feat(core, cli): Introduce high-performance FileSearch engine (#5136)

Co-authored-by: Jacob Richman <[email protected]>

1 files changed, 112 insertions, 0 deletions

diff --git a/packages/core/src/utils/filesearch/crawlCache.test.ts b/packages/core/src/utils/filesearch/crawlCache.test.ts
new file mode 100644
index 00000000..2feab61a
--- /dev/null
+++ b/packages/core/src/utils/filesearch/crawlCache.test.ts
@@ -0,0 +1,112 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { describe, it, expect, vi, afterEach, beforeEach } from 'vitest';
+import { getCacheKey, read, write, clear } from './crawlCache.js';
+
+describe('CrawlCache', () => {
+  describe('getCacheKey', () => {
+    it('should generate a consistent hash', () => {
+      const key1 = getCacheKey('/foo', 'bar');
+      const key2 = getCacheKey('/foo', 'bar');
+      expect(key1).toBe(key2);
+    });
+
+    it('should generate a different hash for different directories', () => {
+      const key1 = getCacheKey('/foo', 'bar');
+      const key2 = getCacheKey('/bar', 'bar');
+      expect(key1).not.toBe(key2);
+    });
+
+    it('should generate a different hash for different ignore content', () => {
+      const key1 = getCacheKey('/foo', 'bar');
+      const key2 = getCacheKey('/foo', 'baz');
+      expect(key1).not.toBe(key2);
+    });
+  });
+
+  describe('in-memory cache operations', () => {
+    beforeEach(() => {
+      // Ensure a clean slate before each test
+      clear();
+    });
+
+    afterEach(() => {
+      // Restore real timers after each test that uses fake ones
+      vi.useRealTimers();
+    });
+
+    it('should write and read data from the cache', () => {
+      const key = 'test-key';
+      const data = ['foo', 'bar'];
+      write(key, data, 10000); // 10 second TTL
+      const cachedData = read(key);
+      expect(cachedData).toEqual(data);
+    });
+
+    it('should return undefined for a nonexistent key', () => {
+      const cachedData = read('nonexistent-key');
+      expect(cachedData).toBeUndefined();
+    });
+
+    it('should clear the cache', () => {
+      const key = 'test-key';
+      const data = ['foo', 'bar'];
+      write(key, data, 10000);
+      clear();
+      const cachedData = read(key);
+      expect(cachedData).toBeUndefined();
+    });
+
+    it('should automatically evict a cache entry after its TTL expires', async () => {
+      vi.useFakeTimers();
+      const key = 'ttl-key';
+      const data = ['foo'];
+      const ttl = 5000; // 5 seconds
+
+      write(key, data, ttl);
+
+      // Should exist immediately after writing
+      expect(read(key)).toEqual(data);
+
+      // Advance time just before expiration
+      await vi.advanceTimersByTimeAsync(ttl - 1);
+      expect(read(key)).toEqual(data);
+
+      // Advance time past expiration
+      await vi.advanceTimersByTimeAsync(1);
+      expect(read(key)).toBeUndefined();
+    });
+
+    it('should reset the timer when an entry is updated', async () => {
+      vi.useFakeTimers();
+      const key = 'update-key';
+      const initialData = ['initial'];
+      const updatedData = ['updated'];
+      const ttl = 5000; // 5 seconds
+
+      // Write initial data
+      write(key, initialData, ttl);
+
+      // Advance time, but not enough to expire
+      await vi.advanceTimersByTimeAsync(3000);
+      expect(read(key)).toEqual(initialData);
+
+      // Update the data, which should reset the timer
+      write(key, updatedData, ttl);
+      expect(read(key)).toEqual(updatedData);
+
+      // Advance time again. If the timer wasn't reset, the total elapsed
+      // time (3000 + 3000 = 6000) would cause an eviction.
+      await vi.advanceTimersByTimeAsync(3000);
+      expect(read(key)).toEqual(updatedData);
+
+      // Advance past the new expiration time
+      await vi.advanceTimersByTimeAsync(2001);
+      expect(read(key)).toBeUndefined();
+    });
+  });
+});