syntax_data: {"ast_node_type":"other","tokens":[{"end":78,"kind":"keyword","start":0,"text":"if"}]}
source_snippet:         if tcx.is_coroutine(owner_def.to_def_id()) && body.params.is_empty() {
context_before:         // It will always be `()` in this case.
context_after:             cx.thir.params.push(Param {