Improve the performance of filename completion over large repositories. (#938)

6 files changed, 84 insertions, 11 deletions

diff --git a/eslint.config.js b/eslint.config.js
index 9bf13cde..443bd9ae 100644
--- a/eslint.config.js
+++ b/eslint.config.js
@@ -32,6 +32,7 @@ export default tseslint.config(
       'eslint.config.js',
       'packages/cli/dist/**',
       'packages/core/dist/**',
+      'packages/server/dist/**',
       'eslint-rules/*',
       'bundle/**',
     ],
diff --git a/packages/cli/package.json b/packages/cli/package.json
index 03eca1c7..1e1c86a5 100644
--- a/packages/cli/package.json
+++ b/packages/cli/package.json
@@ -30,6 +30,7 @@
   },
   "dependencies": {
     "@gemini-cli/core": "file:../core",
+    "command-exists": "^1.2.9",
     "diff": "^7.0.0",
     "dotenv": "^16.4.7",
     "highlight.js": "^11.11.1",
@@ -48,18 +49,17 @@
     "string-width": "^7.1.0",
     "strip-ansi": "^7.1.0",
     "strip-json-comments": "^3.1.1",
-    "command-exists": "^1.2.9",
     "yargs": "^17.7.2"
   },
   "devDependencies": {
     "@testing-library/react": "^14.0.0",
+    "@types/command-exists": "^1.2.3",
     "@types/diff": "^7.0.2",
     "@types/dotenv": "^6.1.1",
     "@types/node": "^20.11.24",
     "@types/react": "^18.3.1",
     "@types/shell-quote": "^1.7.5",
     "@types/yargs": "^17.0.32",
-    "@types/command-exists": "^1.2.3",
     "ink-testing-library": "^4.0.0",
     "jsdom": "^26.1.0",
     "typescript": "^5.3.3",
diff --git a/packages/cli/src/ui/hooks/useCompletion.integration.test.ts b/packages/cli/src/ui/hooks/useCompletion.integration.test.ts
index 683d3cb1..c38006c3 100644
--- a/packages/cli/src/ui/hooks/useCompletion.integration.test.ts
+++ b/packages/cli/src/ui/hooks/useCompletion.integration.test.ts
@@ -42,6 +42,7 @@ describe('useCompletion git-aware filtering integration', () => {
       shouldIgnoreFile: vi.fn(),
       filterFiles: vi.fn(),
       getIgnoreInfo: vi.fn(() => ({ gitIgnored: [], customIgnored: [] })),
+      glob: vi.fn().mockResolvedValue([]),
     };
 
     mockConfig = {
@@ -225,4 +226,27 @@ describe('useCompletion git-aware filtering integration', () => {
       { label: 'component.tsx', value: 'component.tsx' },
     ]);
   });
+
+  it('should use glob for top-level @ completions when available', async () => {
+    const globResults = [`${testCwd}/src/index.ts`, `${testCwd}/README.md`];
+    mockFileDiscoveryService.glob.mockResolvedValue(globResults);
+
+    const { result } = renderHook(() =>
+      useCompletion('@s', testCwd, true, slashCommands, mockConfig),
+    );
+
+    await act(async () => {
+      await new Promise((resolve) => setTimeout(resolve, 150));
+    });
+
+    expect(mockFileDiscoveryService.glob).toHaveBeenCalledWith('**/s*', {
+      cwd: testCwd,
+      dot: true,
+    });
+    expect(fs.readdir).not.toHaveBeenCalled(); // Ensure glob is used instead of readdir
+    expect(result.current.suggestions).toEqual([
+      { label: 'README.md', value: 'README.md' },
+      { label: 'src/index.ts', value: 'src/index.ts' },
+    ]);
+  });
 });
diff --git a/packages/cli/src/ui/hooks/useCompletion.ts b/packages/cli/src/ui/hooks/useCompletion.ts
index 66457aac..810c6de0 100644
--- a/packages/cli/src/ui/hooks/useCompletion.ts
+++ b/packages/cli/src/ui/hooks/useCompletion.ts
@@ -13,6 +13,7 @@ import {
   unescapePath,
   getErrorMessage,
   Config,
+  FileDiscoveryService,
 } from '@gemini-cli/core';
 import {
   MAX_SUGGESTIONS_TO_SHOW,
@@ -251,21 +252,53 @@ export function useCompletion(
       return foundSuggestions.slice(0, maxResults);
     };
 
