[API Proposal]: Enhance RequiresDynamicCode Attribute to apply to class

[LakshanF]

Background and motivation

There are scenarios where it makes sense to apply this attribute to a class as discussed in this PR. In the particular case, the internal class is around runtime code generation and applying at the class level results in a better user experience as opposed to annotating at member level.

The trimmer equivalent attribute, RequiresUnreferencedCode, already allows the attribute to be applied at class level.

API Proposal

 namespace System.Diagnostics.CodeAnalysis
 {
     [AttributeUsage(
         AttributeTargets.Method |
         AttributeTargets.Constructor |
+        AttributeTargets.Class,
         Inherited = false)]
     public partial class RequiresDynamicCodeAttribute: Attribute
     {
     }
 }

API Usage

[RequiresDynamicCode("The native code for Regex compilation might not be available at runtime.")]
internal abstract class RegexCompiler

Alternative Designs

None and leave the RequiresDynamicCodeAttribute class as is, which would require working around the issue

Risks

Requires Analyzers build for this attribute and NativeAot compiler to adjust to the enhanced scope.

[dotnet-issue-labeler]

I couldn't figure out the best area label to add to this issue. If you have write-permissions please help me learn by adding exactly one area label.

[tlakollo]

I added the api-ready-for-review I don't think we will discuss anything interesting in this PR. I think is only worth discussing this in the API review meeting.

[ghost]

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Issue Details

---

Background and motivation

There are scenarios where it makes sense to apply this attribute to a class as discussed in this PR. In the particular case, the internal class is around runtime code generation and applying at the class level results in a better user experience as opposed to annotating at member level.

The trimmer equivalent attribute, RequiresUnreferencedCode, already allows the attribute to be applied at class level.

API Proposal

 namespace System.Diagnostics.CodeAnalysis
 {
     [AttributeUsage(
         AttributeTargets.Method |
         AttributeTargets.Constructor |
+        AttributeTargets.Class,
         Inherited = false)]
     public partial class RequiresDynamicCodeAttribute: Attribute
     {
     }
 }

API Usage

[RequiresDynamicCode("The native code for Regex compilation might not be available at runtime.")]
internal abstract class RegexCompiler

Alternative Designs

None and leave the RequiresDynamicCodeAttribute class as is, which would require working around the issue

Risks

Requires Analyzers build for this attribute and NativeAot compiler to adjust to the enhanced scope.

Author:	LakshanF
Assignees:	-
Labels:	api-suggestion, area-System.Diagnostics, api-ready-for-review
Milestone:	-

[bartonjs]

Video

Looks good as proposed

 namespace System.Diagnostics.CodeAnalysis
 {
     [AttributeUsage(
         AttributeTargets.Method |
         AttributeTargets.Constructor |
+        AttributeTargets.Class,
         Inherited = false)]
     public partial class RequiresDynamicCodeAttribute: Attribute
     {
     }
 }