syntax_data: {"ast_node_type":"other","tokens":[{"end":82,"kind":"keyword","start":0,"text":"VarianceDiagInfo::Invariant"}]}
source_snippet:             VarianceDiagInfo::Invariant { ty, param_index: i.try_into().unwrap() }
context_before:             let ty = *cached_ty.get_or_insert_with(|| cx.type_of(ty_def_id).instantiate(cx, a_arg));
context_after:         } else {