+    const findFilesWithGlob = async (
+      searchPrefix: string,
+      fileDiscoveryService: FileDiscoveryService,
+      maxResults = 50,
+    ): Promise<Suggestion[]> => {
+      const globPattern = `**/${searchPrefix}*`;
+      const files = await fileDiscoveryService.glob(globPattern, {
+        cwd,
+        dot: true,
+      });
+
+      const suggestions: Suggestion[] = files
+        .map((file: string) => {
+          const relativePath = path.relative(cwd, file);
+          return {
+            label: relativePath,
+            value: escapePath(relativePath),
+          };
+        })
+        .slice(0, maxResults);
+
+      return suggestions;
+    };
+
     const fetchSuggestions = async () => {
       setIsLoadingSuggestions(true);
       let fetchedSuggestions: Suggestion[] = [];
 
-      // Get centralized file discovery service if config is available
-      const fileDiscovery = config ? await config.getFileService() : null;
+      const fileDiscoveryService = config
+        ? await config.getFileService()
+        : null;
 
       try {
         // If there's no slash, or it's the root, do a recursive search from cwd
         if (partialPath.indexOf('/') === -1 && prefix) {
-          fetchedSuggestions = await findFilesRecursively(
-            cwd,
-            prefix,
-            fileDiscovery,
-          );
+          if (fileDiscoveryService) {
+            fetchedSuggestions = await findFilesWithGlob(
+              prefix,
+              fileDiscoveryService,
+            );
+          } else {
+            fetchedSuggestions = await findFilesRecursively(
+              cwd,
+              prefix,
+              fileDiscoveryService,
+            );
+          }
         } else {
           // Original behavior: list files in the specific directory
           const lowerPrefix = prefix.toLowerCase();
@@ -282,7 +315,10 @@ export function useCompletion(
               cwd,
               path.join(baseDirAbsolute, entry.name),
             );
-            if (fileDiscovery && fileDiscovery.shouldIgnoreFile(relativePath)) {
+            if (
+              fileDiscoveryService &&
+              fileDiscoveryService.shouldIgnoreFile(relativePath)
+            ) {
               continue;
             }
 
diff --git a/packages/core/src/services/fileDiscoveryService.ts b/packages/core/src/services/fileDiscoveryService.ts
index 3874e752..f117813d 100644
--- a/packages/core/src/services/fileDiscoveryService.ts
+++ b/packages/core/src/services/fileDiscoveryService.ts
@@ -7,6 +7,7 @@
 import { GitIgnoreParser, GitIgnoreFilter } from '../utils/gitIgnoreParser.js';
 import { isGitRepository } from '../utils/gitUtils.js';
 import * as path from 'path';
+import fg from 'fast-glob';
 
 export interface FileDiscoveryOptions {
   respectGitIgnore?: boolean;
@@ -32,6 +33,17 @@ export class FileDiscoveryService {
     }
   }
 
+  async glob(
+    pattern: string | string[],
+    options: fg.Options = {},
+  ): Promise<string[]> {
+    const files = await fg(pattern, {
+      ...options,
+      caseSensitiveMatch: false,
+    });
+    return this.filterFiles(files);
+  }
+
   /**
    * Filters a list of file paths based on git ignore rules
    */
diff --git a/packages/core/src/utils/gitIgnoreParser.ts b/packages/core/src/utils/gitIgnoreParser.ts
index ae1a7a01..d5d013a8 100644
--- a/packages/core/src/utils/gitIgnoreParser.ts
+++ b/packages/core/src/utils/gitIgnoreParser.ts
@@ -6,7 +6,7 @@
 
 import * as fs from 'fs/promises';
 import * as path from 'path';
-import ignore, { Ignore } from 'ignore';
+import ignore, { type Ignore } from 'ignore';
 import { isGitRepository } from './gitUtils.js';
 
 export interface GitIgnoreFilter {