support OverloadResolutionPriority for extension methods

[BarionLP]

I recently had the issue of ambiguous calls with extension methods from different classes (#108960)
when trying to fix this with the OverloadResolutionPriorityAttribute it unexpectedly did not work because the attribute only seems to affect methods in the same class.
I think this attribute should affect overloading in general and not only in specific scenarios.

[huoyaoyuan]

This is the wrong repository for this topic. It's a compile time feature that belongs to csharplang repository.

This was explicitly rejected in the early design of the feature: https://github.com/dotnet/csharplang/blob/main/meetings%2F2024%2FLDM-2024-05-13.md

[BarionLP]

This is the wrong repository for this topic. It's a compile time feature that belongs to csharplang repository.

sorry

This was explicitly rejected in the early design of the feature:

after reading the reasons I do understand the decision but I do want to raise attention to my problem. maybe a different solution can be found?

[julealgon]

maybe a different solution can be found?

@BarionLP have you considered creating a new extension methods class with 2 methods, each redirecting to your specific extensions, and then annotating those with the overload attribute?

Sure, it is not even close to ideal, but might serve as a workaround for you.

[BarionLP]

maybe a different solution can be found?

@BarionLP have you considered creating a new extension methods class with 2 methods, each redirecting to your specific extensions, and then annotating those with the overload attribute?

Sure, it is not even close to ideal, but might serve as a workaround for you.

might work in other situations but in this case the signature is too similar (only differs by generic constrains)

[julealgon]

might work in other situations but in this case the signature is too similar (only differs by generic constrains)

You might still make it work if you "force" the signature to be different by introducing a "dummy" default parameter to one of them @BarionLP .

For example, there will cause problems since you can't have overloads differ only by generic constraints:

public static class MyExtensions
{
    public static void Do<T>(T thing) => ExtensionClass1.Do(thing);

    [OverloadResolutionPriority(1)]
    public static void Do<TSomething>(TSomething thing)
        where TSomething : ISomething
        => ExtensionsClass2.Do(thing);        
}

But this should work:

public static class MyExtensions
{
    public static void Do<T>(T thing) => ExtensionClass1.Do(thing);

    [OverloadResolutionPriority(1)]
    public static void Do<TSomething>(TSomething thing, object dummy = null)
        where TSomething : ISomething
        => ExtensionsClass2.Do(thing);
}

[BarionLP]

But this should work:

thank you @julealgon, but unfortunally I can't get it to work with this
this is the issue I'm trying to solve thomhurst/TUnit#922
file: https://github.com/thomhurst/TUnit/blob/main/TUnit.Assertions/Assertions/Generics/GenericIsExtensions_Namespaced.cs#L14