syntax_data: {"ast_node_type":"variable","tokens":[{"end":53,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:                 let ty::Tuple(tys) = ty.kind() else {
context_before:             hir::PatKind::Tuple(pats, ddpos) => {
context_after:                     span_bug!(pat.span, "unexpected type for tuple pattern: {:?}", ty);