Splits proc_macro::Span::source_text into a new feature gate and stabilizes it.
/// Note: The observable result of a macro should only rely on the tokens and
/// not on this source text. The result of this function is a best effort to
/// be used for diagnostics only.
- #[unstable(feature = "proc_macro_span", issue = "54725")]
+ #[stable(feature = "proc_macro_source_text", since = "CURRENT_RUSTC_VERSION")]
pub fn source_text(&self) -> Option<String> {
self.0.source_text()
}