Add ArgHelper utility to perform argument validation

Add `ArgHelper`, which contains methods that mimic the .NET 8+ APIs: `ArgumentNullException.Throw*`, `ArgumentException.Throw*`, and `ArgumentOutOfRangeException.Throw*`. On .NET 8+, the `ArgHelper` APIs delegate to the .NET APIs. However, on other TFMs, they provide a similar implementation.

Author: DustinCampbell

src/Shared/Microsoft.AspNetCore.Razor.Utilities.Shared.Test/ArgHelperTests.cs

@@ -0,0 +1,155 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the MIT license. See License.txt in the project root for license information.
+
+using System;
+using Xunit;
+
+namespace Microsoft.AspNetCore.Razor.Utilities.Shared.Test;
+
+public class ArgHelperTests
+{
+    [Theory]
+    [InlineData(null, typeof(ArgumentNullException))]
+    [InlineData("test")]
+    public void ThrowIfNull(string? s, Type? exceptionType = null)
+    {
+        Verify(() => ArgHelper.ThrowIfNull(s), exceptionType);
+    }
+
+    [Fact]
+    public unsafe void ThrowIfNull_NullPtr_Throws()
+    {
+        byte* ptr = null;
+
+        Assert.Throws<ArgumentNullException>(() =>
+        {
+            ArgHelper.ThrowIfNull(ptr);
+        });
+    }
+
+    [Fact]
+    public unsafe void ThrowIfNull_Ptr_DoesNotThrow()
+    {
+        fixed (byte* ptr = new byte[8])
+        {
+            ArgHelper.ThrowIfNull(ptr);
+        }
+    }
+
+    [Theory]
+    [InlineData(null, typeof(ArgumentNullException))]
+    [InlineData("", typeof(ArgumentException))]
+    [InlineData("    ")]
+    [InlineData("test")]
+    public void ThrowIfNullOrEmpty(string? s, Type? exceptionType = null)
+    {
+        Verify(() => ArgHelper.ThrowIfNullOrEmpty(s), exceptionType);
+    }
+
+    [Theory]
+    [InlineData(null, typeof(ArgumentNullException))]
+    [InlineData("", typeof(ArgumentException))]
+    [InlineData("    ", typeof(ArgumentException))]
+    [InlineData("test")]
+    public void ThrowIfNullOrWhiteSpace(string? s, Type? exceptionType = null)
+    {
+        Verify(() => ArgHelper.ThrowIfNullOrWhiteSpace(s), exceptionType);
+    }
+
+    [Theory]
+    [InlineData(null, null, typeof(ArgumentOutOfRangeException))]
+    [InlineData(null, "test")]
+    [InlineData("test", null)]
+    [InlineData("test", "test", typeof(ArgumentOutOfRangeException))]
+    [InlineData("test", "TeSt")]
+    public void ThrowIfEqual(string? s1, string? s2, Type? exceptionType = null)
+    {
+        Verify(() => ArgHelper.ThrowIfEqual(s1, s2), exceptionType);
+    }
+
+    [Theory]
+    [InlineData(null, null)]
+    [InlineData(null, "test", typeof(ArgumentOutOfRangeException))]
+    [InlineData("test", null, typeof(ArgumentOutOfRangeException))]
+    [InlineData("test", "test")]
+    [InlineData("test", "TeSt", typeof(ArgumentOutOfRangeException))]
+    public void ThrowIfNotEqual(string? s1, string? s2, Type? exceptionType = null)
+    {
+        Verify(() => ArgHelper.ThrowIfNotEqual(s1, s2), exceptionType);
+    }
+
+    [Theory]
+    [InlineData(0, typeof(ArgumentOutOfRangeException))]
+    [InlineData(-1)]
+    [InlineData(1)]
+    public void ThrowIfZero(int v, Type? exceptionType = null)
+    {
+        Verify(() => ArgHelper.ThrowIfZero(v), exceptionType);
+    }
+
+    [Theory]
+    [InlineData(0)]
+    [InlineData(-1, typeof(ArgumentOutOfRangeException))]
+    [InlineData(1)]
+    public void ThrowIfNegative(int v, Type? exceptionType = null)
+    {
+        Verify(() => ArgHelper.ThrowIfNegative(v), exceptionType);
+    }
+
+    [Theory]
+    [InlineData(0, typeof(ArgumentOutOfRangeException))]
+    [InlineData(-1, typeof(ArgumentOutOfRangeException))]
+    [InlineData(1)]
+    public void ThrowIfNegativeOrZero(int v, Type? exceptionType = null)
+    {
+        Verify(() => ArgHelper.ThrowIfNegativeOrZero(v), exceptionType);
+    }
+
+    [Theory]
+    [InlineData(42, 42)]
+    [InlineData(41, 42)]
+    [InlineData(43, 42, typeof(ArgumentOutOfRangeException))]
+    public void ThrowIfGreaterThan(int v1, int v2, Type? exceptionType = null)
+    {
+        Verify(() => ArgHelper.ThrowIfGreaterThan(v1, v2), exceptionType);
+    }
+
+    [Theory]
+    [InlineData(42, 42, typeof(ArgumentOutOfRangeException))]
+    [InlineData(41, 42)]
+    [InlineData(43, 42, typeof(ArgumentOutOfRangeException))]
+    public void ThrowIfGreaterThanOrEqual(int v1, int v2, Type? exceptionType = null)
+    {
+        Verify(() => ArgHelper.ThrowIfGreaterThanOrEqual(v1, v2), exceptionType);
+    }
+
+    [Theory]
+    [InlineData(42, 42)]
+    [InlineData(41, 42, typeof(ArgumentOutOfRangeException))]
+    [InlineData(43, 42)]
+    public void ThrowIfLessThan(int v1, int v2, Type? exceptionType = null)
+    {
+        Verify(() => ArgHelper.ThrowIfLessThan(v1, v2), exceptionType);
+    }
+
+    [Theory]
+    [InlineData(42, 42, typeof(ArgumentOutOfRangeException))]
+    [InlineData(41, 42, typeof(ArgumentOutOfRangeException))]
+    [InlineData(43, 42)]
+    public void ThrowIfLessThanOrEqual(int v1, int v2, Type? exceptionType = null)
+    {
+        Verify(() => ArgHelper.ThrowIfLessThanOrEqual(v1, v2), exceptionType);
+    }
+
+    private static void Verify(Action a, Type? exceptionType = null)
+    {
+        if (exceptionType is not null)
+        {
+            Assert.Throws(exceptionType, a);
+        }
+        else
+        {
+            a();
+        }
+    }
+}

src/Shared/Microsoft.AspNetCore.Razor.Utilities.Shared.Test/Microsoft.AspNetCore.Razor.Utilities.Shared.Test.csproj

@@ -3,6 +3,7 @@
   <PropertyGroup>
     <TargetFrameworks>$(DefaultNetCoreTargetFrameworks)</TargetFrameworks>
     <TargetFrameworks Condition="'$(OS)' == 'Windows_NT'">$(TargetFrameworks);$(DefaultNetFxTargetFramework)</TargetFrameworks>
+    <AllowUnsafeBlocks>True</AllowUnsafeBlocks>
   </PropertyGroup>
 
   <ItemGroup>