test/parallel/test-fs-watch-recursive-sync-write.js

'use strict';

const common = require('../common');
const { watch, writeFileSync } = require('node:fs');
const { join } = require('node:path');
const tmpdir = require('../common/tmpdir.js');
const assert = require('assert');

if (common.isIBMi)
  common.skip('IBMi does not support `fs.watch()`');

// fs-watch on folders have limited capability in AIX.
// The testcase makes use of folder watching, and causes
// hang. This behavior is documented. Skip this for AIX.

if (common.isAIX)
  common.skip('folder watch capability is limited in AIX.');

tmpdir.refresh();

const tmpDir = tmpdir.path;
const filename = join(tmpDir, 'test.file');

const keepalive = setTimeout(() => {
  throw new Error('timed out');
}, common.platformTimeout(30_000));

function doWatch() {
  const watcher = watch(tmpDir, { recursive: true }, common.mustCall((eventType, _filename) => {
    clearTimeout(keepalive);
    watcher.close();
    assert.strictEqual(eventType, 'rename');
    assert.strictEqual(join(tmpDir, _filename), filename);
  }));

  // Do the write with a delay to ensure that the OS is ready to notify us.
  setTimeout(() => {
    writeFileSync(filename, 'foobar2');
  }, common.platformTimeout(200));
}

if (common.isMacOS) {
  // On macOS delay watcher start to avoid leaking previous events.
  // Refs: https://github.com/libuv/libuv/pull/4503
  setTimeout(doWatch, common.platformTimeout(100));
} else {
  doWatch();
}