fix: Do not delay E0107 when there exists an assoc ty with the same name #151166
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HIR ty lowering was modified cc @fmease |
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r? @davidtwco rustbot has assigned @davidtwco. Use |
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r? tiif |
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This looks correct to me, thanks! @bors r+ rollup |
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fix: Do not delay E0107 when there exists an assoc ty with the same name Fixes rust-lang#148121 When we have the following code: ```rust trait Foo<T> {} impl Foo<T: Default> for String {} ``` we delay `E0107: wrong number of generic args` to suggest moving `T: Default` bound to the impl block's param declaration. The delay is determined by whether all the missing generic parameters are mentioned by those *wrong* assoc item constraints. But this delay is wrong when there exist any *correct* assoc item constraints, i.e. when we have an assoc type whose identifier is same with a missing generic parameter like in the following code: ```rust pub trait Super<X> { type X; } pub trait A {} impl A for dyn Super<X = ()> {} ```
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Rollup of 4 pull requests Successful merges: - #151155 (THIR patterns: Always use type `str` for string-constant-value nodes) - #151166 (fix: Do not delay E0107 when there exists an assoc ty with the same name) - #151172 (Use default field values in a few more cases) - #151185 (Disable `dump-ice-to-disk` on `i686-pc-windows-msvc`) r? @ghost
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Rollup merge of #151166 - issue-148121, r=tiif fix: Do not delay E0107 when there exists an assoc ty with the same name Fixes #148121 When we have the following code: ```rust trait Foo<T> {} impl Foo<T: Default> for String {} ``` we delay `E0107: wrong number of generic args` to suggest moving `T: Default` bound to the impl block's param declaration. The delay is determined by whether all the missing generic parameters are mentioned by those *wrong* assoc item constraints. But this delay is wrong when there exist any *correct* assoc item constraints, i.e. when we have an assoc type whose identifier is same with a missing generic parameter like in the following code: ```rust pub trait Super<X> { type X; } pub trait A {} impl A for dyn Super<X = ()> {} ```
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Fixes #148121
When we have the following code:
we delay
E0107: wrong number of generic argsto suggest movingT: Defaultbound to the impl block's param declaration.The delay is determined by whether all the missing generic parameters are mentioned by those wrong assoc item constraints.
But this delay is wrong when there exist any correct assoc item constraints, i.e. when we have an assoc type whose identifier is same with a missing generic parameter like in the following code: