在 Moq 中验证时允许 *any* 参数值？

Question

I'm verifying that a method was called with Moq, but it's quite a complex method signature and I just care about the value of one particular argument. I know Moq has It.IsAny<T>() , but even then you still have to specify what type the argument should be. Is there a way to just say "I don't care what was passed as this parameter, in terms of type OR value"?

Answer 1

There isn't a way to do what you're asking, because the Setup argument is an expression that represents strongly-typed C#. For example, consider the following approach:

void Main()
{
    Setup(() => Foo(Any()));
}

void Setup(Expression<Action> expression)
{
}

void Foo(int i)
{
}

object Any() 
{
    throw new NotImplementedException();
}

This code doesn't compile, because Any() returns an object and Foo() requires an int argument.

If we try to change Any() to return dynamic :

dynamic Any() {
    throw new NotImplementedException();
}

This produces the following error:

CS1963 An expression tree may not contain a dynamic operation

There's simply no way do make this expression generation work for every possible type without requiring a generic argument.

Answer 2

As @StriplingWarrior mentioned you've got to specify the arguments when using Verify .

However Moq does provide the Invocations sequence (unsure what version it was introduced, YMMV) so it is possible to basically do what you're asking.

For the following interface:

public interface IFoo
{
    public void Sum(int a, int b, out int sum);
}

... the following will assert that the Sum method was invoked once - without specifying any parameters.

var fooMock = new Mock<IFoo>();
var foo = fooMock.Object;

foo.Sum(1, 2, out var sum);

Assert.That(fooMock.Invocations.Count(x => x.Method.Name.Equals(nameof(IFoo.Sum))), Is.EqualTo(1));

Each invocation entry has the method, arguments etc so you can build complex matches.