syntax_data: {"ast_node_type":"other","tokens":[{"end":83,"kind":"keyword","start":0,"text":")"}]}
source_snippet:     ) -> Result<(PatCtxt<'p, 'tcx>, UsefulnessReport<'p, 'tcx>), ErrorGuaranteed> {
context_before:         scrut: Option<&Expr<'tcx>>,
context_after:         let cx = self.new_cx(refutability, None, scrut, pat.span);