanks [@G-Rath])
 
+### Fixed
+- [`no-unused-modules`]: don't error out when running with flat config and an eslintrc isn't present ([#3116], thanks [@michaelfaith])
+
 ### Changed
 - [Docs] [`extensions`], [`order`]: improve documentation ([#3106], thanks [@Xunnamius])
 
@@ -1161,6 +1164,7 @@ for info on changes for earlier releases.
 
 [`memo-parser`]: ./memo-parser/README.md
 
+[#3116]: https://github.com/import-js/eslint-plugin-import/pull/3116
 [#3106]: https://github.com/import-js/eslint-plugin-import/pull/3106
 [#3097]: https://github.com/import-js/eslint-plugin-import/pull/3097
 [#3073]: https://github.com/import-js/eslint-plugin-import/pull/3073
diff --git a/examples/flat/package.json b/examples/flat/package.json
@@ -12,6 +12,7 @@
     "cross-env": "^7.0.3",
     "eslint": "^8.57.0",
     "eslint-plugin-import": "file:../..",
+    "move-file-cli": "^3.0.0",
     "typescript": "^5.4.5"
   }
 }
diff --git a/examples/v9/eslint.config.mjs b/examples/v9/eslint.config.mjs
@@ -0,0 +1,26 @@
+import importPlugin from 'eslint-plugin-import';
+import js from '@eslint/js';
+import tsParser from '@typescript-eslint/parser';
+
+export default [
+  js.configs.recommended,
+  importPlugin.flatConfigs.recommended,
+  importPlugin.flatConfigs.react,
+  importPlugin.flatConfigs.typescript,
+  {
+    files: ['**/*.{js,mjs,cjs,jsx,mjsx,ts,tsx,mtsx}'],
+    languageOptions: {
+      parser: tsParser,
+      ecmaVersion: 'latest',
+      sourceType: 'module',
+    },
+    ignores: ['eslint.config.mjs', '**/exports-unused.ts'],
+    rules: {
+      'no-unused-vars': 'off',
+      'import/no-dynamic-require': 'warn',
+      'import/no-nodejs-modules': 'warn',
+      'import/no-unused-modules': ['warn', { unusedExports: true }],
+      'import/no-cycle': 'warn',
+    },
+  },
+];
diff --git a/examples/v9/package.json b/examples/v9/package.json
@@ -0,0 +1,18 @@
+{
+  "name": "v9",
+  "version": "1.0.0",
+  "main": "index.js",
+  "scripts": {
+    "lint": "eslint src --report-unused-disable-directives"
+  },
+  "devDependencies": {
+    "@eslint/js": "^9.17.0",
+    "@types/node": "^20.14.5",
+    "@typescript-eslint/parser": "^8.18.0",
+    "cross-env": "^7.0.3",
+    "eslint": "^9.17.0",
+    "eslint-plugin-import": "file:../..",
+    "move-file-cli": "^3.0.0",
+    "typescript": "^5.4.5"
+  }
+}
diff --git a/examples/v9/src/depth-zero.js b/examples/v9/src/depth-zero.js
@@ -0,0 +1,3 @@
+import { foo } from "./es6/depth-one-dynamic";
+
+foo();
diff --git a/examples/v9/src/es6/depth-one-dynamic.js b/examples/v9/src/es6/depth-one-dynamic.js
@@ -0,0 +1,3 @@
+export function foo() {}
+
+export const bar = () => import("../depth-zero").then(({foo}) => foo);
diff --git a/examples/v9/src/exports-unused.ts b/examples/v9/src/exports-unused.ts
@@ -0,0 +1,12 @@
+export type ScalarType = string | number;
+export type ObjType = {
+  a: ScalarType;
+  b: ScalarType;
+};
+
+export const a = 13;
+export const b = 18;
+
+const defaultExport: ObjType = { a, b };
+
+export default defaultExport;
diff --git a/examples/v9/src/exports.ts b/examples/v9/src/exports.ts
@@ -0,0 +1,12 @@
+export type ScalarType = string | number;
+export type ObjType = {
+  a: ScalarType;
+  b: ScalarType;
+};
+
+export const a = 13;
+export const b = 18;
+
+const defaultExport: ObjType = { a, b };
+
+export default defaultExport;
diff --git a/examples/v9/src/imports.ts b/examples/v9/src/imports.ts
@@ -0,0 +1,7 @@
+//import c from './exports';
+import { a, b } from './exports';
+import type { ScalarType, ObjType } from './exports';
+
+import path from 'path';
+import fs from 'node:fs';
+import console from 'console';
diff --git a/examples/v9/src/jsx.tsx b/examples/v9/src/jsx.tsx
@@ -0,0 +1,3 @@
+const Components = () => {
+  return <></>;
+};
diff --git a/examples/v9/tsconfig.json b/examples/v9/tsconfig.json
@@ -0,0 +1,14 @@
+{
+  "compilerOptions": {
+    "jsx": "react-jsx",
+    "lib": ["ESNext"],
+    "target": "ESNext",
+    "module": "ESNext",
+    "rootDir": "./",
+    "moduleResolution": "Bundler",
+    "esModuleInterop": true,
+    "forceConsistentCasingInFileNames": true,
+    "strict": true,
+    "skipLibCheck": true
+  }
+}
diff --git a/package.json b/package.json
@@ -33,9 +33,10 @@
     "test": "npm run tests-only",
     "test-compiled": "npm run prepublish && BABEL_ENV=testCompiled mocha --compilers js:babel-register tests/src",
     "test-all": "node --require babel-register ./scripts/testAll",
-    "test-examples": "npm run build && npm run test-example:legacy && npm run test-example:flat",
+    "test-examples": "npm run build && npm run test-example:legacy && npm run test-example:flat && npm run test-example:v9",
     "test-example:legacy": "cd examples/legacy && npm install && npm run lint",
     "test-example:flat": "cd examples/flat && npm install && npm run lint",
+    "test-example:v9": "cd examples/v9 && npm install && npm run lint",
     "test-types": "npx --package typescript@latest tsc --noEmit index.d.ts",
     "prepublishOnly": "safe-publish-latest && npm run build",
     "prepublish": "not-in-publish || npm run prepublishOnly",
diff --git a/src/core/fsWalk.js b/src/core/fsWalk.js
diff --git a/src/rules/no-unused-modules.js b/src/rules/no-unused-modules.js

Original file line number	Diff line number	Diff line change
`@@ -12,6 +12,7 @@`
`12`	`12`	`"cross-env": "^7.0.3",`
`13`	`13`	`"eslint": "^8.57.0",`
`14`	`14`	`"eslint-plugin-import": "file:../..",`
	`15`	`+ "move-file-cli": "^3.0.0",`
`15`	`16`	`"typescript": "^5.4.5"`
`16`	`17`	`}`
`17`	`18`	`}`
Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,3 @@`
	`1`	`+import { foo } from "./es6/depth-one-dynamic";`
	`2`	`+`
	`3`	`+foo();`
Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,3 @@`
	`1`	`+export function foo() {}`
	`2`	`+`
	`3`	`+export const bar = () => import("../depth-zero").then(({foo}) => foo);`
Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,3 @@`
	`1`	`+const Components = () => {`
	`2`	`+ return <></>;`
	`3`	`+};`