def getElementsBy(start_node: ParentNode, cond: Callable[['Element'],
bool]) -> NodeList:
"""Return list of child elements of start_node which matches ``cond``.
``cond`` must be a function which gets a single argument ``Element``,
and returns boolean. If the node matches requested condition, ``cond``
should return True.
This searches all child elements recursively.
:arg ParentNode start_node:
:arg cond: Callable[[Element], bool]
:rtype: NodeList[Element]
"""
elements = []
for child in start_node.children:
if cond(child):
elements.append(child)
elements.extend(child.getElementsBy(cond))
return NodeList(elements)
class TestNodeList(TestCase):
def setUp(self):
super().setUp()
self.nl = NodeList(list(range(3)))
def test_length(self):
self.assertEqual(self.nl.length, 3)
self.assertEqual(len(self.nl), 3)
def test_index_access(self):
self.assertEqual(self.nl[1], 1)
self.assertEqual(self.nl[-1], 2)
self.assertEqual(self.nl[1:2], [1])
with self.assertRaises(IndexError):
self.nl[5]
def test_item(self):
self.assertEqual(self.nl.item(1), 1)
self.assertEqual(self.nl.item(-1), None)
self.assertEqual(self.nl.item(5), None)
with self.assertRaises(TypeError):
self.nl.item(slice(1, 2))
def test_contains(self):
self.assertTrue(1 in self.nl)
self.assertFalse(5 in self.nl)
def test_iteration(self):
l = [0, 1, 2]
for n in self.nl:
self.assertEqual(n, l.pop(0))
l = [2, 1, 0]
for n in reversed(self.nl):
self.assertEqual(n, l.pop(0))
def test_index(self):
self.assertEqual(self.nl.index(0), 0)
self.assertEqual(self.nl.index(1), 1)
self.assertEqual(self.nl.index(2), 2)
def setUp(self):
super().setUp()
self.nl = NodeList(list(range(3)))
def selectedOptions(self) -> NodeList:
"""Return all selected option nodes."""
return NodeList(list(opt for opt in self.options if opt.selected))