syntax_data: {"ast_node_type":"other","tokens":[{"end":51,"kind":"keyword","start":0,"text":"SafetyContext::BuiltinUnsafeBlock"}]}
source_snippet:             SafetyContext::BuiltinUnsafeBlock => {}
context_before:         match self.safety_context {
context_after:             SafetyContext::UnsafeBlock { ref mut used, .. } => {