chore(deps): update dependency polyfill to 9.3.1

[thomhurst]

This PR contains the following updates:

Package	Type	Update	Change
Polyfill	nuget	patch	9.3.0 -> 9.3.1

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Release Notes

SimonCropp/Polyfill (Polyfill)

v9.3.1

Compare Source

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Configuration

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This PR has been generated by Renovate Bot.

[claude]

Claude finished @thomhurst's task —— View job

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PR Review: Polyfill Dependency Update

Code Quality & Best Practices ✅

• Change scope: Simple, focused patch version update in Directory.Packages.props:62
• Centralized dependency management: Uses Central Package Management correctly
• Automated update: Well-managed by Renovate Bot with clear metadata

Potential Bugs or Issues 🚨

• Version mismatch detected: TUnit.Core.targets:11 still references 9.3.0 while Directory.Packages.props now specifies 9.3.1
  • This creates inconsistency between the centrally managed version and the embedded version used for non-CPM projects
  • Could lead to different Polyfill versions being used depending on project configuration
  • Recommendation: Update _TUnitPolyfillVersion in TUnit.Core.targets to match

Performance Considerations ✅

• Patch version updates typically include only bug fixes and performance improvements
• Polyfill provides compile-time type generation, so minimal runtime impact
• Used strategically only for older target frameworks (netstandard2.0/2.1, .NET Framework)

Security Concerns ✅

• Polyfill is a well-maintained library by Simon Cropp
• Patch version bump (9.3.0 → 9.3.1) is low-risk
• Library provides compile-time polyfills, not runtime dependencies
• No security vulnerabilities identified in this version range

Test Coverage Assessment 📋

• Current usage: Polyfill is used via using Polyfills; in:
  • TUnit.Engine/Utilities/ScopedAttributeFilter.cs:2
  • TUnit.Engine/Discovery/ReflectionHookDiscoveryService.cs:5
• Testing recommendation: Existing test suite should cover Polyfill usage indirectly
• Regression testing: Run full test suite, especially for .NET Standard 2.0/2.1 targets

Recommended Actions

1. Fix version mismatch: Update TUnit.Core.targets:11 to use version 9.3.1
2. Verify consistency: Ensure both CPM and non-CPM projects use the same Polyfill version
3. Test thoroughly: Run tests against multiple target frameworks, particularly legacy ones

Overall Assessment

✅ Approve with minor fix required

This is a safe patch update, but the version mismatch needs to be resolved to maintain consistency across the project.