test: add unit tests for logger utility (#96)

Adds a test file `src/logger.test.ts` to verify that `logger.info`, `logger.warn`, and `logger.error` correctly call the underlying console methods with the passed arguments.

Co-authored-by: google-labs-jules[bot] <161369871+google-labs-jules[bot]@users.noreply.github.com>

src/logger.test.ts

@@ -0,0 +1,30 @@
+import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest';
+import { logger } from './logger';
+
+describe('logger', () => {
+  beforeEach(() => {
+    vi.spyOn(console, 'info').mockImplementation(() => {});
+    vi.spyOn(console, 'warn').mockImplementation(() => {});
+    vi.spyOn(console, 'error').mockImplementation(() => {});
+  });
+
+  afterEach(() => {
+    vi.restoreAllMocks();
+  });
+
+  it('should call console.info with correct arguments', () => {
+    logger.info('test info', { key: 'value' });
+    expect(console.info).toHaveBeenCalledWith('test info', { key: 'value' });
+  });
+
+  it('should call console.warn with correct arguments', () => {
+    logger.warn('test warn', 42);
+    expect(console.warn).toHaveBeenCalledWith('test warn', 42);
+  });
+
+  it('should call console.error with correct arguments', () => {
+    const error = new Error('test error');
+    logger.error('test error message', error);
+    expect(console.error).toHaveBeenCalledWith('test error message', error);
+  });
+});