{"ast_node_type":"variable","tokens":[{"end":55,"kind":"keyword","start":0,"text":"let"}]}
            let potential_lock_type = match ty.kind() {
            // Lint for patterns like `mutex.lock()`, which returns `Result<MutexGuard, _>` as well.
                ty::Adt(adt, args) if cx.tcx.is_diagnostic_item(sym::Result, adt.did()) => {