public async Task Translate_LessReturnDataSecond()
        {
            using (var session = new KeySession())
            {
                var fixture = new TranslateFixture();
                fixture.SetupTranslateLessResultSecond();
                var respository = new TranslatorRepository(fixture.TranslatorContext);
                // In the setup callback, I write Assert.
                var result = await respository.TranslateAsync(fixture.InputText, fixture.InputLanguage);

                Assert.Equal("", result);
            }
        }
        public async Task Translate_Normal()
        {
            using (var session = new KeySession())
            {
                var fixture     = new TranslateFixture();
                var ExpectedURL =
                    $"https://api.cognitive.microsofttranslator.com/translate?api-version=3.0&from=en&to={fixture.InputLanguage}";
                fixture.SetupTranslate(session.InputKey, ExpectedURL);
                var respository = new TranslatorRepository(fixture.TranslatorContext);
                // In the setup callback, I write Assert.
                var result = await respository.TranslateAsync(fixture.InputText, fixture.InputLanguage);

                Assert.Equal(fixture.ExpectedTranslatedText, result);
            }
        }
        public async Task Translate_Exception()
        {
            using (var session = new KeySession())
            {
                var fixture     = new TranslateFixture();
                var ExpectedURL =
                    $"https://api.cognitive.microsofttranslator.com/translate?api-version=3.0&from=en&to={fixture.InputLanguage}";
                fixture.SetupTranslateFailure(ExpectedURL);
                var respository = new TranslatorRepository(fixture.TranslatorContext);
                // In the setup callback, I write Assert.
                var ex = await Assert.ThrowsAsync <RestAPICallException>(async() =>
                                                                         await respository.TranslateAsync(fixture.InputText, fixture.InputLanguage)
                                                                         );

                Assert.Equal("InternalServerError", ex.StatusCode);
                Assert.Equal("Internal Server Error", ex.Message);
                Assert.Equal(ExpectedURL, ex.RequestMessage.RequestUri.ToString());
            }
        }