public async Task Given_A_PageSize_Should_Return_Most_Recent_Decks()
        {
            // Arrange
            var query = new MostRecentDecksQuery();

            _deckService.MostRecentDecks(Arg.Any <int>()).Returns(new MostRecentDecksResult {
                Decks = new List <DeckDetail>()
            });

            // Act
            var result = await _sut.Handle(query, CancellationToken.None);

            // Assert
            result.Decks.Should().BeNull();
        }
        public async Task Given_A_PageSize_Should_Invoke_MostRecentDecks_Once()
        {
            // Arrange
            var query = new MostRecentDecksQuery();

            _deckService.MostRecentDecks(Arg.Any <int>()).Returns(new MostRecentDecksResult
            {
                Decks = new List <DeckDetail>
                {
                    new DeckDetail
                    {
                        Id   = 234224,
                        Name = "Random Deck"
                    }
                }
            });

            // Act
            await _sut.Handle(query, CancellationToken.None);

            // Assert
            await _deckService.Received(1).MostRecentDecks(Arg.Any <int>());
        }