syntax_data: {"ast_node_type":"other","tokens":[{"end":92,"kind":"keyword","start":0,"text":"self.equate_trait_refs(obligation.with(tcx,"}]}
source_snippet:             self.equate_trait_refs(obligation.with(tcx, placeholder_predicate), trait_ref)?;
context_before:         let mut nested =
context_after:         let cause = obligation.derived_cause(ObligationCauseCode::BuiltinDerived);