public async Task GetErgodoxLayout(string layoutHashId, bool exist)
        {
            // Arrange
            ILayoutService layoutService = new LayoutService();

            // Act
            ErgodoxLayout response = null;

            if (exist)
            {
                response = await layoutService.GetErgodoxLayout(layoutHashId, "ergodox-ez", "latest");
            }
            else
            {
                await Assert.ThrowsAsync <ArgumentException>(() => layoutService.GetErgodoxLayout(layoutHashId, "ergodox-ez", "latest"));
            }

            // Assert
            if (exist)
            {
                Assert.NotNull(response);
                Assert.IsType <ErgodoxLayout>(response);
                Assert.NotNull(response.Revision);
                Assert.False(string.IsNullOrWhiteSpace(response.HashId));
                Assert.False(string.IsNullOrWhiteSpace(response.Title));
            }
        }
        public async Task GetErgodoxLayout_HashIdNull()
        {
            // Arrange
            ILayoutService layoutService = new LayoutService();

            // Act
            await Assert.ThrowsAsync <ArgumentNullException>(() => layoutService.GetErgodoxLayout("", "", ""));
        }