syntax_data: {"ast_node_type":"other","tokens":[{"end":46,"kind":"keyword","start":0,"text":"self.default_mode_span"}]}
source_snippet:         self.default_mode_span = old_mode_span
context_before:     pub(super) fn leave_ref(&mut self, old_mode_span: Option<(Span, Mutability)>) {
context_after:     }