IDE0005 does not distinguish between overloaded extension methods

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Version Used:

$ dotnet --version
9.0.102

Steps to Reproduce:

Run dotnet build on a simple project with .csproj:

<Project Sdk="Microsoft.NET.Sdk">
    <PropertyGroup>
        <OutputType>Exe</OutputType>
        <TargetFramework>net9.0</TargetFramework>

        <EnforceCodeStyleInBuild>true</EnforceCodeStyleInBuild>
        <WarningsAsErrors>IDE0005</WarningsAsErrors>
        <GenerateDocumentationFile>true</GenerateDocumentationFile>
        <NoWarn>CS1591;CS8321</NoWarn>
    </PropertyGroup>
</Project>

and Program.cs:

using System.Data;
using System.Linq;

static void Test(EnumerableRowCollection<object> target)
{
     // These two lines call the same extension method, Linq is not used.
     // But uncommenting the first line makes IDE0005 go away incorrectly

     // _ = target.Where(_ => true);
     _ = EnumerableRowCollectionExtensions.Where(target, _ => true);
}

Diagnostic Id:

IDE0005: Using directive is unnecessary.

Expected Behavior:

IDE0005 is triggered when nothing from System.Linq is used.

Actual Behavior:

using System.Linq; does not cause IDE0005 build error.

This is because the Roslyn logic in WithUsingNamespacesAndTypesBinder.cs that determines which extension methods from usings are being used does not distinguish between overloads. It only looks at the method name and arity, not the (this) parameter type.

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This might be related to:

• IDE0005 is not reported if a code have same name extension methods. #54283
• Support System.Linq extensions in EE without manually importing it #44956
• IDE0005 doesn't find all unused directives #43742

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Observation: The Rider/Resharper RedundantUsingDirective inspection does not have this issue.

[AlekseyTs]

@jaredpar My recommendation is closing as "Won't fix"/"Not planned"