syntax_data: {"ast_node_type":"other","tokens":[{"end":63,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:         // dummy TerminatorKind. Replace it with a proper goto.
context_before:         // There should be an existing terminator with real source info and a
context_after:         // (The dummy is added by `break_scope` and `break_for_else`.)