syntax_data: {"ast_node_type":"other","tokens":[{"end":98,"kind":"keyword","start":0,"text":"(MixedBitSet::Large(set),"}]}
source_snippet:             (MixedBitSet::Large(set), MixedBitSet::Large(old)) => set.fmt_diff_with(old, ctxt, f),
context_before:             (MixedBitSet::Small(set), MixedBitSet::Small(old)) => set.fmt_diff_with(old, ctxt, f),
context_after:             _ => panic!("MixedBitSet size mismatch"),