public async Task KeyPhrasesResult() { var httpResult = new HttpOperationResponse <KeyPhraseBatchResult>(); httpResult.Body = new KeyPhraseBatchResult(new List <KeyPhraseBatchResultItem>(new List <KeyPhraseBatchResultItem>() { new KeyPhraseBatchResultItem(new List <string>() { "phrase1", "phrase2" }) }), null); clientMock.Setup(s => s.KeyPhrasesWithHttpMessagesAsync(It.IsAny <MultiLanguageBatchInput>(), null, CancellationToken.None)).ReturnsAsync(httpResult); TextAnalyticsService textAnalyticsService = new TextAnalyticsService(clientMock.Object, configurationMock.Object, loggerMock.Object); var result = await textAnalyticsService.KeyPhrasesAsync(It.IsAny <string>()); clientMock.Verify(s => s.KeyPhrasesWithHttpMessagesAsync(It.IsAny <MultiLanguageBatchInput>(), null, CancellationToken.None), Times.Once); Assert.IsType <List <string> >(result); Assert.Equal("phrase1", result[0]); Assert.Equal("phrase2", result[1]); }