syntax_data: {"ast_node_type":"other","tokens":[{"end":98,"kind":"keyword","start":0,"text":"self.local_expn_data[expn_id].as_ref().expect(\"no"}]}
source_snippet:             self.local_expn_data[expn_id].as_ref().expect("no expansion data for an expansion ID")
context_before:         if let Some(expn_id) = expn_id.as_local() {
context_after:         } else {