Veryfying the key and value of the dictionary passed as parameter with Moq.It

In unit-tests, you mock out external dependencies. With Mock framework, you can verify that a correct value is passed into the dependency. Today, I had a case that a dictionary object is passed into the dictionary. I wasn’t sure how to verify that the value is correct, as what I wanted was just to check the dictionary has two keys and those keys have correct values.

Simply, I learned I can use Moq.It.Is…

The code is like this. It uses Moq and Machine.Specification.

public class When_you_verify_the_dictionary_has_certain_keys_and_values
    static Mock<IConsume> _consumer;
    static ConsumerUser _consumerUser;
    static string _username;
    static string _password;

    Establish context = () =>
            _username = "Dorothy";
            _password = "Perkins";
            _consumer = new Mock<IConsume>();
            _consumerUser = new ConsumerUser(_consumer.Object);

    Because it_consumes = () => _consumerUser.Consume(_username, _password);

    It should_have_username_and_password_in_the_input = () => 
        _consumer.Verify(d =>d.Consume(Moq.It.Is<Dictionary<string, string>>(
                dict => dict["username"] == "Dorothy" &&
                        dict["password"] == "Perkins")));

public interface IConsume
    void Consume(Dictionary<string, string> input);

public class ConsumerUser 
    private readonly IConsume _consume;

    public ConsumerUser(IConsume consume)
        _consume = consume;

    public void Consume(string username, string password)
        var pairs = new Dictionary<string, string>();
        pairs.Add("username", username);
        pairs.Add("password", password);


The above code is in github.