public void GetNext()
{
Assert.AreEqual(0, _unitUnderTest.Count);
PageToCrawl page1 = new PageToCrawl(new Uri("http://a.com/1"));
PageToCrawl page2 = new PageToCrawl(new Uri("http://a.com/2"));
PageToCrawl page3 = new PageToCrawl(new Uri("http://a.com/3"));
_unitUnderTest.Add(page1);
_unitUnderTest.Add(page2);
_unitUnderTest.Add(page3);
Assert.AreEqual(3, _unitUnderTest.Count);
Assert.AreEqual(page1.Uri, _unitUnderTest.GetNext().Uri);
Assert.AreEqual(page2.Uri, _unitUnderTest.GetNext().Uri);
Assert.AreEqual(page3.Uri, _unitUnderTest.GetNext().Uri);
Assert.AreEqual(0, _unitUnderTest.Count);
}