syntax_data: {"ast_node_type":"other","tokens":[{"end":96,"kind":"keyword","start":0,"text":"user_provided_types.get(expr.hir_id).copied().map(Box::new);"}]}
source_snippet:                                     user_provided_types.get(expr.hir_id).copied().map(Box::new);
context_before:                                 let user_ty =
context_after:                                 debug!("make_mirror_unadjusted: (variant) user_ty={:?}", user_ty);