fix(migrate): broaden ESLint ecosystem cleanup and address review findings

Address findings from the extra-high-effort review of this PR:

- Iterate `peerDependencies` and `optionalDependencies` in addition to
  `devDependencies` and `dependencies`, matching the sister code path
  that handles vite/vitest overrides.
- Narrow the `@typescript-eslint/*` namespace removal to the
  ESLint-specific entry points (`eslint-plugin`, `parser`,
  `rule-tester`); preserve the reusable AST libraries (`utils`,
  `typescript-estree`, `scope-manager`, `types`) so codemods and doc
  generators that import them directly keep working.
- Recognize `@eslint/*`, `@eslint-community/*`, and `@angular-eslint/*`
  scopes as ESLint-only (e.g. `@eslint/js`, `@eslint/eslintrc`,
  `@eslint-community/eslint-utils`, `@angular-eslint/template-parser`).
- Recognize flat ESLint-only helpers: `eslint-formatter-*`, `eslintrc`,
  `eslint-utils`, `eslint-visitor-keys`, `eslint-scope`,
  `eslint-define-config`, `eslint-doc-generator`.
- Recognize `@nuxt/eslint` (Nuxt's ESLint integration module that
  `require`s `eslint` at runtime — useless after removal). The unit test
  that previously asserted this was preserved is now inverted.
- Strip `@types/` symmetrically: a `@types/<X>` is removable iff `<X>`
  is. Fixes the inconsistency where `@types/eslint-plugin-foo` was
  removed but `@types/eslint` survived.
- Delete a dependency field entirely (`devDependencies`,
  `peerDependencies`, etc.) when our cleanup emptied it, avoiding
  `"devDependencies": {}` noise. Visible in the
  `migration-eslint-monorepo` snap diff.
- Split `rewriteEslintPackageJson` into root vs workspace modes:
  workspace sub-packages get a conservative cleanup (only `eslint`
  itself), since they may intentionally publish plugins/configs as part
  of a shared lint-preset API consumed outside Vite+.
- Drop the broken `"include": ["src/**/*"]` from the
  `migration-eslint-type-aware` fixture's `tsconfig.json` (no `src/`
  directory exists).
- Expand the `migration-eslint-plugins-cleanup` fixture to exercise
  the wider matrix (scopes, formatters, `@types`, preserved
  `@typescript-eslint/utils`, peer `eslint`).

Deferred (out of scope for this PR):
- `detectEslintProject` gating on the literal `eslint` symbol — a
  project that has only `typescript-eslint` etc. never triggers the
  migration. Pre-existing.
- Stale `--rule '@typescript-eslint/...'` arguments in scripts after
  plugin removal — requires Rust ast-grep rule updates.
- Non-atomic `fs.writeFileSync` across N workspace `package.json` files;
  a SIGKILL mid-loop leaves the monorepo half-migrated. Pre-existing
  utility behavior.

Author: fengmk2

packages/cli/snap-tests-global/migration-eslint-monorepo/snap.txt

@@ -44,8 +44,7 @@
   "name": "@test/utils",
   "scripts": {
     "lint": "vp lint ."
-  },
-  "devDependencies": {}
+  }
 }
 
 > test ! -f eslint.config.mjs # check root eslint config is removed

packages/cli/snap-tests-global/migration-eslint-plugins-cleanup/package.json

@@ -6,15 +6,27 @@
     "lint": "eslint ."
   },
   "devDependencies": {
+    "@angular-eslint/template-parser": "^18.0.0",
+    "@eslint-community/eslint-utils": "^4.0.0",
+    "@eslint/js": "^9.0.0",
+    "@nuxt/eslint": "^0.5.0",
+    "@nuxt/kit": "^3.13.0",
+    "@types/eslint": "^9.0.0",
+    "@types/node": "^22.0.0",
     "@typescript-eslint/eslint-plugin": "^8.0.0",
     "@typescript-eslint/parser": "^8.0.0",
+    "@typescript-eslint/utils": "^8.0.0",
     "@vitejs/plugin-vue": "^6.0.0",
     "@vue/eslint-config-typescript": "^14.0.0",
     "eslint": "^9.0.0",
     "eslint-config-airbnb": "^19.0.0",
+    "eslint-formatter-pretty": "^6.0.0",
     "eslint-plugin-vue": "^10.0.0",
     "typescript-eslint": "^8.0.0",
     "vite": "^7.0.0",
     "vue": "^3.5.0"
+  },
+  "peerDependencies": {
+    "eslint": ">=9"
   }
 }

