void (@NotNull VirtualFile dir, @NotNull List<? super VirtualFile> filesList) { for (VirtualFile child : myDirectory2Children.getOrDefault(dir, Collections.emptyList())) { ProgressManager.checkCanceled(); if (!child.isDirectory()) { if (LOG.isDebugEnabled()) { LOG.assertTrue(!filesList.contains(child)); } filesList.add(child); } else { collectFiles(child, filesList); } } }