.NET-Community-Toolkit/tests/CommunityToolkit.HighPerformance.UnitTests/Helpers/Test_ParallelHelper.ThrowExceptions.cs

// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.

using System.Linq;
using CommunityToolkit.HighPerformance.Helpers;
using Microsoft.VisualStudio.TestTools.UnitTesting;
using ArgumentOutOfRangeException = System.ArgumentOutOfRangeException;

namespace CommunityToolkit.HighPerformance.UnitTests.Helpers;

public partial class Test_ParallelHelper
{
    [TestMethod]
    public void Test_ParallelHelper_ParameterName_ThrowArgumentOutOfRangeExceptionForInvalidMinimumActionsPerThread()
    {
        try
        {
            ParallelHelper.For<DummyAction>(0, 1, -1);
        }
        catch (ArgumentOutOfRangeException e) when (e.GetType() == typeof(ArgumentOutOfRangeException))
        {
            string? name = (
                from method in typeof(ParallelHelper).GetMethods()
                where
                    method.Name == nameof(ParallelHelper.For) &&
                    method.IsGenericMethodDefinition
                let typeParams = method.GetGenericArguments()
                let normalParams = method.GetParameters()
                where
                    typeParams.Length == 1 &&
                    normalParams.Length == 3 &&
                    normalParams.All(p => p.ParameterType == typeof(int))
                select normalParams[2].Name).Single();

            Assert.AreEqual(e.ParamName, name);

            return;
        }

        Assert.Fail("Failed to raise correct exception");
    }

    [TestMethod]
    public void Test_ParallelHelper_ParameterName_ThrowArgumentOutOfRangeExceptionForStartGreaterThanEnd()
    {
        try
        {
            ParallelHelper.For<DummyAction>(1, 0);
        }
        catch (ArgumentOutOfRangeException e) when (e.GetType() == typeof(ArgumentOutOfRangeException))
        {
            string? name = (
                from method in typeof(ParallelHelper).GetMethods()
                where
                    method.Name == nameof(ParallelHelper.For) &&
                    method.IsGenericMethodDefinition
                let typeParams = method.GetGenericArguments()
                let normalParams = method.GetParameters()
                where
                    typeParams.Length == 1 &&
                    normalParams.Length == 2 &&
                    normalParams.All(p => p.ParameterType == typeof(int))
                select normalParams[0].Name).Single();

            Assert.AreEqual(e.ParamName, name);

            return;
        }

        Assert.Fail("Failed to raise correct exception");
    }

    [TestMethod]
    public void Test_ParallelHelper_ParameterName_ThrowArgumentOutOfRangeExceptionForTopGreaterThanBottom()
    {
        try
        {
            ParallelHelper.For2D<DummyAction2D>(1, 0, 0, 1);
        }
        catch (ArgumentOutOfRangeException e) when (e.GetType() == typeof(ArgumentOutOfRangeException))
        {
            string? name = (
                from method in typeof(ParallelHelper).GetMethods()
                where
                    method.Name == nameof(ParallelHelper.For2D) &&
                    method.IsGenericMethodDefinition
                let typeParams = method.GetGenericArguments()
                let normalParams = method.GetParameters()
                where
                    typeParams.Length == 1 &&
                    normalParams.Length == 4 &&
                    normalParams.All(p => p.ParameterType == typeof(int))
                select normalParams[0].Name).Single();

            Assert.AreEqual(e.ParamName, name);

            return;
        }

        Assert.Fail("Failed to raise correct exception");
    }

    [TestMethod]
    public void Test_ParallelHelper_ParameterName_ThrowArgumentOutOfRangeExceptionForLeftGreaterThanRight()
    {
        try
        {
            ParallelHelper.For2D<DummyAction2D>(0, 1, 1, 0);
        }
        catch (ArgumentOutOfRangeException e) when (e.GetType() == typeof(ArgumentOutOfRangeException))
        {
            string? name = (
                from method in typeof(ParallelHelper).GetMethods()
                where
                    method.Name == nameof(ParallelHelper.For2D) &&
                    method.IsGenericMethodDefinition
                let typeParams = method.GetGenericArguments()
                let normalParams = method.GetParameters()
                where
                    typeParams.Length == 1 &&
                    normalParams.Length == 4 &&
                    normalParams.All(p => p.ParameterType == typeof(int))
                select normalParams[2].Name).Single();

            Assert.AreEqual(e.ParamName, name);

            return;
        }

        Assert.Fail("Failed to raise correct exception");
    }

    /// <summary>
    /// A dummy type implementing <see cref="IAction"/>
    /// </summary>
    private readonly struct DummyAction : IAction
    {
        /// <inheritdoc/>
        public void Invoke(int i)
        {
        }
    }

    /// <summary>
    /// A dummy type implementing <see cref="IAction2D"/>
    /// </summary>
    private readonly struct DummyAction2D : IAction2D
    {
        /// <inheritdoc/>
        public void Invoke(int i, int j)
        {
        }
    }
}