Enable nullability in DesignerActionMethodItem

[gpetrou]

Proposed changes

• Enable nullability in DesignerActionMethodItem.

Microsoft Reviewers: Open in CodeFlow

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 76.04200%. Comparing base (92919a1) to head (cc9a3d1).

Additional details and impacted files

@@                 Coverage Diff                 @@
##                main      #12676         +/-   ##
===================================================
- Coverage   76.05370%   76.04200%   -0.01171%     
===================================================
  Files           3269        3269                 
  Lines         643544      643572         +28     
  Branches       47429       47430          +1     
===================================================
- Hits          489439      489385         -54     
- Misses        150545      150622         +77     
- Partials        3560        3565          +5     

Flag	Coverage Δ
Debug	76.04200% <100.00000%> (-0.01171%)	⬇️
integration	18.03442% <0.00000%> (-0.01502%)	⬇️
production	50.01692% <100.00000%> (-0.02357%)	⬇️
test	96.93778% <ø> (+0.00052%)	⬆️
unit	47.47548% <100.00000%> (+0.01057%)	⬆️

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[ricardobossan]

Please add a comment explaining in detail why MemberName! can never be null.

[gpetrou]

This can actually be null, but I did not want to add an extra exception to it.
@lonitra should I throw an exception instead?

[Tanya-Solyanik]

It's appropriate to add a more descriptive exception in this case. InvalidOperationException with message "Could not find method '{0}'."

Copilot reviewed 2 out of 3 changed files in this pull request and generated no comments.

Files not reviewed (1)

• src/System.Windows.Forms.Design/src/PublicAPI.Shipped.txt: Language not supported

[Tanya-Solyanik]

System.ComponentModel.Design.Tests.DesignerActionMethodItemTests.Invoke_NullMemberName_ThrowsArgumentNullException

Assert.Throws() Failure: Exception type was not an exact match\r\nExpected: typeof(System.ArgumentNullException)\r\nActual: typeof(System.InvalidOperationException)\r\n---- System.InvalidOperationException : Operation is not valid due to the current state of the object.

Stack trace
at System.ComponentModel.Design.Tests.DesignerActionMethodItemTests.Invoke_NullMemberName_ThrowsArgumentNullException() in D:\a_work\1\s\src\System.Windows.Forms.Design\tests\UnitTests\System\ComponentModel\Design\DesignerActionMethodItemTests.cs:line 227
at System.Reflection.MethodBaseInvoker.InterpretedInvoke_Method(Object obj, IntPtr* args)
at System.Reflection.MethodBaseInvoker.InvokeWithNoArgs(Object obj, BindingFlags invokeAttr)
----- Inner Stack Trace -----
at System.ComponentModel.Design.DesignerActionMethodItem.Invoke() in D:\a_work\1\s\src\System.Windows.Forms.Design\src\System\ComponentModel\Design\DesignerActionMethodItem.cs:line 113