Replace shared PolyfillExtensions partial class with unique per-file extension classes

[Copilot]

Plan: Replace PolyfillExtensions with Unique Extension Classes

• Understand current structure and choose naming convention
• Update all .cs files to use unique class names based on file path
• Remove PolyfillExtensions.cs file (no longer needed)
• Update List-Signatures.ps1 to skip the new unique class names
• Build successfully with new changes
• Run tests to ensure functionality is maintained (246/252 passed, 6 failures are environmental)
• Address code review feedback
• Run security checks (0 issues found)
• Remove redundant using directives (21 files cleaned up)

Summary

Successfully refactored all member polyfill extension classes and cleaned up redundant using directives.

Latest Changes:

• Removed redundant using System.Diagnostics.CodeAnalysis; from 21 attribute definition files
• These files declare types within the System.Diagnostics.CodeAnalysis namespace, so they don't need to import it

Original prompt

Currently, we use one class called PolyfillExtensions for all member polyfills. This is proving to be cumbersome.

Let's instead name each extensions class uniquely. Perhaps MemberPolyfills_(random sequence). Feel free to suggest a more efficient naming convention.

Each class therefore needs to be excluded from coverage. And none of them needs to be partial.

The signatures PowerShell script may need to be updated too.

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[Copilot]

Pull request overview

This PR refactors the polyfill extension mechanism by replacing a single shared PolyfillExtensions partial class (with numbered variants) with unique, individually named extension classes following the pattern MemberPolyfills_{Version}_{Type}. This improves code organization and eliminates the need for multiple partial class definitions.

Changes:

• Replaced all PolyfillExtensions, PolyfillExtensions2, and PolyfillExtensions3 partial classes with 98 uniquely named MemberPolyfills_* classes
• Added [ExcludeFromCodeCoverage] attribute and using System.Diagnostics.CodeAnalysis; to all polyfill extension classes
• Updated PowerShell signature generation script to filter new class naming pattern
• Removed the now-obsolete PolyfillExtensions.cs file

Reviewed changes

Copilot reviewed 117 out of 117 changed files in this pull request and generated no comments.

File	Description
PolyShim/PolyfillExtensions.cs	Removed obsolete partial class definitions that are no longer needed
PolyShim/List-Signatures.ps1	Updated regex pattern to skip new MemberPolyfills_* classes in signature generation
PolyShim/Net*/*.cs (98 files)	Renamed extension classes from PolyfillExtensions* to MemberPolyfills_{Version}_{Type}, added [ExcludeFromCodeCoverage] attribute and required using directive, removed partial modifier
PolyShim/NetCore*/*.cs (attribute files)	Added using System.Diagnostics.CodeAnalysis; directive to attribute definition files for consistency

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[Tyrrrz]

@copilot remove redundant using directives

[Copilot]

@copilot remove redundant using directives

Removed redundant using System.Diagnostics.CodeAnalysis; from 21 attribute definition files that declare types within that namespace. Commit: 2c78284

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  • Triggering command: /usr/share/dotnet/dotnet /usr/share/dotnet/dotnet exec --runtimeconfig /home/REDACTED/work/PolyShim/PolyShim/PolyShim.Tests/bin/Release/net10.0/PolyShim.Tests.runtimeconfig.json --depsfile /home/REDACTED/work/PolyShim/PolyShim/PolyShim.Tests/bin/Release/net10.0/PolyShim.Tests.deps.json /home/REDACTED/work/PolyShim/PolyShim/PolyShim.Tests/bin/Release/net10.0/testhost.dll --port 34411 --endpoint 127.0.0.1:034411 --role client --parentprocessid 4235 --telemetryoptedin false (dns block)

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