import { describe, it, expect, beforeEach, jest } from '@jest/globals';
import * as path from 'path';
import { FileWatcher } from '../../src/watcher/FileWatcher.js';
import { FileChange } from '../../src/watcher/types.js';
describe('FileWatcher', () => {
jest.useFakeTimers();
const root = process.cwd();
let onBatch: jest.Mock<(changes: FileChange[]) => Promise<void>>;
let watcher: FileWatcher;
beforeEach(() => {
onBatch = jest.fn<(changes: FileChange[]) => Promise<void>>().mockResolvedValue(undefined);
watcher = new FileWatcher(root, { onBatch }, { debounceMs: 50, maxBatchSize: 10 });
});
it('debounces and batches file changes', async () => {
watcher.handleEvent('add', path.join(root, 'a.ts'));
watcher.handleEvent('change', path.join(root, 'a.ts')); // should replace add with change
watcher.handleEvent('add', path.join(root, 'b.ts'));
jest.advanceTimersByTime(60);
await Promise.resolve();
expect(onBatch).toHaveBeenCalledTimes(1);
const batch = onBatch.mock.calls[0][0] as FileChange[];
expect(batch).toHaveLength(2);
const aChange = batch.find((c) => c.path === 'a.ts');
expect(aChange?.type).toBe('change');
});
it('splits batches when exceeding maxBatchSize', async () => {
const paths = Array.from({ length: 12 }, (_, i) => path.join(root, `file${i}.ts`));
paths.forEach((p) => watcher.handleEvent('change', p));
jest.advanceTimersByTime(60);
await Promise.resolve();
expect(onBatch).toHaveBeenCalledTimes(2); // 12 files with batch size 10 -> 2 batches
});
});
