Add support for repetition to proc_macro::quote
#141608
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moatom
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proc_macro::quoteproc_macro::quote
| @@ -1613,3 +1614,202 @@ pub mod tracked_path { | |||
| crate::bridge::client::FreeFunctions::track_path(path); | |||
| } | |||
| } | |||
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| #[doc(hidden)] | |||
| #[unstable(feature = "proc_macro_quote", issue = "54722")] | |||
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I am not sure whether these annotations are appropriate. (I added them just based on my speculation.)
In addition,
It's probably easiest to just copy quote's logic here, which uses an extension trait to facilitate this.
do we need to take care of its license?
| #[unstable(feature = "proc_macro_quote", issue = "54722")] | ||
| pub mod ext { | ||
| use core::slice; | ||
| use std::collections::btree_set::{self, BTreeSet}; |
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an alternative for alloc::collections
| } | ||
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| self.tokens[self.pos] = self.iter.next(); | ||
| let token_opt = self.tokens[self.pos].clone(); |
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This helper struct may require significant refactoring. (Especially, the use of .clone() might be avoidable.)
Do you have any comments or suggestions?
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Might be worth using just a Peekable. I think it would be better to use it at the expense of some extra parsing code, than using a custom lookahead iterator
| @@ -71,10 +160,97 @@ pub fn quote(stream: TokenStream) -> TokenStream { | |||
| let mut after_dollar = false; | |||
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| let mut tokens = crate::TokenStream::new(); | |||
| for tree in stream { | |||
| let mut iter = LookaheadIter::new(stream); | |||
| while let Some(tree) = iter.next() { | |||
| if after_dollar { | |||
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after_dollar can be combined with LookaheadIter, if you prefer.
| assert_eq!("X, X, X, X,", quote!($($primes,)*).to_string()); | ||
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| assert_eq!("X, X, X, X", quote!($($primes),*).to_string()); |
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I adjusted the expected spacing around SEP in the original test code. Is it appropriate?
Cf. https://github.com/dtolnay/quote/blob/62fd385a800f7398ab416c00100664479261a86e/tests/test.rs#L84
| // FIXME(quote): `proc_macro::quote!` doesn't support repetition at the moment, so the stderr is | ||
| // expected to be incorrect. | ||
| //@ known-bug: #54722 | ||
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Is it sufficient to simply remove these, or is some additional workaround needed?
E.g.:
//@ check-pass
//@ force-host
//@ no-prefer-dynamic
//@ compile-flags: -Z unpretty=expanded
//@ needs-unwind compiling proc macros with panic=abort causes a warning
//@ edition: 2015There was a problem hiding this comment.
plus any new tests in tests/ui/proc-macro/quote for things we should reject
Do you have any examples besides these?
Fixed #140238
ToDo