syntax_data: {"ast_node_type":"other","tokens":[{"end":96,"kind":"keyword","start":0,"text":".emit_err(RequiresAnArgument"}]}
source_snippet:                 .emit_err(RequiresAnArgument { span: attr.span(), name: attr.name().unwrap() });
context_before:             tcx.dcx()
context_after:             Err(())