syntax_data: {"ast_node_type":"variable","tokens":[{"end":33,"kind":"keyword","start":0,"text":"if"}]}
source_snippet:             if let Err(e) = res {
context_before:             let res = write_graphviz_results(tcx, body, &mut self, &results, pass_name);
context_after:                 error!("Failed to write graphviz dataflow results: {}", e);