def test_descendents(self):
a = Item(1, 'tag', 'a')
b = Item(2, 'tag', 'b')
c = Item(3, 'tag', 'c')
d = Item(4, 'tag', 'd')
a.add_child(b)
a.add_child(c)
c.add_child(d)
width_first_items = [a, b, c, d]
depth_first_items = [(a, 0), (c, 1), (d, 2), (b, 1)]
actual_width_first_items = [x[0] for x in a.descendents()]
actual_depth_first_items = list(a.descendents(width_first=False))
self.assertEqual(actual_width_first_items, width_first_items)
self.assertEqual(actual_depth_first_items, depth_first_items)
# test that c and d are descendents of a. and can break on that.
searched_descendents = list()
for item, level in a.descendents():
if item == b:
break
searched_descendents.append(item)
self.assertTrue(len(searched_descendents) < 4)
# test that c is a descendents of a. and can break on that.
searched_descendents = list()
for item, level in a.descendents():
if item == c:
break
searched_descendents.append(item)
self.assertTrue(len(searched_descendents) < 4)
def test_hierarchy(self):
me = Item(1, 'tag', 'me')
la = Item(2, 'tag', 'la')
me2 = Item(3, 'tag', 'me')
self.assertTrue(me == me2)
self.assertEqual(me2, me)
me.add_child(la)
self.assertEqual(list(me.child_items()), [la])
self.assertEqual([x for x in la.parent_items()], [me])
def test_no_cycles(self):
""" Assert that an item can not be added as its own descendent. """
a = Item(1, 'tag', 'a')
b = Item(2, 'tag', 'b')
c = Item(3, 'tag', 'c')
d = Item(4, 'tag', 'd')
a.add_child(b)
a.add_child(c)
c.add_child(d)
self.assertRaises(ItemError, lambda: a.add_child(a))
self.assertRaises(ItemError, b.add_child, a)
self.assertRaises(ItemError, d.add_child, a)
