feat(core): share file list patterns between glob and grep tools (#6359)

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>
Co-authored-by: Arya Gummadi <aryagummadi@google.com>

packages/core/src/tools/grep.ts

@@ -21,6 +21,7 @@ import { makeRelative, shortenPath } from '../utils/paths.js';
 import { getErrorMessage, isNodeError } from '../utils/errors.js';
 import { isGitRepository } from '../utils/gitUtils.js';
 import { Config } from '../config/config.js';
+import { FileExclusions } from '../utils/ignorePatterns.js';
 import { ToolErrorType } from './tool-error.js';
 
 // --- Interfaces ---
@@ -58,11 +59,14 @@ class GrepToolInvocation extends BaseToolInvocation<
   GrepToolParams,
   ToolResult
 > {
+  private readonly fileExclusions: FileExclusions;
+
   constructor(
     private readonly config: Config,
     params: GrepToolParams,
   ) {
     super(params);
+    this.fileExclusions = config.getFileExclusions();
   }
 
   /**
@@ -281,7 +285,6 @@ class GrepToolInvocation extends BaseToolInvocation<
 
   /**
    * Gets a description of the grep operation
-   * @param params Parameters for the grep operation
    * @returns A string describing the grep
    */
   getDescription(): string {
@@ -391,7 +394,27 @@ class GrepToolInvocation extends BaseToolInvocation<
       if (grepAvailable) {
         strategyUsed = 'system grep';
         const grepArgs = ['-r', '-n', '-H', '-E'];
-        const commonExcludes = ['.git', 'node_modules', 'bower_components'];
+        // Extract directory names from exclusion patterns for grep --exclude-dir
+        const globExcludes = this.fileExclusions.getGlobExcludes();
+        const commonExcludes = globExcludes
+          .map((pattern) => {
+            let dir = pattern;
+            if (dir.startsWith('**/')) {
+              dir = dir.substring(3);
+            }
+            if (dir.endsWith('/**')) {
+              dir = dir.slice(0, -3);
+            } else if (dir.endsWith('/')) {
+              dir = dir.slice(0, -1);
+            }
+
+            // Only consider patterns that are likely directories. This filters out file patterns.
+            if (dir && !dir.includes('/') && !dir.includes('*')) {
+              return dir;
+            }
+            return null;
+          })
+          .filter((dir): dir is string => !!dir);
         commonExcludes.forEach((dir) => grepArgs.push(`--exclude-dir=${dir}`));
         if (include) {
           grepArgs.push(`--include=${include}`);
@@ -474,13 +497,7 @@ class GrepToolInvocation extends BaseToolInvocation<
       );
       strategyUsed = 'javascript fallback';
       const globPattern = include ? include : '**/*';
-      const ignorePatterns = [
-        '.git/**',
-        'node_modules/**',
-        'bower_components/**',
-        '.svn/**',
-        '.hg/**',
-      ]; // Use glob patterns for ignores here
+      const ignorePatterns = this.fileExclusions.getGlobExcludes();
 
       const filesStream = globStream(globPattern, {
         cwd: absolutePath,