It checks that CSS renders correctly by taking screenshots of portions of a website and comparing them against known good screenshots. It also provides tools for testing calculated CSS values and the position of HTML elements.
This is what a Needle test case looks like:
from needle.cases import NeedleTestCase class BBCNewsTest(NeedleTestCase): def test_masthead(self): self.driver.get('http://www.bbc.co.uk/news/') self.assertScreenshot('#blq-mast', 'bbc-masthead')
This example checks for regressions in the appearance of the BBC's masthead.
Full documentation is on Read the Docs.