feat(linter): add setup-oxlint-bridge generator for ESLint/Oxlint coexistence

packages/eslint/generators.json

@@ -28,6 +28,11 @@
       "factory": "./src/generators/convert-to-inferred/convert-to-inferred",
       "schema": "./src/generators/convert-to-inferred/schema.json",
       "description": "Convert existing ESLint project(s) using `@nx/eslint:lint` executor to use `@nx/eslint/plugin`."
+    },
+    "setup-oxlint-bridge": {
+      "factory": "./src/generators/setup-oxlint-bridge/setup-oxlint-bridge",
+      "schema": "./src/generators/setup-oxlint-bridge/schema.json",
+      "description": "Install eslint-plugin-oxlint and inject the JITI bridge into ESLint flat config for Oxlint coexistence."
     }
   }
 }

packages/eslint/src/generators/setup-oxlint-bridge/schema.d.ts

@@ -0,0 +1,6 @@
+export interface SetupOxlintBridgeSchema {
+  skipPackageJson?: boolean;
+  skipFormat?: boolean;
+  keepExistingVersions?: boolean;
+  oxlintConfigPath?: string;
+}

packages/eslint/src/generators/setup-oxlint-bridge/schema.json

@@ -0,0 +1,30 @@
+{
+  "$schema": "https://json-schema.org/schema",
+  "$id": "SetupOxlintBridge",
+  "title": "Setup Oxlint Bridge",
+  "description": "Install eslint-plugin-oxlint and inject the JITI bridge into ESLint flat config so that ESLint automatically disables rules already handled by Oxlint.",
+  "type": "object",
+  "properties": {
+    "skipPackageJson": {
+      "type": "boolean",
+      "default": false,
+      "description": "Do not add dependencies to `package.json`."
+    },
+    "skipFormat": {
+      "type": "boolean",
+      "default": false,
+      "description": "Skip formatting files."
+    },
+    "keepExistingVersions": {
+      "type": "boolean",
+      "default": false,
+      "description": "Keep existing versions of dependencies already in `package.json`."
+    },
+    "oxlintConfigPath": {
+      "type": "string",
+      "default": "./oxlint.config.ts",
+      "description": "Relative path from the workspace root to the oxlint config file."
+    }
+  },
+  "required": []
+}