packages/cli/snap-tests-global/migration-eslint-plugins-cleanup/snap.txt

@@ -1,11 +1,11 @@
-> vp migrate --no-interactive # migration should remove ESLint and its plugins/configs
+> vp migrate --no-interactive # migration should remove ESLint, plugins, configs, scopes, formatters, and peer eslint
 ◇ Migrated . to Vite+
 • Node <semver>  pnpm <semver>
 • 4 config updates applied
 • ESLint rules migrated to Oxlint
 • TypeScript shim added for framework component files
 
-> cat package.json # check eslint, eslint-plugin-*, eslint-config-*, typescript-eslint and @typescript-eslint/* are removed
+> cat package.json # verify the comprehensive ESLint ecosystem cleanup
 {
   "name": "migration-eslint-plugins-cleanup",
   "scripts": {
@@ -15,6 +15,9 @@
     "prepare": "vp config"
   },
   "devDependencies": {
+    "@nuxt/kit": "^3.13.0",
+    "@types/node": "^22.0.0",
+    "@typescript-eslint/utils": "^8.0.0",
     "@vitejs/plugin-vue": "^6.0.0",
     "vite": "catalog:",
     "vue": "^3.5.0",

packages/cli/snap-tests-global/migration-eslint-plugins-cleanup/steps.json

@@ -1,7 +1,7 @@
 {
   "commands": [
-    "vp migrate --no-interactive # migration should remove ESLint and its plugins/configs",
-    "cat package.json # check eslint, eslint-plugin-*, eslint-config-*, typescript-eslint and @typescript-eslint/* are removed",
+    "vp migrate --no-interactive # migration should remove ESLint, plugins, configs, scopes, formatters, and peer eslint",
+    "cat package.json # verify the comprehensive ESLint ecosystem cleanup",
     "test ! -f eslint.config.mjs # check eslint config is removed"
   ]
 }

packages/cli/snap-tests-global/migration-eslint-type-aware/tsconfig.json

@@ -5,6 +5,5 @@
     "moduleResolution": "Bundler",
     "strict": true,
     "skipLibCheck": true
-  },
-  "include": ["src/**/*"]
+  }
 }

packages/cli/src/migration/__tests__/migrator.spec.ts

@@ -384,14 +384,128 @@ describe('rewriteEslintPackageJson', () => {
     expect(pkg.devDependencies).toEqual({ keepme: '^1.0.0' });
   });
 
