Remove unnecessary conditional compilation

Author: Patonymous

src/Tools/LeanCode.CodeAnalysis/NetStandard21Compatibility/System.Diagnostics.CodeAnalysis.NullableAttributes.cs

@@ -6,57 +6,31 @@
 
 namespace System.Diagnostics.CodeAnalysis;
 
-#if !NETSTANDARD2_1
 /// <summary>Specifies that null is allowed as an input even if the corresponding type disallows it.</summary>
 [AttributeUsage(AttributeTargets.Field | AttributeTargets.Parameter | AttributeTargets.Property, Inherited = false)]
-#if SYSTEM_PRIVATE_CORELIB
-public
-#else
-internal
-#endif
-sealed class AllowNullAttribute : Attribute { }
+internal sealed class AllowNullAttribute : Attribute { }
 
 /// <summary>Specifies that null is disallowed as an input even if the corresponding type allows it.</summary>
 [AttributeUsage(AttributeTargets.Field | AttributeTargets.Parameter | AttributeTargets.Property, Inherited = false)]
-#if SYSTEM_PRIVATE_CORELIB
-public
-#else
-internal
-#endif
-sealed class DisallowNullAttribute : Attribute { }
+internal sealed class DisallowNullAttribute : Attribute { }
 
 /// <summary>Specifies that an output may be null even if the corresponding type disallows it.</summary>
 [AttributeUsage(
     AttributeTargets.Field | AttributeTargets.Parameter | AttributeTargets.Property | AttributeTargets.ReturnValue,
     Inherited = false
 )]
-#if SYSTEM_PRIVATE_CORELIB
-public
-#else
-internal
-#endif
-sealed class MaybeNullAttribute : Attribute { }
+internal sealed class MaybeNullAttribute : Attribute { }
 
 /// <summary>Specifies that an output will not be null even if the corresponding type allows it. Specifies that an input argument was not null when the call returns.</summary>
 [AttributeUsage(
     AttributeTargets.Field | AttributeTargets.Parameter | AttributeTargets.Property | AttributeTargets.ReturnValue,
     Inherited = false
 )]
-#if SYSTEM_PRIVATE_CORELIB
-public
-#else
-internal
-#endif
-sealed class NotNullAttribute : Attribute { }
+internal sealed class NotNullAttribute : Attribute { }
 
 /// <summary>Specifies that when a method returns <see cref="ReturnValue"/>, the parameter may be null even if the corresponding type disallows it.</summary>
 [AttributeUsage(AttributeTargets.Parameter, Inherited = false)]
-#if SYSTEM_PRIVATE_CORELIB
-public
-#else
-internal
-#endif
-sealed class MaybeNullWhenAttribute : Attribute
+internal sealed class MaybeNullWhenAttribute : Attribute
 {
     /// <summary>Initializes the attribute with the specified return value condition.</summary>
     /// <param name="returnValue">
@@ -70,12 +44,7 @@ sealed class MaybeNullWhenAttribute : Attribute
 
 /// <summary>Specifies that when a method returns <see cref="ReturnValue"/>, the parameter will not be null even if the corresponding type allows it.</summary>
 [AttributeUsage(AttributeTargets.Parameter, Inherited = false)]
-#if SYSTEM_PRIVATE_CORELIB
-public
-#else
-internal
-#endif
-sealed class NotNullWhenAttribute : Attribute
+internal sealed class NotNullWhenAttribute : Attribute
 {
     /// <summary>Initializes the attribute with the specified return value condition.</summary>
     /// <param name="returnValue">
@@ -93,12 +62,7 @@ sealed class NotNullWhenAttribute : Attribute
     AllowMultiple = true,
     Inherited = false
 )]
-#if SYSTEM_PRIVATE_CORELIB
-public
-#else
-internal
-#endif
-sealed class NotNullIfNotNullAttribute : Attribute
+internal sealed class NotNullIfNotNullAttribute : Attribute
 {
     /// <summary>Initializes the attribute with the associated parameter name.</summary>
     /// <param name="parameterName">
@@ -112,21 +76,11 @@ sealed class NotNullIfNotNullAttribute : Attribute
 
 /// <summary>Applied to a method that will never return under any circumstance.</summary>
 [AttributeUsage(AttributeTargets.Method, Inherited = false)]
-#if SYSTEM_PRIVATE_CORELIB
-public
-#else
-internal
-#endif
-sealed class DoesNotReturnAttribute : Attribute { }
+internal sealed class DoesNotReturnAttribute : Attribute { }
 
 /// <summary>Specifies that the method will not return if the associated Boolean parameter is passed the specified value.</summary>
 [AttributeUsage(AttributeTargets.Parameter, Inherited = false)]
-#if SYSTEM_PRIVATE_CORELIB
-public
-#else
-internal
-#endif
-sealed class DoesNotReturnIfAttribute : Attribute
+internal sealed class DoesNotReturnIfAttribute : Attribute
 {
     /// <summary>Initializes the attribute with the specified parameter value.</summary>
     /// <param name="parameterValue">
@@ -138,16 +92,10 @@ sealed class DoesNotReturnIfAttribute : Attribute
     /// <summary>Gets the condition parameter value.</summary>
     public bool ParameterValue { get; }
 }
-#endif
 
 /// <summary>Specifies that the method or property will ensure that the listed field and property members have not-null values.</summary>
 [AttributeUsage(AttributeTargets.Method | AttributeTargets.Property, Inherited = false, AllowMultiple = true)]
-#if SYSTEM_PRIVATE_CORELIB
-public
-#else
-internal
-#endif
-sealed class MemberNotNullAttribute : Attribute
+internal sealed class MemberNotNullAttribute : Attribute
 {
     /// <summary>Initializes the attribute with a field or property member.</summary>
     /// <param name="member">
@@ -167,12 +115,7 @@ sealed class MemberNotNullAttribute : Attribute
 
 /// <summary>Specifies that the method or property will ensure that the listed field and property members have not-null values when returning with the specified return value condition.</summary>
 [AttributeUsage(AttributeTargets.Method | AttributeTargets.Property, Inherited = false, AllowMultiple = true)]
-#if SYSTEM_PRIVATE_CORELIB
-public
-#else
-internal
-#endif
-sealed class MemberNotNullWhenAttribute : Attribute
+internal sealed class MemberNotNullWhenAttribute : Attribute
 {
     /// <summary>Initializes the attribute with the specified return value condition and a field or property member.</summary>
     /// <param name="returnValue">