Comparator<PsiElement> (@NotNull Project project) { FileIndexFacade index = FileIndexFacade.getInstance(project); return Comparator.comparing((PsiElement element) -> { PsiFile containingFile = element.getContainingFile(); if (containingFile != null) { VirtualFile virtualFile = containingFile.getVirtualFile(); if (virtualFile != null && index.isInContent(virtualFile)) return true; } return false; }).reversed(); }