From fb7a8294f898652482e4b4106143fac294d7af0d Mon Sep 17 00:00:00 2001 From: Jonas Schievink Date: Sat, 15 Oct 2016 02:56:29 +0200 Subject: [PATCH] proc_macro_plugin: Wrap nonexistent filename in <> I'm not sure how big of an issue this can become in practice, but `FileMap`s made from something that's not a file are supposed to wrap the file name in `<>`. For an example fix, see kevinmehall/rust-peg@332fd4dbae19b64fb2af4b9d565e37a3703e7576. There, it caused cargo to always recompile a crate using rust-peg, even when nothing was changed, because cargo sees that the dummy file doesn't exist. --- src/libproc_macro_tokens/parse.rs | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/src/libproc_macro_tokens/parse.rs b/src/libproc_macro_tokens/parse.rs index 9af8a68cdcf49..5ab4fcd5dab29 100644 --- a/src/libproc_macro_tokens/parse.rs +++ b/src/libproc_macro_tokens/parse.rs @@ -15,12 +15,12 @@ extern crate syntax; use syntax::parse::{ParseSess, filemap_to_tts}; use syntax::tokenstream::TokenStream; -/// Map a string to tts, using a made-up filename. For example, `lex(15)` will return a +/// Map a string to tts, using a made-up filename. For example, `lex("15")` will return a /// TokenStream containing the literal 15. pub fn lex(source_str: &str) -> TokenStream { let ps = ParseSess::new(); TokenStream::from_tts(filemap_to_tts(&ps, - ps.codemap().new_filemap("procmacro_lex".to_string(), + ps.codemap().new_filemap("".to_string(), None, source_str.to_owned()))) }