packages/eslint/src/generators/setup-oxlint-bridge/setup-oxlint-bridge.spec.ts

@@ -0,0 +1,218 @@
+import { createTreeWithEmptyWorkspace } from '@nx/devkit/testing';
+import { Tree, readJson } from '@nx/devkit';
+import {
+  setupOxlintBridgeGenerator,
+  injectOxlintBridge,
+} from './setup-oxlint-bridge';
+
+describe('setup-oxlint-bridge', () => {
+  let tree: Tree;
+
+  beforeEach(() => {
+    tree = createTreeWithEmptyWorkspace();
+  });
+
+  describe('generator', () => {
+    it('should throw if no ESLint config exists', async () => {
+      await expect(setupOxlintBridgeGenerator(tree, {})).rejects.toThrow(
+        'No ESLint config file found'
+      );
+    });
+
+    it('should throw if ESLint config is not flat config', async () => {
+      tree.write('.eslintrc.json', JSON.stringify({ root: true, rules: {} }));
+      await expect(setupOxlintBridgeGenerator(tree, {})).rejects.toThrow(
+        'does not appear to be a flat config'
+      );
+    });
+
+    it('should skip if eslint-plugin-oxlint is already present', async () => {
+      tree.write(
+        'eslint.config.mjs',
+        `import oxlint from 'eslint-plugin-oxlint';\nexport default [];\n`
+      );
+      const callback = await setupOxlintBridgeGenerator(tree, {});
+      // Content should not be modified further
+      const content = tree.read('eslint.config.mjs', 'utf-8');
+      expect(content).toContain('eslint-plugin-oxlint');
+      expect(content).not.toContain('buildFromOxlintConfig');
+    });
+
+    it('should add dependencies to package.json', async () => {
+      tree.write(
+        'eslint.config.mjs',
+        [
+          `import nx from '@nx/eslint-plugin';`,
+          '',
+          'export default [',
+          '  ...nx.configs["flat/base"],',
+          '];',
+          '',
+        ].join('\n')
+      );
+
+      await setupOxlintBridgeGenerator(tree, {});
+
+      const packageJson = readJson(tree, 'package.json');
+      expect(packageJson.devDependencies['eslint-plugin-oxlint']).toBeDefined();
+      expect(packageJson.devDependencies['jiti']).toBeDefined();
+    });
+
+    it('should inject the bridge into eslint.config.mjs', async () => {
+      tree.write(
+        'eslint.config.mjs',
+        [
+          `import nx from '@nx/eslint-plugin';`,
+          '',
+          'export default [',
+          '  ...nx.configs["flat/base"],',
+          '];',
+          '',
+        ].join('\n')
+      );
+
+      await setupOxlintBridgeGenerator(tree, {});
+
+      const content = tree.read('eslint.config.mjs', 'utf-8');
+      expect(content).toContain(`import oxlint from 'eslint-plugin-oxlint'`);
+      expect(content).toContain(`import { createJiti } from 'jiti'`);
+      expect(content).toContain('createJiti(import.meta.url)');
+      expect(content).toContain('jiti.import');
+      expect(content).toContain("reportUnusedDisableDirectives: 'off'");
+      expect(content).toContain('buildFromOxlintConfig(oxlintConfig)');
+    });
+
+    it('should respect custom oxlintConfigPath', async () => {
+      tree.write(
+        'eslint.config.mjs',
+        [
+          `import nx from '@nx/eslint-plugin';`,
+          '',
+          'export default [',
+          '  ...nx.configs["flat/base"],',
+          '];',
+          '',
+        ].join('\n')
+      );
+
+      await setupOxlintBridgeGenerator(tree, {
+        oxlintConfigPath: './tools/oxlint.config.ts',
+      });
+
+      const content = tree.read('eslint.config.mjs', 'utf-8');
+      expect(content).toContain('./tools/oxlint.config.ts');
+    });
+
+    it('should not add deps when skipPackageJson is true', async () => {
+      tree.write(
+        'eslint.config.mjs',
+        `import nx from '@nx/eslint-plugin';\nexport default [];\n`
+      );
+
+      await setupOxlintBridgeGenerator(tree, { skipPackageJson: true });
+
+      const packageJson = readJson(tree, 'package.json');
+      expect(
+        packageJson.devDependencies?.['eslint-plugin-oxlint']
+      ).toBeUndefined();
+    });
+  });
+
+  describe('injectOxlintBridge', () => {
+    it('should inject ESM bridge correctly', () => {
+      const input = [
+        `import nx from '@nx/eslint-plugin';`,
+        '',
+        'export default [',
+        '  ...nx.configs["flat/base"],',
+        '  ...nx.configs["flat/typescript"],',
+        '];',
+      ].join('\n');
+
+      const result = injectOxlintBridge(input, 'mjs', './oxlint.config.ts');
+
+      expect(result).toContain(`import oxlint from 'eslint-plugin-oxlint'`);
+      expect(result).toContain(`import { createJiti } from 'jiti'`);
+      expect(result).toContain('createJiti(import.meta.url)');
+      expect(result).toContain(`await jiti.import('./oxlint.config.ts')`);
+      expect(result).toContain("reportUnusedDisableDirectives: 'off'");
+      expect(result).toContain('...oxlint.buildFromOxlintConfig(oxlintConfig)');
+      // buildFromOxlintConfig should be the last thing before ];
+      const closingIdx = result.lastIndexOf('];');
+      const beforeClosing = result.slice(0, closingIdx);
+      expect(beforeClosing.trimEnd()).toMatch(
+        /buildFromOxlintConfig\(oxlintConfig\),?$/
+      );
+    });
+
+    it('should inject CJS bridge correctly', () => {
+      const input = [
+        `const nx = require('@nx/eslint-plugin');`,
+        '',
+        'module.exports = [',
+        '  ...nx.configs["flat/base"],',
+        '];',
+      ].join('\n');
+
+      const result = injectOxlintBridge(input, 'cjs', './oxlint.config.ts');
+
+      expect(result).toContain(`require('eslint-plugin-oxlint')`);
+      expect(result).toContain(`require('jiti')`);
+      expect(result).toContain('createJiti(__filename)');
+      expect(result).toContain("reportUnusedDisableDirectives: 'off'");
+      expect(result).toContain('...oxlint.buildFromOxlintConfig(oxlintConfig)');
+    });
+
+    it('should add trailing comma to last existing element', () => {
+      const input = [
+        `import nx from '@nx/eslint-plugin';`,
+        '',
+        'export default [',
+        '  ...nx.configs["flat/base"]',
+        '];',
+      ].join('\n');
+
+      const result = injectOxlintBridge(input, 'mjs', './oxlint.config.ts');
+
+      // The existing element without trailing comma should get one
+      expect(result).toContain('flat/base"],');
+    });
+
+    it('should not duplicate comma if already present', () => {
+      const input = [
+        `import nx from '@nx/eslint-plugin';`,
+        '',
+        'export default [',
+        '  ...nx.configs["flat/base"],',
+        '];',
+      ].join('\n');
+
+      const result = injectOxlintBridge(input, 'mjs', './oxlint.config.ts');
+
+      // Should not produce double comma
+      expect(result).not.toContain(',,');
+    });
+
+    it('should preserve the export default structure', () => {
+      const input = [
+        `import nx from '@nx/eslint-plugin';`,
+        `import globals from 'globals';`,
+        '',
+        'export default [',
+        '  { ignores: ["**/dist"] },',
+        '  ...nx.configs["flat/base"],',
+        '  { languageOptions: { globals: { ...globals.browser } } },',
+        '];',
+      ].join('\n');
+
+      const result = injectOxlintBridge(input, 'mjs', './oxlint.config.ts');
+
+      expect(result).toContain('export default [');
+      expect(result).toContain('{ ignores: ["**/dist"] }');
+      expect(result).toContain('flat/base');
+      expect(result).toContain('globals.browser');
+      expect(result).toContain('buildFromOxlintConfig');
+      expect(result).toMatch(/\];/);
+    });
+  });
+});