syntax_data: {"ast_node_type":"other","tokens":[{"end":51,"kind":"keyword","start":0,"text":"impl_span:"}]}
source_snippet:         impl_span: tcx.def_span(local_impl_def_id),
context_before:     let mut diag = tcx.dcx().create_err(NegativePositiveConflict {
context_after:         trait_desc: overlap.trait_ref,