Remove span in generated field getter#3725
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Liamolucko merged 4 commits intowasm-bindgen:mainfrom Nov 29, 2023
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Ah, could you add a note to the changelog as well? |
Fixes wasm-bindgen#3707 Previously, `(*js).borrow().#rust_name` was being given the span of `rust_name`, which seems like a fairly harmless thing to do at first glance. However, it turns out that the span of a token also affects its hygiene - turns out proc macros have hygiene too, not just declarative macros! This caused a problem because the declaration of `js` had a span of `Span::call_site()`, but it was being accessed with `rust_name`'s span, which might be a different context where `js` doesn't exist. Usually this is fine because `Span::call_site()` is in the same context as the struct definition: normal code. However, when you put `#[wasm_bindgen]` inside a `macro_rules!`, `Span::call_site()` is now in the context of that `macro_rules!`, while `rust_name`'s span is still in normal code which can't access variables from inside `macro_rules!`. To fix that I've just removed the span from `(*js).borrow().#rust_name`, making it `Span::call_site()`. I don't think this should have any effect on diagnostics anyway, since I don't see how that code could ever cause a compile error.
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daxpedda
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Nov 29, 2023
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Fixes #3707
Previously,
(*js).borrow().#rust_namewas being given the span ofrust_name, which seems like a fairly harmless thing to do at first glance. However, it turns out that the span of a token also affects its hygiene - turns out proc macros have hygiene too, not just declarative macros!This caused a problem because the declaration of
jshad a span ofSpan::call_site(), but it was being accessed withrust_name's span, which might be a different context wherejsdoesn't exist.Usually this is fine because
Span::call_site()is in the same context as the struct definition: normal code. However, when you put#[wasm_bindgen]inside amacro_rules!,Span::call_site()is now in the context of thatmacro_rules!, whilerust_name's span is still in normal code which can't access variables from insidemacro_rules!.To fix that I've just removed the span fromTurns out it was used, so I just got rid of the span on(*js).borrow().#rust_name, making itSpan::call_site(). I don't think this should have any effect on diagnostics anyway, since I don't see how that code could ever cause a compile error.jsinstead of the whole thing.