-  it('preserves unrelated dependencies (e.g. @vitejs/plugin-vue, vue, vite)', () => {
+  it('removes @eslint/*, @eslint-community/*, and @angular-eslint/* scope packages', () => {
+    const pkgPath = writePkg({
+      devDependencies: {
+        eslint: '^9.0.0',
+        '@eslint/js': '^9.0.0',
+        '@eslint/eslintrc': '^3.0.0',
+        '@eslint/compat': '^1.0.0',
+        '@eslint-community/eslint-utils': '^4.0.0',
+        '@eslint-community/regexpp': '^4.0.0',
+        '@angular-eslint/template-parser': '^18.0.0',
+        '@angular-eslint/builder': '^18.0.0',
+        keepme: '^1.0.0',
+      },
+    });
+    rewriteEslintPackageJson(pkgPath);
+    const pkg = readJson(pkgPath);
+    expect(pkg.devDependencies).toEqual({ keepme: '^1.0.0' });
+  });
+
+  it('removes ESLint formatter, helper, and runtime-integration packages', () => {
+    const pkgPath = writePkg({
+      devDependencies: {
+        eslint: '^9.0.0',
+        'eslint-formatter-pretty': '^6.0.0',
+        'eslint-formatter-gitlab': '^5.0.0',
+        eslintrc: '^2.0.0',
+        'eslint-utils': '^3.0.0',
+        'eslint-visitor-keys': '^4.0.0',
+        'eslint-scope': '^8.0.0',
+        'eslint-define-config': '^2.0.0',
+        'eslint-doc-generator': '^2.0.0',
+        '@nuxt/eslint': '^0.5.0',
+        keepme: '^1.0.0',
+      },
+    });
+    rewriteEslintPackageJson(pkgPath);
+    const pkg = readJson(pkgPath);
+    expect(pkg.devDependencies).toEqual({ keepme: '^1.0.0' });
+  });
+
+  it('preserves reusable @typescript-eslint/* AST libraries (utils, typescript-estree, etc.)', () => {
+    const pkgPath = writePkg({
+      devDependencies: {
+        eslint: '^9.0.0',
+        '@typescript-eslint/parser': '^8.0.0',
+        '@typescript-eslint/eslint-plugin': '^8.0.0',
+        '@typescript-eslint/rule-tester': '^8.0.0',
+        '@typescript-eslint/utils': '^8.0.0',
+        '@typescript-eslint/typescript-estree': '^8.0.0',
+        '@typescript-eslint/scope-manager': '^8.0.0',
+        '@typescript-eslint/types': '^8.0.0',
+        vite: '^7.0.0',
+      },
+    });
+    rewriteEslintPackageJson(pkgPath);
+    const pkg = readJson(pkgPath);
+    expect(pkg.devDependencies).toEqual({
+      '@typescript-eslint/utils': '^8.0.0',
+      '@typescript-eslint/typescript-estree': '^8.0.0',
+      '@typescript-eslint/scope-manager': '^8.0.0',
+      '@typescript-eslint/types': '^8.0.0',
+      vite: '^7.0.0',
+    });
+  });
+
+  it('removes @types/<X> packages symmetrically with their runtime counterparts', () => {
+    const pkgPath = writePkg({
+      devDependencies: {
+        eslint: '^9.0.0',
+        '@types/eslint': '^9.0.0',
+        '@types/eslint-plugin-foo': '^1.0.0',
+        '@types/eslint-config-bar': '^1.0.0',
+        // Type-only counterpart of an ESLint plugin should also go.
+        '@types/eslint-scope': '^3.0.0',
+        // Unrelated @types should stay.
+        '@types/node': '^22.0.0',
+      },
+    });
+    rewriteEslintPackageJson(pkgPath);
+    const pkg = readJson(pkgPath);
+    expect(pkg.devDependencies).toEqual({ '@types/node': '^22.0.0' });
+  });
+
+  it('scrubs peerDependencies and optionalDependencies', () => {
+    const pkgPath = writePkg({
+      peerDependencies: {
+        eslint: '>=9',
+        'eslint-plugin-vue': '^10.0.0',
+      },
+      optionalDependencies: {
+        '@typescript-eslint/parser': '^8.0.0',
+      },
+      devDependencies: { vite: '^7.0.0' },
+    });
+    rewriteEslintPackageJson(pkgPath);
+    const pkg = readJson(pkgPath);
+    expect(pkg.peerDependencies).toBeUndefined();
+    expect(pkg.optionalDependencies).toBeUndefined();
+    expect(pkg.devDependencies).toEqual({ vite: '^7.0.0' });
+  });
+
+  it('deletes the dependency field entirely when our cleanup emptied it', () => {
+    const pkgPath = writePkg({
+      devDependencies: {
+        eslint: '^9.0.0',
+        'eslint-plugin-import': '^2.0.0',
+      },
+      dependencies: { 'eslint-config-airbnb': '^19.0.0' },
+    });
+    rewriteEslintPackageJson(pkgPath);
+    const pkg = readJson(pkgPath);
+    expect(pkg.devDependencies).toBeUndefined();
+    expect(pkg.dependencies).toBeUndefined();
+  });
+
+  it('preserves unrelated dependencies (e.g. @vitejs/plugin-vue, vue, vite, @nuxt/kit)', () => {
     const pkgPath = writePkg({
       devDependencies: {
         eslint: '^9.0.0',
         '@vitejs/plugin-vue': '^6.0.0',
         '@vue/runtime-core': '^3.5.0',
         '@nuxt/kit': '^3.13.0',
-        '@nuxt/eslint': '^0.5.0',
         vite: '^7.0.0',
       },
     });
@@ -401,9 +515,28 @@ describe('rewriteEslintPackageJson', () => {
       '@vitejs/plugin-vue': '^6.0.0',
       '@vue/runtime-core': '^3.5.0',
       '@nuxt/kit': '^3.13.0',
-      // `@nuxt/eslint` is the runtime package, not a config — preserved.
-      // (Only `@nuxt/eslint-config` matches the scoped-config pattern.)
-      '@nuxt/eslint': '^0.5.0',
+      vite: '^7.0.0',
+    });
+  });
+
+  it('workspace mode removes only `eslint` itself, not plugins or configs', () => {
+    const pkgPath = writePkg({
+      devDependencies: {
+        eslint: '^9.0.0',
+        'eslint-plugin-import': '^2.0.0',
+        'eslint-config-airbnb': '^19.0.0',
+        '@typescript-eslint/parser': '^8.0.0',
+        vite: '^7.0.0',
+      },
+    });
+    rewriteEslintPackageJson(pkgPath, 'workspace');
+    const pkg = readJson(pkgPath);
+    // Plugins/configs that the workspace package may publish as a shared
+    // lint-preset API are preserved; only `eslint` itself goes.
+    expect(pkg.devDependencies).toEqual({
+      'eslint-plugin-import': '^2.0.0',
+      'eslint-config-airbnb': '^19.0.0',
+      '@typescript-eslint/parser': '^8.0.0',
       vite: '^7.0.0',
     });
   });

