fix: gitignore handling (#8177)

packages/core/src/utils/geminiIgnoreParser.test.ts

@@ -0,0 +1,70 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { vi, describe, it, expect, beforeEach, afterEach } from 'vitest';
+import { GeminiIgnoreParser } from './geminiIgnoreParser.js';
+import * as fs from 'node:fs/promises';
+import * as path from 'node:path';
+import * as os from 'node:os';
+
+describe('GeminiIgnoreParser', () => {
+  let projectRoot: string;
+
+  async function createTestFile(filePath: string, content = '') {
+    const fullPath = path.join(projectRoot, filePath);
+    await fs.mkdir(path.dirname(fullPath), { recursive: true });
+    await fs.writeFile(fullPath, content);
+  }
+
+  beforeEach(async () => {
+    projectRoot = await fs.mkdtemp(
+      path.join(os.tmpdir(), 'geminiignore-test-'),
+    );
+  });
+
+  afterEach(async () => {
+    await fs.rm(projectRoot, { recursive: true, force: true });
+    vi.restoreAllMocks();
+  });
+
+  describe('when .geminiignore exists', () => {
+    beforeEach(async () => {
+      await createTestFile(
+        '.geminiignore',
+        'ignored.txt\n# A comment\n/ignored_dir/\n',
+      );
+      await createTestFile('ignored.txt', 'ignored');
+      await createTestFile('not_ignored.txt', 'not ignored');
+      await createTestFile(
+        path.join('ignored_dir', 'file.txt'),
+        'in ignored dir',
+      );
+      await createTestFile(
+        path.join('subdir', 'not_ignored.txt'),
+        'not ignored',
+      );
+    });
+
+    it('should ignore files specified in .geminiignore', () => {
+      const parser = new GeminiIgnoreParser(projectRoot);
+      expect(parser.getPatterns()).toEqual(['ignored.txt', '/ignored_dir/']);
+      expect(parser.isIgnored('ignored.txt')).toBe(true);
+      expect(parser.isIgnored('not_ignored.txt')).toBe(false);
+      expect(parser.isIgnored(path.join('ignored_dir', 'file.txt'))).toBe(true);
+      expect(parser.isIgnored(path.join('subdir', 'not_ignored.txt'))).toBe(
+        false,
+      );
+    });
+  });
+
+  describe('when .geminiignore does not exist', () => {
+    it('should not load any patterns and not ignore any files', () => {
+      const parser = new GeminiIgnoreParser(projectRoot);
+      expect(parser.getPatterns()).toEqual([]);
+      expect(parser.isIgnored('any_file.txt')).toBe(false);
+    });
+  });
+});