def test_place_before(self):
from cocktail.html.element import Element
parent = Element()
child1 = Element()
parent.append(child1)
child2 = Element()
child2.place_before(child1)
self.assertTrue(child2.parent is parent)
self.assertEqual(parent.children, [child2, child1])
child3 = Element()
child3.place_before(child1)
self.assertTrue(child3.parent is parent)
self.assertEqual(parent.children, [child2, child3, child1])
child3.place_before(child2)
self.assertTrue(child3.parent is parent)
self.assertEqual(parent.children, [child3, child2, child1])
def place_before_root():
sibling = Element()
e = Element()
e.place_before(sibling)
