Nunit: 支持 TestCaseSourceAttribute 的泛型类型参数

我正在研究一些使用泛型设计得更好的测试用例。 我正在尝试将TestCaseSource与许多不同的类型组合一起使用。

我遇到的问题是在我的测试中使用反射来调用我用于对象验证的通用测试方法。

[TestFixture]
public class SomeTests
{
    public static IEnumerable<TestCaseData> TestCases()
    {
        yield return
            new TestCaseData(
                typeof(Foo),
                typeof(Bar),
                Generator.Foo,
                Assertions.Foo);
        yield return
            new TestCaseData(
                typeof(Bar),
                typeof(Foo),
                Generator.Bar,
                Assertions.Bar);
    }

    [TestCaseSource(nameof(TestCases))]
    public void CheckSomeTypes(
        Type sourceType,
        Type destinationType,
        TSource source,
        Action<object, object> assert)
    {
        GetType()
            .GetMethod(nameof(CheckSomeTypesImpl), BindingFlags.Public | BindingFlags.Instance)
            .MakeGenericType(new[] { sourceType, destinationType })
            .Invoke(this, new object[] { source, assert });
    }

    public void CheckSomeTypesImpl<TSource, TDestination>(
        TSource source,
        Action<TSource, TDestination> assert)
    {
        var destination = Mapper.Map<TSource, TDestination>(source);

        // Assert are equiviliant
        assert(source, destination);
    }
}

但是，我相信以下设计可能会在这种情况下增加价值：

[TestFixture]
public class SomeTests
{
    public static IEnumerable<TestCaseData> TestCases()
    {
        yield return
            new TestCaseData(
                typeof(Foo),
                typeof(Bar),
                Generator.Foo,
                Assertions.Foo);
        yield return
            new TestCaseData(
                typeof(Bar),
                typeof(Foo),
                Generator.Bar,
                Assertions.Bar);
    }

    [TestCaseSource(nameof(TestCases))]
    public void CheckSomeTypes<TSource, TDestination>(
        TSource source,
        Action<TSource, TDestination> assert)
    {
        var destination = Mapper.Map<TSource, TDestination>(source);

        // Assert are equiviliant
        assert(source, destination);
    }
}

public class Foo
{
    public string Qux { get; set; }
}

public class Bar
{
    public string Qux { get; set; }
}

public static class Generator
{
    public static Foo Foo =>
        new Foo { Qux = "TestTestTest" };
    public static Bar Bar =>
        new Foo { Bar = "AnotherAnotherAnother" };
}

public static class Mapper
{
    // Generic mapper function
    public static TDestination Map<TSource, TDestination>(TSource source)
    {
        if (typeof(TSource) == typeof(Foo))
        {
            return Map((Foo) source);
        }

        if (typeof(TSource) == typeof(Bar))
        {
            return Map((Bar) source);
        }

        throw new NotImplementedException($"No mapping for {typeof(TSource).FullName}.");
    }

    public static Foo Map(Bar bar)
    {
        return new Foo { Qux = bar.Qux };
    }

    public static Bar Map(Foo foo)
    {
        return new Bar { Qux = foo.Qux };
    }
}

public static class Assertions
{
    public static Action<Foo, Bar> Foo =>
        (foo, bar) => Assert.AreEqual(foo.Qux, bar.Qux);
    public static Action<Bar, Foo> Bar =>
        (bar, foo) => Assert.AreEqual(bar.Qux, foo.Qux);
}

我在本地对TestCaseSourceAttribute进行了扩展以支持这一点。

这是开放的贡献吗？ 在创建 PR 之前，我想先阐明设计。