def test_inserting_three_nodes_in_descending_line_then_root_should_be_black():
object_under_test = RedBlackTree()
object_under_test.insert(3)
object_under_test.insert(2)
object_under_test.insert(1)
assert object_under_test.get_root().is_red is False
def test_deleting_only_node_should_leave_the_tree_empty():
object_under_test = RedBlackTree()
object_under_test.insert(22)
object_under_test.delete(22)
assert not object_under_test.traverse_preorder()
def test_inserting_three_nodes_in_ascending_line_then_right_child_value_should_be_highest(
):
object_under_test = RedBlackTree()
object_under_test.insert(1)
object_under_test.insert(2)
object_under_test.insert(3)
assert object_under_test.get_root().right.value == 3
def test_inserting_three_nodes_in_ascending_line_then_root_value_should_be_in_the_middle(
):
object_under_test = RedBlackTree()
object_under_test.insert(1)
object_under_test.insert(2)
object_under_test.insert(3)
assert object_under_test.get_root().value == 2
def test_search_on_a_tree_containing_given_value_should_return_node_with_the_value(
):
object_under_test = RedBlackTree()
object_under_test.insert(8)
result = object_under_test.search(8)
assert result.value == 8
def test_given_elements_then_traverse_preorder_should_return_elements_in_preorder_with_parents_first(
input_elements, expected_output):
object_under_test = RedBlackTree()
for ele in input_elements:
object_under_test.insert(value=ele)
assert expected_output == object_under_test.traverse_preorder()
def test_inserting_root_and_two_children_then_root_value_should_be_in_the_middle(
):
object_under_test = RedBlackTree()
object_under_test.insert(2)
object_under_test.insert(1)
object_under_test.insert(3)
assert object_under_test.get_root().value == 2
def test_inserting_three_nodes_in_descending_line_then_right_child_should_be_red(
):
object_under_test = RedBlackTree()
object_under_test.insert(3)
object_under_test.insert(2)
object_under_test.insert(1)
assert object_under_test.get_root().right.is_red is True
def test_inserting_three_nodes_in_descending_line_then_left_child_value_should_be_lowest(
):
object_under_test = RedBlackTree()
object_under_test.insert(3)
object_under_test.insert(2)
object_under_test.insert(1)
assert object_under_test.get_root().left.value == 1
def test_deleting_nonexistent_value_should_raise():
object_under_test = RedBlackTree()
object_under_test.insert(44)
nonexistent_value = 22
with pytest.raises(ValueNotFoundInTreeError) as err:
object_under_test.delete(nonexistent_value)
assert f"{nonexistent_value}" in str(err)
def test_inserting_duplicated_value_should_raise_an_error():
object_under_test = RedBlackTree()
duplicated_elem = 8
object_under_test.insert(duplicated_elem)
with pytest.raises(DuplicatedValueInTreeError) as err:
object_under_test.insert(duplicated_elem)
assert f"{duplicated_elem}" in str(err)
def test_inserting_root_and_two_children_then_right_child_should_be_red():
object_under_test = RedBlackTree()
object_under_test.insert(15)
object_under_test.insert(8)
object_under_test.insert(33)
assert object_under_test.get_root().right.is_red is True
def test_inserting_root_and_two_children_then_right_child_value_should_be_highest(
):
object_under_test = RedBlackTree()
object_under_test.insert(15)
object_under_test.insert(8)
object_under_test.insert(33)
assert object_under_test.get_root().right.value == 33
def test_given_one_node_then_is_empty_should_return_false():
object_under_test = RedBlackTree()
object_under_test.insert(15)
assert not object_under_test.is_empty()
