public AddedPayeSchemeEventHandlerTestsFixture()
        {
            Context = new Mock <IMessageHandlerContext>();

            Event = new AddedPayeSchemeEvent {
                AccountId = 12345, PayeRef = "ABC/1234565"
            };

            Handler = new AddedPayeSchemeEventHandler();
        }
        public async Task Handle_WhenHandlingAddedPayeSchemeEvent_ThenShouldSendAddedPayeSchemeCommand(
            TestableMessageHandlerContext context,
            [Frozen] Mock <IMediator> mediator,
            AddedPayeSchemeEventHandler handler,
            AddedPayeSchemeEvent message)
        {
            //arrange

            //act
            await handler.Handle(message, context);

            //assert
            mediator.Verify(s => s.Send(It.Is <AddedPayeSchemeCommand>(c =>
                                                                       c.AccountId == message.AccountId &&
                                                                       c.Aorn == message.Aorn &&
                                                                       c.CorrelationId == message.CorrelationId &&
                                                                       c.PayeRef == message.PayeRef &&
                                                                       c.SchemeName == message.SchemeName &&
                                                                       c.UserName == message.UserName &&
                                                                       c.UserRef == message.UserRef), It.IsAny <CancellationToken>()));
        }