syntax_data: {"ast_node_type":"other","tokens":[{"end":57,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:         // HACK(eddyb) Avoid having RustCall on closures,
context_before:     if let DefKind::Closure = tcx.def_kind(fn_def) {
context_after:         // as it adds unnecessary (and wrong) auto-tupling.