public void Constructor_NullRssParser_ExceptionThrown()
{
// Fixture setup
IHttpClient httpClient = new HttpClientMock();
IRssParser rssParser = null;
IProgressIndicator progressIndicator = new ProgressIndicatorMock();
// Exercise system
// Verify outcome
Assert.ThrowsException<ArgumentNullException>
(() => new NewsFeedViewModel(httpClient, rssParser, progressIndicator));
// Teardown
}
public async Task GetLatestNewsAsync_CallWithoutParameters_ExceptionThrown()
{
// Fixture setup
IHttpClient httpClient = new HttpClientMock();
IRssParser rssParser = new RssParserMock();
IProgressIndicator progressIndicator = new ProgressIndicatorMock();
var viewModel = new NewsFeedViewModel(httpClient, rssParser, progressIndicator);
// Exercise system
var task = viewModel.GetLatestNewsAsync();
// Verify outcome
await AssertEx.ThrowsExceptionAsync<ArgumentException>(() => task);
// Teardown
}
public async Task GetLatestNewsAsync_MockForTwoNewsChannels_ValidItemCount()
{
// Fixture setup
var newsItem = new NewsItem("News item", "News text", DateTimeOffset.Now, null);
Func<string, NewsFeed> parsingFunc = rss => new NewsFeed(new[] { newsItem });
IHttpClient httpClient = new HttpClientMock();
IRssParser rssParser = new RssParserMock { CustomParsingFunction = parsingFunc };
IProgressIndicator progressIndicator = new ProgressIndicatorMock();
var viewModel = new NewsFeedViewModel(httpClient, rssParser, progressIndicator);
var newsChannel = new NewsChannel("News channel", new Uri("http://news.com/rss"));
var expectedNewsCount = 2;
// Exercise system
await viewModel.GetLatestNewsAsync(newsChannel, newsChannel);
// Verify outcome
Assert.AreEqual(viewModel.News.Count, expectedNewsCount);
// Teardown
}
public async Task GetLatestNewsAsync_MockForTwoNewsChannels_ValidNewsItemsSortingOrder()
{
// Fixture setup
var firstItem = new NewsItem("First item", "News text", DateTimeOffset.Now, null);
var secondItem = new NewsItem("Second item", "News text", firstItem.PublicationDate.AddSeconds(1), null);
var requestCounter = 0;
Func<string, NewsFeed> parsingFunc = rss =>
{
requestCounter++;
if (requestCounter == 1) return new NewsFeed(new[] { firstItem });
return new NewsFeed(new[] { secondItem });
};
IHttpClient httpClient = new HttpClientMock();
IRssParser rssParser = new RssParserMock { CustomParsingFunction = parsingFunc };
IProgressIndicator progressIndicator = new ProgressIndicatorMock();
var viewModel = new NewsFeedViewModel(httpClient, rssParser, progressIndicator);
var newsChannel = new NewsChannel("News channel", new Uri("http://news.com/rss"));
var expectedFirstItemTitle = secondItem.Title;
// Exercise system
await viewModel.GetLatestNewsAsync(newsChannel, newsChannel);
// Verify outcome
Assert.AreEqual(viewModel.News[0].Title, expectedFirstItemTitle);
// Teardown
}
public async Task GetLatestNewsAsync_NullNewsFeedFromNewsChannel_ExceptionThrown()
{
// Fixture setup
IHttpClient httpClient = new HttpClientMock();
IRssParser rssParser = new RssParserMock();
IProgressIndicator progressIndicator = new ProgressIndicatorMock();
var viewModel = new NewsFeedViewModel(httpClient, rssParser, progressIndicator);
var newsChannel = new NewsChannel("News channel", new Uri("http://news.com/rss"));
// Exercise system
var task = viewModel.GetLatestNewsAsync(newsChannel);
// Verify outcome
await AssertEx.ThrowsExceptionAsync<NullReferenceException>(() => task);
// Teardown
}
