syntax_data: {"ast_node_type":"variable","tokens":[{"end":81,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:         let mut checker = ConstMutationChecker { body, tcx, target_local: None };
context_before:     fn run_lint(&self, tcx: TyCtxt<'tcx>, body: &Body<'tcx>) {
context_after:         checker.visit_body(body);