boolean (@NotNull VirtualFile file) { if (myFilesSet == null) { if (myType == CUSTOM) { // optimization if (myScope != null) return myScope.contains(file); } if (myType == PROJECT) { //optimization ProjectFileIndex index = ProjectRootManager.getInstance(myProject).getFileIndex(); return index.isInContent(file) && !isFilteredOut(file); } } return getFileSet().contains(file); }