syntax_data: {"ast_node_type":"other","tokens":[{"end":50,"kind":"keyword","start":0,"text":"Some(Ty::new_generic_adt(tcx,"}]}
source_snippet:         Some(Ty::new_generic_adt(tcx, def_id, ty))
context_before:         let def_id = tcx.get_diagnostic_item(name)?;
context_after:     }