{"ast_node_type":"other","tokens":[{"end":47,"kind":"keyword","start":0,"text":"diagnostic_msg,"}]}
                                diagnostic_msg,
                                closure_body_span.with_lo(closure_body_span.lo() + BytePos::from_usize(line1.len())).shrink_to_lo(),
                                format!("\n{indent}{migration_string};"),