syntax_data: {"ast_node_type":"function","tokens":[{"end":80,"kind":"keyword","start":0,"text":"fn"}]}
source_snippet:     fn into_diag_arg(self, _: &mut Option<std::path::PathBuf>) -> DiagArgValue {
context_before: impl IntoDiagArg for CrateType {
context_after:         self.to_string().into_diag_arg(&mut None)