Add polyfills for ArgumentNullException.ThrowIfNull(...), ArgumentException.ThrowIfNullOrEmpty(...) and ArgumentException.ThrowIfNullOrWhiteSpace(...) (#37)

Co-authored-by: Copilot <[email protected]>

Author: Tyrrrz

PolyShim.Tests/Net60/ArgumentNullExceptionTests.cs

@@ -0,0 +1,25 @@
+using System;
+using FluentAssertions;
+using Xunit;
+
+namespace PolyShim.Tests.Net60;
+
+public class ArgumentNullExceptionTests
+{
+    [Fact]
+    public void ThrowIfNull_Test()
+    {
+        // Arrange
+        const string notNullValue = "Hello, World!";
+        const string? nullValue = null;
+
+        // Act & assert
+        ArgumentNullException.ThrowIfNull(notNullValue);
+
+        var ex = Assert.Throws<ArgumentNullException>(() =>
+            ArgumentNullException.ThrowIfNull(nullValue)
+        );
+
+        ex.ParamName.Should().Be(nameof(nullValue));
+    }
+}

PolyShim.Tests/Net70/ArgumentExceptionTests.cs

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+using System;
+using FluentAssertions;
+using Xunit;
+
+namespace PolyShim.Tests.Net70;
+
+public class ArgumentExceptionTests
+{
+    [Fact]
+    public void ThrowIfNullOrEmpty_Test()
+    {
+        // Arrange
+        const string notEmptyValue = "Hello, World!";
+        const string emptyValue = "";
+        const string? nullValue = null;
+
+        // Act & assert
+        ArgumentException.ThrowIfNullOrEmpty(notEmptyValue);
+
+        var ex1 = Assert.Throws<ArgumentException>(() =>
+            ArgumentException.ThrowIfNullOrEmpty(emptyValue)
+        );
+
+        ex1.ParamName.Should().Be(nameof(emptyValue));
+
+        var ex2 = Assert.Throws<ArgumentNullException>(() =>
+            ArgumentException.ThrowIfNullOrEmpty(nullValue)
+        );
+
+        ex2.ParamName.Should().Be(nameof(nullValue));
+    }
+
+    [Fact]
+    public void ThrowIfNullOrWhiteSpace_Test()
+    {
+        // Arrange
+        const string notWhiteSpaceValue = "Hello, World!";
+        const string whiteSpaceValue = "   ";
+        const string? nullValue = null;
+
+        // Act & assert
+        ArgumentException.ThrowIfNullOrWhiteSpace(notWhiteSpaceValue);
+
+        var ex1 = Assert.Throws<ArgumentException>(() =>
+            ArgumentException.ThrowIfNullOrWhiteSpace(whiteSpaceValue)
+        );
+
+        ex1.ParamName.Should().Be(nameof(whiteSpaceValue));
+
+        var ex2 = Assert.Throws<ArgumentNullException>(() =>
+            ArgumentException.ThrowIfNullOrWhiteSpace(nullValue)
+        );
+
+        ex2.ParamName.Should().Be(nameof(nullValue));
+    }
+}

PolyShim/Net60/ArgumentNullException.cs

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+// The following comment is required to instruct analyzers to skip this file
+// <auto-generated/>
+
+#if (NETCOREAPP && !NET6_0_OR_GREATER) || (NETFRAMEWORK) || (NETSTANDARD)
+#nullable enable
+// ReSharper disable RedundantUsingDirective
+// ReSharper disable CheckNamespace
+// ReSharper disable InconsistentNaming
+// ReSharper disable PartialTypeWithSinglePart
+
+using System;
+using System.Runtime.CompilerServices;
+
+internal static partial class PolyfillExtensions
+{
+    extension(ArgumentNullException)
+    {
+        // https://learn.microsoft.com/dotnet/api/system.argumentnullexception.throwifnull#system-argumentnullexception-throwifnull(system-object-system-string)
+        public static void ThrowIfNull(object? argument, [CallerArgumentExpression(nameof(argument))] string? paramName = null)
+        {
+            if (argument is null)
+                throw new ArgumentNullException(paramName);
+        }
+    }
+}
+#endif

PolyShim/Net70/ArgumentException.cs

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+// The following comment is required to instruct analyzers to skip this file
+// <auto-generated/>
+
+#if (NETCOREAPP && !NET7_0_OR_GREATER) || (NETFRAMEWORK) || (NETSTANDARD)
+#nullable enable
+// ReSharper disable RedundantUsingDirective
+// ReSharper disable CheckNamespace
+// ReSharper disable InconsistentNaming
+// ReSharper disable PartialTypeWithSinglePart
+
+using System;
+using System.Runtime.CompilerServices;
+
+internal static partial class PolyfillExtensions
+{
+    extension(ArgumentException)
+    {
+        // https://learn.microsoft.com/dotnet/api/system.argumentexception.throwifnullorempty
+        public static void ThrowIfNullOrEmpty(string? argument, [CallerArgumentExpression(nameof(argument))] string? paramName = null)
+        {
+            if (argument is null)
+                throw new ArgumentNullException(paramName);
+
+            if (string.IsNullOrEmpty(argument))
+                throw new ArgumentException("The value cannot be an empty string.", paramName);
+        }
+
+        // https://learn.microsoft.com/dotnet/api/system.argumentexception.throwifnullorwhitespace
+        public static void ThrowIfNullOrWhiteSpace(string? argument, [CallerArgumentExpression(nameof(argument))] string? paramName = null)
+        {
+            if (argument is null)
+                throw new ArgumentNullException(paramName);
+
+            if (string.IsNullOrWhiteSpace(argument))
+                throw new ArgumentException("The value cannot be an empty string or composed entirely of whitespace.", paramName);
+        }
+    }
+}
+#endif