Add support for an additional exclusion file besides .gitignore and .geminiignore (#16487)

Co-authored-by: Adam Weidman <adamfweidman@google.com>

packages/core/src/tools/ripGrep.ts

@@ -23,7 +23,7 @@ import {
   FileExclusions,
   COMMON_DIRECTORY_EXCLUDES,
 } from '../utils/ignorePatterns.js';
-import { GeminiIgnoreParser } from '../utils/geminiIgnoreParser.js';
+import { FileDiscoveryService } from '../services/fileDiscoveryService.js';
 import { execStreaming } from '../utils/shell-utils.js';
 import {
   DEFAULT_TOTAL_MAX_MATCHES,
@@ -148,7 +148,7 @@ class GrepToolInvocation extends BaseToolInvocation<
 > {
   constructor(
     private readonly config: Config,
-    private readonly geminiIgnoreParser: GeminiIgnoreParser,
+    private readonly fileDiscoveryService: FileDiscoveryService,
     params: RipGrepToolParams,
     messageBus: MessageBus,
     _toolName?: string,
@@ -243,6 +243,21 @@ class GrepToolInvocation extends BaseToolInvocation<
         signal.removeEventListener('abort', onAbort);
       }
 
+      if (!this.params.no_ignore) {
+        const uniqueFiles = Array.from(
+          new Set(allMatches.map((m) => m.filePath)),
+        );
+        const absoluteFilePaths = uniqueFiles.map((f) =>
+          path.resolve(searchDirAbs, f),
+        );
+        const allowedFiles =
+          this.fileDiscoveryService.filterFiles(absoluteFilePaths);
+        const allowedSet = new Set(allowedFiles);
+        allMatches = allMatches.filter((m) =>
+          allowedSet.has(path.resolve(searchDirAbs, m.filePath)),
+        );
+      }
+
       const searchLocationDescription = `in path "${searchDirDisplay}"`;
       if (allMatches.length === 0) {
         const noMatchMsg = `No matches found for pattern "${this.params.pattern}" ${searchLocationDescription}${this.params.include ? ` (filter: "${this.params.include}")` : ''}.`;
@@ -361,12 +376,11 @@ class GrepToolInvocation extends BaseToolInvocation<
         rgArgs.push('--glob', `!${exclude}`);
       });
 
-      if (this.config.getFileFilteringRespectGeminiIgnore()) {
-        // Add .geminiignore support (ripgrep natively handles .gitignore)
-        const geminiIgnorePath = this.geminiIgnoreParser.getIgnoreFilePath();
-        if (geminiIgnorePath) {
-          rgArgs.push('--ignore-file', geminiIgnorePath);
-        }
+      // Add .geminiignore and custom ignore files support (if provided/mandated)
+      // (ripgrep natively handles .gitignore)
+      const geminiIgnorePaths = this.fileDiscoveryService.getIgnoreFilePaths();
+      for (const ignorePath of geminiIgnorePaths) {
+        rgArgs.push('--ignore-file', ignorePath);
       }
     }
 
@@ -472,7 +486,7 @@ export class RipGrepTool extends BaseDeclarativeTool<
   ToolResult
 > {
   static readonly Name = GREP_TOOL_NAME;
-  private readonly geminiIgnoreParser: GeminiIgnoreParser;
+  private readonly fileDiscoveryService: FileDiscoveryService;
 
   constructor(
     private readonly config: Config,
@@ -538,7 +552,10 @@ export class RipGrepTool extends BaseDeclarativeTool<
       true, // isOutputMarkdown
       false, // canUpdateOutput
     );
-    this.geminiIgnoreParser = new GeminiIgnoreParser(config.getTargetDir());
+    this.fileDiscoveryService = new FileDiscoveryService(
+      config.getTargetDir(),
+      config.getFileFilteringOptions(),
+    );
   }
 
   /**
@@ -591,7 +608,7 @@ export class RipGrepTool extends BaseDeclarativeTool<
   ): ToolInvocation<RipGrepToolParams, ToolResult> {
     return new GrepToolInvocation(
       this.config,
-      this.geminiIgnoreParser,
+      this.fileDiscoveryService,
       params,
       messageBus ?? this.messageBus,
       _toolName,