syntax_data: {"ast_node_type":"other","tokens":[{"end":35,"kind":"keyword","start":0,"text":"tcx.def_span(item),"}]}
source_snippet:                 tcx.def_span(item),
context_before:             span_bug!(
context_after:                 "{kind:?} has not seen any uses of `walk_types` yet, ping oli-obk if you'd like any help"