typescript-eslint · benmccann · Nov 10, 2025
diff --git a/packages/typescript-estree/package.json b/packages/typescript-estree/package.json
@@ -57,14 +57,12 @@
     "@typescript-eslint/types": "8.46.4",
     "@typescript-eslint/visitor-keys": "8.46.4",
     "debug": "^4.3.4",
-    "fast-glob": "^3.3.2",
-    "is-glob": "^4.0.3",
     "minimatch": "^9.0.4",
     "semver": "^7.6.0",
+    "tinyglobby": "^0.2.15",
     "ts-api-utils": "^2.1.0"
   },
   "devDependencies": {
-    "@types/is-glob": "^4.0.4",
     "@vitest/coverage-v8": "^3.1.3",
     "eslint": "*",
     "glob": "*",

diff --git a/packages/typescript-estree/src/parseSettings/resolveProjectList.ts b/packages/typescript-estree/src/parseSettings/resolveProjectList.ts
@@ -1,6 +1,5 @@
 import debug from 'debug';
-import { sync as globSync } from 'fast-glob';
-import isGlob from 'is-glob';
+import { globSync, isDynamicPattern } from 'tinyglobby';
 
 import type { CanonicalPath } from '../create-program/shared';
 import type { TSESTreeOptions } from '../parser-options';
@@ -57,10 +56,7 @@ export function resolveProjectList(
 
   const projectFolderIgnoreList = (
     options.projectFolderIgnoreList ?? ['**/node_modules/**']
-  )
-    .filter(folder => typeof folder === 'string')
-    // prefix with a ! for not match glob
-    .map(folder => (folder.startsWith('!') ? folder : `!${folder}`));
+  ).filter(folder => typeof folder === 'string');
 
   const cacheKey = getHash({
     project: sanitizedProjects,
@@ -86,18 +82,22 @@ export function resolveProjectList(
   }
 
   // Transform glob patterns into paths
-  const nonGlobProjects = sanitizedProjects.filter(project => !isGlob(project));
-  const globProjects = sanitizedProjects.filter(project => isGlob(project));
+  const nonGlobProjects = sanitizedProjects.filter(
+    project => !isDynamicPattern(project),
+  );
+  const globProjects = sanitizedProjects.filter(project =>
+    isDynamicPattern(project),
+  );
 
   let globProjectPaths: string[] = [];
 
   if (globProjects.length > 0) {
-    // Although fast-glob supports multiple patterns, fast-glob returns arbitrary order of results
-    // to improve performance. To ensure the order is correct, we need to call fast-glob for each pattern
+    // To ensure the order is correct, we need to glob for each pattern
     // separately and then concatenate the results in patterns' order.
     globProjectPaths = globProjects.flatMap(pattern =>
       globSync(pattern, {
         cwd: options.tsconfigRootDir,
+        expandDirectories: false,
         ignore: projectFolderIgnoreList,
       }),
     );

diff --git a/packages/typescript-estree/tests/lib/parse.test.ts b/packages/typescript-estree/tests/lib/parse.test.ts
@@ -1,8 +1,8 @@
 import type { CacheDurationSeconds } from '@typescript-eslint/types';
 
 import debug from 'debug';
-import * as fastGlobModule from 'fast-glob';
 import { join, resolve } from 'node:path';
+import * as tinyGlobbyModule from 'tinyglobby';
 
 import type { TSESTreeOptions } from '../../src/parser-options';
 
@@ -39,20 +39,21 @@ vi.mock(import('typescript'), async importOriginal => {
   };
 });
 
-vi.mock('fast-glob', async importOriginal => {
-  const fastGlob = await importOriginal<typeof fastGlobModule>();
+vi.mock('tinyglobby', async importOriginal => {
+  const tinyglobby = await importOriginal<typeof tinyGlobbyModule>();
 
   return {
-    ...fastGlob,
-    default: fastGlob.default,
-    sync: vi.fn(fastGlob.sync),
+    ...tinyglobby,
+    // eslint-disable-next-line @typescript-eslint/no-deprecated -- see #10215
+    globSync: vi.fn(tinyglobby.globSync),
   };
 });
 
 const createDefaultCompilerOptionsFromExtra = vi.mocked(
   sharedParserUtilsModule.createDefaultCompilerOptionsFromExtra,
 );
-const fastGlobSyncMock = vi.mocked(fastGlobModule.sync);
+// eslint-disable-next-line @typescript-eslint/no-deprecated -- seems like a bug in the rule
+const globSyncMock = vi.mocked(tinyGlobbyModule.globSync);
 
