Self-assignment instead of delegate creation

[PetSerAl]

runtime/src/libraries/System.Security.Claims/src/System/Security/Claims/ClaimsPrincipal.cs

Line 31 in 1303e42

private static Func<ClaimsPrincipal> s_principalSelector = ClaimsPrincipalSelector;

Here it is basically self-assignment: ClaimsPrincipalSelector property read the same field it is assigned to. As result ClaimsPrincipalSelector property ends up being null: https://sharplab.io/#v2:C4LgTgrgdgNAJiA1AHwAIEYB0GCcAKDTAZQFMBjCMAS2AE9MBhAGwEMqBbAZ0dY84AVqUMlQAOLJjzZdBVYWImkm5YAHswAAiqcNUCEyYBKANxA=
Looks like it should be SelectClaimsPrincipal (to create delegate from method) instead of ClaimsPrincipalSelector.

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[KalleOlaviNiemitalo]

It looks like a bug indeed. But .NET Framework behaves the same, and ClaimsPrincipal.Current tolerates s_principalSelector being null, so I don't think it's causing any actual problem. https://learn.microsoft.com/dotnet/api/system.security.claims.claimsprincipal.claimsprincipalselector?view=net-9.0 even documents that the default value is null.

I think the initialisation of ClaimsPrincipal.s_principalSelector should be just removed, and the type of ClaimsPrincipal.s_principalSelector and ClaimsPrincipal.ClaimsPrincipalSelector should be changed to nullable Func<ClaimsPrincipal>?.