syntax_data: {"ast_node_type":"other","tokens":[{"end":18,"kind":"keyword","start":0,"text":"};"}]}
source_snippet:                 };
context_before:                     (ONE, IndexVec::from_raw(vec![val])) // Some(val)
context_after:                 make_aggregate_adt(option_def_id, variant_idx, args, operands)