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

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' },
+    ]);
+  });
 });

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;
             }