public void NonImageContentForSameHost_ThrowsCachedHttpRequestException()
{
var host = "host";
var url = new Uri("https://" + host + "/image");
var contentType = "text/html";
var expectMessage1 = ImageDownloader.NonImageContentExceptionMessage(contentType);
var expectMessage2 = ImageDownloader.CachedExceptionMessage(host);
var httpClient = Substitute.For <IHttpClient>();
var response = Substitute.For <IResponse>();
response.StatusCode.Returns(HttpStatusCode.OK);
response.ContentType.Returns(contentType);
httpClient.Send(null, default(CancellationToken)).ReturnsForAnyArgs(Task.FromResult(response));
var target = new ImageDownloader(new Lazy <IHttpClient>(() => httpClient));
var ex1 = Assert.CatchAsync <HttpRequestException>(async() => await target.DownloadImageBytes(url));
var ex2 = Assert.CatchAsync <HttpRequestException>(async() => await target.DownloadImageBytes(url));
Assert.That(ex1?.Message, Is.EqualTo(expectMessage1));
Assert.That(ex2?.Message, Is.EqualTo(expectMessage2));
}