{"ast_node_type":"variable","tokens":[{"end":79,"kind":"keyword","start":0,"text":"let"}]}
        let current_crate = crates_for(self.db, file_id).pop().map(Into::into);
    fn add_file(&mut self, file_id: FileId) {
        let folds = self.analysis.folding_ranges(file_id).unwrap();