Parameter types are ignored when matching an invoked generic method against setups

[stakx]

Code to reproduce:

public interface IX
{
	void M<T>(Exception arg);
	void M<T>(Uri arg);
}

[Fact]
public void Test()
{
    var exceptionSetupInvoked = false;
    var mock = new Mock<IX>();
    mock.Setup(m => m.M<object>((Exception)null)).Callback(() => exceptionSetupInvoked = true);
    mock.Setup(m => m.M<object>((Uri)null)).Callback(() => throw new Exception("Wrong setup matched."));

    mock.Object.M<int>((Exception)null);

    Assert.True(exceptionSetupInvoked);
}

Expected outcome:

The test should succeed.

Actual outcome:

The test throws the "Wrong setup matched." exception.

Further information:

While the concrete generic arguments in the above test are irrelevant (since Moq matches generic arguments by assignment compatibility), the presence of generic type parameters are central to this issue as they disable any parameter type checks that would otherwise happen. Note the else in the following:

https://github.com/moq/moq4/blob/3868424bac43b2c08342b363eb6c511fdbc982ea/src/Moq/InvocationShape.cs#L113-L126

As a side note, setup order also matters for this test.

[stakx]

Here are the test cases to be added to the regression test suite.

public class Issue903
{
    public interface IX
    {
        void Method<T>(bool arg);
        void Method<T>(int arg);
    }

    private readonly Mock<IX> mock;

    public Issue903()
    {
        this.mock = new Mock<IX>();
    }

    [Fact]
    public void Bool_method_was_setup_first__when_bool_method_invoked__bool_method_setup_should_be_matched()
    {
        var boolMethodInvoked = false;
        this.SetupBoolMethod(() => boolMethodInvoked = true);
        this.SetupIntMethod(() => throw new Exception("Wrong method called."));

        this.InvokeBoolMethod();

        Assert.True(boolMethodInvoked);
    }

    [Fact]
    public void Bool_method_was_setup_last__when_bool_method_invoked__bool_method_setup_should_be_matched()
    {
        var boolMethodInvoked = false;
        this.SetupIntMethod(() => throw new Exception("Wrong method called."));
        this.SetupBoolMethod(() => boolMethodInvoked = true);

        this.InvokeBoolMethod();

        Assert.True(boolMethodInvoked);
    }

    [Fact]
    public void Int_method_was_setup_last__when_int_method_invoked__int_method_setup_should_be_matched()
    {
        bool intMethodInvoked = false;
        this.SetupBoolMethod(() => throw new Exception("Wrong method called."));
        this.SetupIntMethod(() => intMethodInvoked = true);

        this.InvokeIntMethod();

        Assert.True(intMethodInvoked);
    }

    [Fact]
    public void Int_method_was_setup_first__when_int_method_invoked__int_method_setup_should_be_matched()
    {
        bool intMethodInvoked = false;
        this.SetupIntMethod(() => intMethodInvoked = true);
        this.SetupBoolMethod(() => throw new Exception("Wrong method called."));

        this.InvokeIntMethod();

        Assert.True(intMethodInvoked);
    }

    private void InvokeBoolMethod()
    {
        this.mock.Object.Method<bool>(default(bool));
    }

    private void InvokeIntMethod()
    {
        this.mock.Object.Method<int>(default(int));
    }

    private void SetupBoolMethod(Action callback)
    {
        mock.Setup(m => m.Method<object>((bool)It.IsAny<object>())).Callback(callback);
    }

    private void SetupIntMethod(Action callback)
    {
        this.mock.Setup(m => m.Method<object>((int)It.IsAny<object>())).Callback(callback);
    }
}