syntax_data: {"ast_node_type":"other","tokens":[{"end":63,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:                     // new error args for the missing generics.
context_before:                     // If this is an ill-formed auto trait, then synthesize
context_after:                     let err_args = GenericArgs::extend_with_error(cx, did, &[self_ty.into()]);