rust - https://github.com/rust-lang/rust

Age	Commit message (Collapse)	Author	Lines
2020-06-08	Show `SyntaxContext` in formatted `Span` debug output	Aaron Hill	-30/+30
	This is only really useful in debug messages, so I've switched to calling `span_to_string` in any place that causes a `Span` to end up in user-visible output.
2020-06-04	Add `-Z span-debug` to allow for easier debugging of proc macros	Aaron Hill	-0/+166
	Currently, the `Debug` impl for `proc_macro::Span` just prints out the byte range. This can make debugging proc macros (either as a crate author or as a compiler developer) very frustrating, since neither the actual filename nor the `SyntaxContext` is displayed. This commit adds a perma-unstable flag `-Z span-debug`. When enabled, the `Debug` impl for `proc_macro::Span` simply forwards directly to `rustc_span::Span`. Once #72618 is merged, this will start displaying actual line numbers. While `Debug` impls are not subject to Rust's normal stability guarnatees, we probably shouldn't expose any additional information on stable until `#![feature(proc_macro_span)]` is stabilized. Otherwise, we would be providing a 'backdoor' way to access information that's supposed be behind unstable APIs.