void _onBatch()

in lib/src/directory_watcher/mac_os.dart [113:178]
51 lines of code
13 McCabe index (conditional complexity)

  void _onBatch(List<FileSystemEvent> batch) {
    // If we get a batch of events before we're ready to begin emitting events,
    // it's probable that it's a batch of pre-watcher events (see issue 14373).
    // Ignore those events and re-list the directory.
    if (!isReady) {
      // Cancel the timer because bogus events only occur in the first batch, so
      // we can fire [ready] as soon as we're done listing the directory.
      _bogusEventTimer.cancel();
      _listDir().then((_) {
        if (!isReady) {
          _readyCompleter.complete();
        }
      });
      return;
    }

    _sortEvents(batch).forEach((path, eventSet) {
      var canonicalEvent = _canonicalEvent(eventSet);
      var events = canonicalEvent == null
          ? _eventsBasedOnFileSystem(path)
          : [canonicalEvent];

      for (var event in events) {
        if (event is FileSystemCreateEvent) {
          if (!event.isDirectory) {
            // If we already know about the file, treat it like a modification.
            // This can happen if a file is copied on top of an existing one.
            // We'll see an ADD event for the latter file when from the user's
            // perspective, the file's contents just changed.
            var type =
                _files.contains(path) ? ChangeType.MODIFY : ChangeType.ADD;

            _emitEvent(type, path);
            _files.add(path);
            continue;
          }

          if (_files.containsDir(path)) continue;

          var stream = Directory(path).list(recursive: true);
          var subscription = stream.listen((entity) {
            if (entity is Directory) return;
            if (_files.contains(path)) return;

            _emitEvent(ChangeType.ADD, entity.path);
            _files.add(entity.path);
          }, cancelOnError: true);
          subscription.onDone(() {
            _listSubscriptions.remove(subscription);
          });
          subscription.onError((Object e, StackTrace stackTrace) {
            _emitError(e, stackTrace);
          });
          _listSubscriptions.add(subscription);
        } else if (event is FileSystemModifyEvent) {
          assert(!event.isDirectory);
          _emitEvent(ChangeType.MODIFY, path);
        } else {
          assert(event is FileSystemDeleteEvent);
          for (var removedPath in _files.remove(path)) {
            _emitEvent(ChangeType.REMOVE, removedPath);
          }
        }
      }
    });
  }