@NotNull
  public static Collection<PsiFileSystemItem> getAbsoluteTopLevelDirLocations(
      final @NotNull PsiFile file) {

    final VirtualFile virtualFile = file.getVirtualFile();
    if (virtualFile == null) {
      return Collections.emptyList();
    }
    final Project project = file.getProject();
    PsiDirectory parent = file.getParent();
    final Module module = ModuleUtil.findModuleForPsiElement(parent == null ? file : parent);
    if (module == null) {
      return Collections.emptyList();
    }
    final FileReferenceHelper[] helpers = FileReferenceHelperRegistrar.getHelpers();
    final ArrayList<PsiFileSystemItem> list = new ArrayList<PsiFileSystemItem>();
    for (FileReferenceHelper helper : helpers) {
      if (helper.isMine(project, virtualFile)) {
        final Collection<PsiFileSystemItem> roots = helper.getRoots(module);
        for (PsiFileSystemItem root : roots) {
          LOG.assertTrue(root != null, "Helper " + helper + " produced a null root for " + file);
        }
        list.addAll(roots);
      }
    }

    if (list.size() == 0) {
      list.addAll(FileReferenceHelperRegistrar.getNotNullHelper(file).getRoots(module));
    }
    return list;
  }
  @NotNull
  private Collection<PsiFileSystemItem> getContextByFile(@NotNull PsiFile file) {
    final PsiElement context = file.getContext();
    if (context != null) file = context.getContainingFile();

    if (useIncludingFileAsContext()) {
      final FileContextProvider contextProvider = FileContextProvider.getProvider(file);
      if (contextProvider != null) {
        final Collection<PsiFileSystemItem> folders = contextProvider.getContextFolders(file);
        if (!folders.isEmpty()) {
          return folders;
        }
        final PsiFile contextFile = contextProvider.getContextFile(file);
        if (contextFile != null) {
          return Collections.<PsiFileSystemItem>singleton(contextFile.getParent());
        }
      }
    }

    VirtualFile virtualFile = file.getOriginalFile().getVirtualFile();

    if (virtualFile != null) {
      final FileReferenceHelper[] helpers = FileReferenceHelperRegistrar.getHelpers();
      final ArrayList<PsiFileSystemItem> list = new ArrayList<PsiFileSystemItem>();
      final Project project = file.getProject();
      for (FileReferenceHelper helper : helpers) {
        if (helper.isMine(project, virtualFile)) {
          list.addAll(helper.getContexts(project, virtualFile));
        }
      }
      if (list.size() > 0) {
        return list;
      }
      final VirtualFile parent = virtualFile.getParent();
      if (parent != null) {
        final PsiDirectory directory = file.getManager().findDirectory(parent);
        if (directory != null) {
          return Collections.<PsiFileSystemItem>singleton(directory);
        }
      }
    }
    return Collections.emptyList();
  }