syntax_data: {"ast_node_type":"other","tokens":[{"end":13,"kind":"keyword","start":0,"text":"{"}]}
source_snippet:             {
context_before:             if matches!(coroutine_kind, CoroutineKind::Desugared(CoroutineDesugaring::AsyncGen, _))
context_after:                 // For AsyncGen we need `yield Poll<OptRet>::Pending`