syntax_data: {"ast_node_type":"other","tokens":[{"end":63,"kind":"keyword","start":0,"text":"debug!(\"sanity_check_via_rustc_peek"}]}
source_snippet:     debug!("sanity_check_via_rustc_peek def_id: {:?}", def_id);
context_before:     let def_id = cursor.body().source.def_id();