syntax_data: {"ast_node_type":"import","tokens":[{"end":87,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:     // implementation, running this pass may cause otherwise-valid code to not compile.
context_before:     // This pass emits new panics. If for whatever reason we do not have a panic
context_after:     if tcx.lang_items().get(LangItem::PanicImpl).is_none() {