packages/cli/src/migration/migrator.ts

@@ -303,13 +303,16 @@ export async function migrateEslintToOxlint(
   // Step 3: Delete all eslint config files at root
   deleteEslintConfigFiles(projectPath, options?.report, options?.silent);
 
-  // Step 4: Remove eslint dependency and rewrite eslint scripts (root only)
-  rewriteEslintPackageJson(path.join(projectPath, 'package.json'));
+  // Step 4: Remove eslint and all ESLint-ecosystem dependencies at the root,
+  // and rewrite eslint scripts.
+  rewriteEslintPackageJson(path.join(projectPath, 'package.json'), 'root');
 
-  // Step 4b: Rewrite eslint scripts in workspace packages
+  // Step 4b: Workspace packages get a conservative cleanup — only `eslint`
+  // itself is removed; plugins and configs they declare may be part of a
+  // shared lint-preset API consumed outside Vite+, so we leave them alone.
   if (packages) {
     for (const pkg of packages) {
-      rewriteEslintPackageJson(path.join(projectPath, pkg.path, 'package.json'));
+      rewriteEslintPackageJson(path.join(projectPath, pkg.path, 'package.json'), 'workspace');
     }
   }
 
@@ -337,52 +340,110 @@ function deleteEslintConfigFiles(basePath: string, report?: MigrationReport, sil
   }
 }
 
