public void WhenDocumentIsNotEmpty_GetImagesCount_ShouldReturnValidCount() { htmlService.Setup(f => f.GetDocument(It.IsAny <Uri>())).Returns(mockDocumentProvider.GetHtmlDocument_WithImages()); IContentParser parser = new ContentParser(htmlService.Object); var images = parser.GetImages(url); Assert.IsTrue(images.Count > 0, "Images count should not be 0"); }