SimpleInteractionVerificationUsingMock.cs

[Fact]
public async Task ShouldGenerateAccessTokenIfUserIsRegistered()
{
    // arrange
    var membershipRepositoryMock = new Mock<IMembershipRepository>();
    var registeredUser = new RegisteredUser("firstName", "lastName");

    membershipRepositoryMock
        .Setup(x => x.Verify(It.IsAny<UserLogin>()))
        .ReturnsAsync(registeredUser);

    var tokenGenerator = new Mock<IJwtTokenGenerator>();
    tokenGenerator
        .Setup(x => x.GenerateAccessToken(
            It.IsAny<string>(),
            It.IsAny<Claim[]>()))
        .Returns(It.IsAny<string>())
        .Verifiable();

    var authController = new AuthController(
        membershipRepositoryMock.Object,
        tokenGenerator.Object);
        
    // act
    var response = await authController.Login(
        new UserLoginRequest
        {
            Username = "unregistered",
            Password = "pass1"
        });
        
    // assert
    tokenGenerator.Verify(x =>
        x.GenerateAccessToken(
            registeredUser.Fullname,
            It.IsAny<Claim[]>()),
            Times.Once);
}