+// Bare names of packages whose sole purpose is to support ESLint. Removed
+// at root cleanup. Reusable AST libraries published under
+// `@typescript-eslint/*` (`utils`, `typescript-estree`, `scope-manager`,
+// `types`) are deliberately absent so codemods and doc generators that
+// import them directly keep working after migration.
+const ESLINT_ECOSYSTEM_NAMES = new Set<string>([
+  'eslint',
+  'typescript-eslint',
+  'eslintrc',
+  'eslint-utils',
+  'eslint-visitor-keys',
+  'eslint-scope',
+  'eslint-define-config',
+  'eslint-doc-generator',
+  // ESLint-only typescript-eslint entry points:
+  '@typescript-eslint/eslint-plugin',
+  '@typescript-eslint/parser',
+  '@typescript-eslint/rule-tester',
+  // Framework runtime modules that wire ESLint and break without it:
+  '@nuxt/eslint',
+]);
+
+// Flat name prefixes that mark an ESLint-only package.
+const ESLINT_ECOSYSTEM_PREFIXES = ['eslint-plugin-', 'eslint-config-', 'eslint-formatter-'];
+
+// Scopes whose every package is part of the ESLint ecosystem.
+//   @eslint/*           — official ESLint scope (e.g. @eslint/js, @eslint/eslintrc)
+//   @eslint-community/* — community-maintained ESLint dependencies
+//   @angular-eslint/*   — Angular's ESLint integration family
+const ESLINT_ECOSYSTEM_SCOPES = ['@eslint/', '@eslint-community/', '@angular-eslint/'];
+
 /**
  * Decide whether a dependency entry should be removed alongside `eslint`
- * itself. The set is conservative: only packages whose sole purpose is to
- * configure or extend ESLint. Anything else is preserved.
+ * itself. The set is intentionally broad: anything whose only purpose is
+ * to extend, configure, format, or wire ESLint becomes dead weight after
+ * migration. `@types/<X>` packages are checked symmetrically with `<X>`
+ * so type-only counterparts of removed runtime packages also go.
  */
 function isEslintEcosystemDep(name: string): boolean {
-  if (name === 'eslint') {
-    return true;
-  }
-  if (name.startsWith('eslint-plugin-') || name.startsWith('eslint-config-')) {
+  const stripped = name.startsWith('@types/') ? name.slice('@types/'.length) : name;
+  if (ESLINT_ECOSYSTEM_NAMES.has(stripped)) {
     return true;
   }
-  if (name === 'typescript-eslint') {
+  if (ESLINT_ECOSYSTEM_PREFIXES.some((p) => stripped.startsWith(p))) {
     return true;
   }
-  if (name.startsWith('@typescript-eslint/')) {
+  if (ESLINT_ECOSYSTEM_SCOPES.some((s) => stripped.startsWith(s))) {
     return true;
   }
-  // Scoped plugins/configs, e.g. `@vue/eslint-config-typescript`,
-  // `@nuxt/eslint-config`, `@stylistic/eslint-plugin`. These are all
-  // ESLint-only and have no other consumers.
-  if (/^@[^/]+\/eslint-(plugin|config)(-.+)?$/.test(name)) {
+  // Scoped plugins/configs/formatters, e.g.:
+  //   @vue/eslint-config-typescript
+  //   @stylistic/eslint-plugin-ts
+  //   @vitest/eslint-plugin
+  if (/^@[^/]+\/eslint-(plugin|config|formatter)(-.+)?$/.test(stripped)) {
     return true;
   }
   return false;
 }
 
-export function rewriteEslintPackageJson(packageJsonPath: string): void {
+/**
+ * Rewrite a project's `package.json` after ESLint has been migrated to
+ * Oxlint. Root cleanup is aggressive — every ESLint-ecosystem dependency
+ * is removed (see `isEslintEcosystemDep`). Workspace cleanup is
+ * conservative — only `eslint` itself is removed, because workspace
+ * sub-packages may intentionally publish ESLint plugins / configs as
+ * part of a shared lint-preset API consumed outside Vite+.
+ */
+export function rewriteEslintPackageJson(
+  packageJsonPath: string,
+  mode: 'root' | 'workspace' = 'root',
+): void {
   editJsonFile<{
     devDependencies?: Record<string, string>;
     dependencies?: Record<string, string>;
+    peerDependencies?: Record<string, string>;
+    optionalDependencies?: Record<string, string>;
     scripts?: Record<string, string>;
     'lint-staged'?: Record<string, string | string[]>;
   }>(packageJsonPath, (pkg) => {
     let changed = false;
-    for (const field of ['devDependencies', 'dependencies'] as const) {
+    const isRemovable = mode === 'root' ? isEslintEcosystemDep : (n: string) => n === 'eslint';
+    for (const field of [
+      'devDependencies',
+      'dependencies',
+      'peerDependencies',
+      'optionalDependencies',
+    ] as const) {
       const deps = pkg[field];
       if (!deps) {
         continue;
       }
+      let removedAny = false;
       for (const name of Object.keys(deps)) {
-        if (isEslintEcosystemDep(name)) {
+        if (isRemovable(name)) {
           delete deps[name];
           changed = true;
+          removedAny = true;
         }
       }
+      // Drop the field entirely if our cleanup emptied it — avoid
+      // leaving `"devDependencies": {}` noise in the output.
+      if (removedAny && Object.keys(deps).length === 0) {
+        delete pkg[field];
+      }
     }
     if (pkg.scripts) {
       const updated = rewriteEslint(JSON.stringify(pkg.scripts));