 /**
  * Aligns paths between environments, node for windows uses `\`, for linux and mac uses `/`
@@ -831,11 +832,11 @@ describe(parser.parseAndGenerateServices, () => {
     () => {
       describe('glob', () => {
         const project = ['./**/tsconfig.json', './**/tsconfig.extra.json'];
-        // fast-glob returns arbitrary order of results to improve performance.
-        // `resolveProjectList()` calls fast-glob for each pattern to ensure the
+        // tinyglobby returns arbitrary order of results to improve performance.
+        // `resolveProjectList()` runs a glob for each pattern to ensure the
         // order is correct.
         // Thus the expected call time of spy is the number of patterns.
-        const expectFastGlobCalls = project.length;
+        const expectedGlobCount = project.length;
         function doParse(lifetime: CacheDurationSeconds): void {
           parser.parseAndGenerateServices('const x = 1', {
             cacheLifetime: {
@@ -850,50 +851,46 @@ describe(parser.parseAndGenerateServices, () => {
 
         it('should cache globs if the lifetime is non-zero', () => {
           doParse(30);
-          expect(fastGlobSyncMock).toHaveBeenCalledTimes(expectFastGlobCalls);
+          expect(globSyncMock).toHaveBeenCalledTimes(expectedGlobCount);
           doParse(30);
-          // shouldn't call fast-glob again due to the caching
-          expect(fastGlobSyncMock).toHaveBeenCalledTimes(expectFastGlobCalls);
+          // shouldn't glob again due to the caching
+          expect(globSyncMock).toHaveBeenCalledTimes(expectedGlobCount);
         });
 
         it('should not cache globs if the lifetime is zero', () => {
           doParse(0);
-          expect(fastGlobSyncMock).toHaveBeenCalledTimes(expectFastGlobCalls);
+          expect(globSyncMock).toHaveBeenCalledTimes(expectedGlobCount);
           doParse(0);
-          // should call fast-glob again because we specified immediate cache expiry
-          expect(fastGlobSyncMock).toHaveBeenCalledTimes(
-            expectFastGlobCalls * 2,
-          );
+          // should glob again because we specified immediate cache expiry
+          expect(globSyncMock).toHaveBeenCalledTimes(2 * expectedGlobCount);
         });
 
         it('should evict the cache if the entry expires', () => {
           hrtimeSpy.mockReturnValueOnce([1, 0]);
 
           doParse(30);
-          expect(fastGlobSyncMock).toHaveBeenCalledTimes(expectFastGlobCalls);
+          expect(globSyncMock).toHaveBeenCalledTimes(expectedGlobCount);
 
           // wow so much time has passed
           hrtimeSpy.mockReturnValueOnce([Number.MAX_VALUE, 0]);
 
           doParse(30);
-          // shouldn't call fast-glob again due to the caching
-          expect(fastGlobSyncMock).toHaveBeenCalledTimes(
-            expectFastGlobCalls * 2,
-          );
+          // shouldn't glob again due to the caching
+          expect(globSyncMock).toHaveBeenCalledTimes(2 * expectedGlobCount);
         });
 
         it('should infinitely cache if passed Infinity', () => {
           hrtimeSpy.mockReturnValueOnce([1, 0]);
 
           doParse('Infinity');
-          expect(fastGlobSyncMock).toHaveBeenCalledTimes(expectFastGlobCalls);
+          expect(globSyncMock).toHaveBeenCalledTimes(expectedGlobCount);
 
           // wow so much time has passed
           hrtimeSpy.mockReturnValueOnce([Number.MAX_VALUE, 0]);
 
           doParse('Infinity');
-          // shouldn't call fast-glob again due to the caching
-          expect(fastGlobSyncMock).toHaveBeenCalledTimes(expectFastGlobCalls);
+          // shouldn't glob again due to the caching
+          expect(globSyncMock).toHaveBeenCalledTimes(expectedGlobCount);
         });
       });
     },

diff --git a/yarn.lock b/yarn.lock
@@ -5551,13 +5551,6 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@types/is-glob@npm:^4.0.4":
-  version: 4.0.4
-  resolution: "@types/is-glob@npm:4.0.4"
-  checksum: c790125e2d133d15c9783f6468995841cb06b5634b5c7b30aa32d23129f19d7dc271ec1a904bea4ca1e6a5ba19218a6602753d558f343b4fb8402fed25d17219
-  languageName: node
-  linkType: hard
-
 "@types/istanbul-lib-coverage@npm:*, @types/istanbul-lib-coverage@npm:^2.0.0":
   version: 2.0.4
   resolution: "@types/istanbul-lib-coverage@npm:2.0.4"
@@ -6186,20 +6179,18 @@ __metadata:
   version: 0.0.0-use.local
   resolution: "@typescript-eslint/typescript-estree@workspace:packages/typescript-estree"
   dependencies:
-    "@types/is-glob": ^4.0.4
     "@typescript-eslint/project-service": 8.46.4
     "@typescript-eslint/tsconfig-utils": 8.46.4
     "@typescript-eslint/types": 8.46.4
     "@typescript-eslint/visitor-keys": 8.46.4
     "@vitest/coverage-v8": ^3.1.3
     debug: ^4.3.4
     eslint: "*"
-    fast-glob: ^3.3.2
     glob: "*"
-    is-glob: ^4.0.3
     minimatch: ^9.0.4
     rimraf: "*"
     semver: ^7.6.0
+    tinyglobby: ^0.2.15
     ts-api-utils: ^2.1.0
     typescript: "*"
     vitest: ^3.1.3
@@ -10594,7 +10585,7 @@ __metadata:
   languageName: node
   linkType: hard
 
-"fast-glob@npm:^3.2.11, fast-glob@npm:^3.2.2, fast-glob@npm:^3.2.9, fast-glob@npm:^3.3.2, fast-glob@npm:^3.3.3":
+"fast-glob@npm:^3.2.11, fast-glob@npm:^3.2.2, fast-glob@npm:^3.2.9, fast-glob@npm:^3.3.3":
   version: 3.3.3
   resolution: "fast-glob@npm:3.3.3"
   dependencies: