nullable fix

Pilz/NullableAttributes.cs

@@ -0,0 +1,204 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+#if NETSTANDARD2_0
+
+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
+{ }
+
+/// <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
+{ }
+
+/// <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
+{ }
+
+/// <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
+{ }
+
+/// <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
+{
+    /// <summary>Initializes the attribute with the specified return value condition.</summary>
+    /// <param name="returnValue">
+    /// The return value condition. If the method returns this value, the associated parameter may be null.
+    /// </param>
+    public MaybeNullWhenAttribute(bool returnValue) => ReturnValue = returnValue;
+
+    /// <summary>Gets the return value condition.</summary>
+    public bool ReturnValue { get; }
+}
+
+/// <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
+{
+    /// <summary>Initializes the attribute with the specified return value condition.</summary>
+    /// <param name="returnValue">
+    /// The return value condition. If the method returns this value, the associated parameter will not be null.
+    /// </param>
+    public NotNullWhenAttribute(bool returnValue) => ReturnValue = returnValue;
+
+    /// <summary>Gets the return value condition.</summary>
+    public bool ReturnValue { get; }
+}
+
+/// <summary>Specifies that the output will be non-null if the named parameter is non-null.</summary>
+[AttributeUsage(AttributeTargets.Parameter | AttributeTargets.Property | AttributeTargets.ReturnValue, AllowMultiple = true, Inherited = false)]
+#if SYSTEM_PRIVATE_CORELIB
+public
+#else
+internal
+#endif
+    sealed class NotNullIfNotNullAttribute : Attribute
+{
+    /// <summary>Initializes the attribute with the associated parameter name.</summary>
+    /// <param name="parameterName">
+    /// The associated parameter name.  The output will be non-null if the argument to the parameter specified is non-null.
+    /// </param>
+    public NotNullIfNotNullAttribute(string parameterName) => ParameterName = parameterName;
+
+    /// <summary>Gets the associated parameter name.</summary>
+    public string ParameterName { get; }
+}
+
+/// <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
+{ }
+
+/// <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
+{
+    /// <summary>Initializes the attribute with the specified parameter value.</summary>
+    /// <param name="parameterValue">
+    /// The condition parameter value. Code after the method will be considered unreachable by diagnostics if the argument to
+    /// the associated parameter matches this value.
+    /// </param>
+    public DoesNotReturnIfAttribute(bool parameterValue) => ParameterValue = parameterValue;
+
+    /// <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
+{
+    /// <summary>Initializes the attribute with a field or property member.</summary>
+    /// <param name="member">
+    /// The field or property member that is promised to be not-null.
+    /// </param>
+    public MemberNotNullAttribute(string member) => Members = [member];
+
+    /// <summary>Initializes the attribute with the list of field and property members.</summary>
+    /// <param name="members">
+    /// The list of field and property members that are promised to be not-null.
+    /// </param>
+    public MemberNotNullAttribute(params string[] members) => Members = members;
+
+    /// <summary>Gets field or property member names.</summary>
+    public string[] Members { get; }
+}
+
+/// <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
+{
+    /// <summary>Initializes the attribute with the specified return value condition and a field or property member.</summary>
+    /// <param name="returnValue">
+    /// The return value condition. If the method returns this value, the associated field or property member will not be null.
+    /// </param>
+    /// <param name="member">
+    /// The field or property member that is promised to be not-null.
+    /// </param>
+    public MemberNotNullWhenAttribute(bool returnValue, string member)
+    {
+        ReturnValue = returnValue;
+        Members = [member];
+    }
+
+    /// <summary>Initializes the attribute with the specified return value condition and list of field and property members.</summary>
+    /// <param name="returnValue">
+    /// The return value condition. If the method returns this value, the associated field and property members will not be null.
+    /// </param>
+    /// <param name="members">
+    /// The list of field and property members that are promised to be not-null.
+    /// </param>
+    public MemberNotNullWhenAttribute(bool returnValue, params string[] members)
+    {
+        ReturnValue = returnValue;
+        Members = members;
+    }
+
+    /// <summary>Gets the return value condition.</summary>
+    public bool ReturnValue { get; }
+
+    /// <summary>Gets field or property member names.</summary>
+    public string[] Members { get; }
+}
+
+#endif

Pilz/Pilz.csproj

@@ -1,11 +1,15 @@
 <Project Sdk="Microsoft.NET.Sdk">
   
   <PropertyGroup>
-    <TargetFrameworks>net8.0</TargetFrameworks>
+    <TargetFrameworks>net8.0;netstandard2.0</TargetFrameworks>
     <LangVersion>latest</LangVersion>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>annotations</Nullable>
-    <Version>2.4.6</Version>
+    <Version>2.4.7</Version>
+  </PropertyGroup>
+
+  <PropertyGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">
+    <NoWarn>$(NoWarn);nullable</NoWarn>
   </PropertyGroup>
   
   <ItemGroup>