Function doWatchTest

test/parallel/test-fs-watch.js:44–82

(testCase)

tmpdir.refresh();

function doWatchTest(testCase) {
  let interval;
  const pathToWatch = testCase[testCase.field];
  const watcher = fs.watch(pathToWatch);
  watcher.on('error', (err) => {
    if (interval) {
      clearInterval(interval);
      interval = null;
    }
    assert.fail(err);
  });
  watcher.on('close', common.mustCall(() => {
    watcher.close(); // Closing a closed watcher should be a noop
  }));
  watcher.on('change', common.mustCall(function(eventType, argFilename) {
    if (interval) {
      clearInterval(interval);
      interval = null;
    }
    if (common.isMacOS)
      assert.strictEqual(['rename', 'change'].includes(eventType), true);
    else
      assert.strictEqual(eventType, 'change');
    assert.strictEqual(argFilename, testCase.fileName);

    watcher.close();

    // We document that watchers cannot be used anymore when it's closed,
    // here we turn the methods into noops instead of throwing
    watcher.close(); // Closing a closed watcher should be a noop
  }));

  // Long content so it's actually flushed. toUpperCase so there's real change.
  const content2 = Date.now() + testCase.fileName.toUpperCase().repeat(1e4);
  interval = setInterval(() => {
    fs.writeFileSync(testCase.filePath, '');
    fs.writeFileSync(testCase.filePath, content2);
  }, 100);
}

for (const testCase of cases) {
  if (testCase.shouldSkip) continue;