boolean (final PsiElement element, final Project project) { final PsiFile file = element.getContainingFile(); if (file != null && file.getVirtualFile() != null) { final FileIndexFacade indexFacade = FileIndexFacade.getInstance(project); final VirtualFile vf = file.getVirtualFile(); return indexFacade.isInSource(vf) || indexFacade.isInSourceContent(vf); } return false; }