boolean resetOnEvents(@NotNull List<? extends VFileEvent> events) {
   for (VFileEvent event : events) {
     VirtualFile file = event.getFile();
     if (file == null || file.isDirectory()) {
       return true;
     }
   }
   return false;
 }
  private void assertEvent(Class<? extends VFileEvent> type, String... paths) {
    List<VFileEvent> events = getEvents(type.getSimpleName(), null);
    assertEquals(events.toString(), paths.length, events.size());

    Set<String> pathSet =
        ContainerUtil.map2Set(
            paths,
            new Function<String, String>() {
              @Override
              public String fun(final String path) {
                return FileUtil.toSystemIndependentName(path);
              }
            });

    for (VFileEvent event : events) {
      assertTrue(event.toString(), type.isInstance(event));
      VirtualFile eventFile = event.getFile();
      assertNotNull(event.toString(), eventFile);
      assertTrue(
          eventFile + " not in " + Arrays.toString(paths), pathSet.remove(eventFile.getPath()));
    }
  }
  @Override
  public void after(@NotNull List<? extends VFileEvent> events) {
    // which files in .git were changed
    boolean configChanged = false;
    boolean headChanged = false;
    boolean branchFileChanged = false;
    boolean packedRefsChanged = false;
    boolean rebaseFileChanged = false;
    boolean mergeFileChanged = false;
    for (VFileEvent event : events) {
      final VirtualFile file = event.getFile();
      if (file == null) {
        continue;
      }
      String filePath = GitFileUtils.stripFileProtocolPrefix(file.getPath());
      if (myRepositoryFiles.isConfigFile(filePath)) {
        configChanged = true;
      } else if (myRepositoryFiles.isHeadFile(filePath)) {
        headChanged = true;
      } else if (myRepositoryFiles.isBranchFile(filePath)) {
        // it is also possible, that a local branch with complex name ("myfolder/mybranch") was
        // created => the folder also to be watched.
        branchFileChanged = true;
        visitAllChildrenRecursively(myHeadsDir);
      } else if (myRepositoryFiles.isRemoteBranchFile(filePath)) {
        // it is possible, that a branch from a new remote was fetch => we need to add new remote
        // folder to the VFS
        branchFileChanged = true;
        visitAllChildrenRecursively(myRemotesDir);
      } else if (myRepositoryFiles.isPackedRefs(filePath)) {
        packedRefsChanged = true;
      } else if (myRepositoryFiles.isRebaseFile(filePath)) {
        rebaseFileChanged = true;
      } else if (myRepositoryFiles.isMergeFile(filePath)) {
        mergeFileChanged = true;
      }
    }

    // what should be updated in GitRepository
    boolean updateCurrentBranch = false;
    boolean updateCurrentRevision = false;
    boolean updateState = false;
    boolean updateBranches = false;
    if (headChanged) {
      updateCurrentBranch = true;
      updateCurrentRevision = true;
      updateState = true;
    }
    if (branchFileChanged) {
      updateCurrentRevision = true;
      updateBranches = true;
    }
    if (rebaseFileChanged || mergeFileChanged) {
      updateState = true;
    }
    if (packedRefsChanged) {
      updateCurrentBranch = true;
      updateBranches = true;
    }

    // update GitRepository on pooled thread, because it requires reading from disk and parsing
    // data.
    if (updateCurrentBranch) {
      myUpdateQueue.add(GitRepository.TrackedTopic.CURRENT_BRANCH);
    }
    if (updateCurrentRevision) {
      myUpdateQueue.add(GitRepository.TrackedTopic.CURRENT_REVISION);
    }
    if (updateState) {
      myUpdateQueue.add(GitRepository.TrackedTopic.STATE);
    }
    if (updateBranches) {
      myUpdateQueue.add(GitRepository.TrackedTopic.BRANCHES);
    }
    if (configChanged) {
      myUpdateQueue.add(GitRepository.TrackedTopic.CONFIG);
    }
  }