syntax_data: {"ast_node_type":"other","tokens":[{"end":84,"kind":"keyword","start":0,"text":"ExpnKind::Desugaring(kind)"}]}
source_snippet:             ExpnKind::Desugaring(kind) => format!("desugaring of {}", kind.descr()),
context_before:             ExpnKind::AstPass(kind) => kind.descr().to_string(),
context_after:         }