syntax_data: {"ast_node_type":"variable","tokens":[{"end":89,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:                 let (&variant_index, fields) = cv.unwrap_branch().split_first().unwrap();
context_before:             ty::Adt(adt_def, args) if adt_def.is_enum() => {
context_after:                 let variant_index = VariantIdx::from_u32(variant_index.unwrap_leaf().to_u32());