Verifying a specific parameter with Moq

Question

public void SubmitMessagesToQueue_OneMessage_SubmitSuccessfully()
{
    var messageServiceClientMock = new Mock();
    var queueableMess         


        

Answer 1

If the verification logic is non-trivial, it will be messy to write a large lambda method (as your example shows). You could put all the test statements in a separate method, but I don't like to do this because it disrupts the flow of reading the test code.

Another option is to use a callback on the Setup call to store the value that was passed into the mocked method, and then write standard Assert methods to validate it. For example:

// Arrange
MyObject saveObject;
mock.Setup(c => c.Method(It.IsAny(), It.IsAny()))
        .Callback((i, obj) => saveObject = obj)
        .Returns("xyzzy");

// Act
// ...

// Assert
// Verify Method was called once only
mock.Verify(c => c.Method(It.IsAny(), It.IsAny()), Times.Once());
// Assert about saveObject
Assert.That(saveObject.TheProperty, Is.EqualTo(2));