def test_leaf_node(self):
"""
Test sum_internal on a leaf node.
"""
self.assertEqual(
sum_internal(Tree(1)), 0,
"Leaf nodes should " + "have 0 internal nodes to sum.")
def test_returns_int(self):
"""
Test sum_internal to make sure it returns an int.
"""
return_type = type(sum_internal(Tree(0, [Tree(1, [Tree(2)])])))
self.assertEqual(
return_type, int, "sum_internal should return type" +
"int, but instead returned type {}.".format(return_type))
def test_multiple_non_leaf_children(self):
"""
Test sum_internal on a tree containing only a root and its children
which are all subtrees with children.
"""
t = Tree(1, [Tree(2, [Tree(4), Tree(6)]), Tree(3, [Tree(5), Tree(7)])])
self.assertEqual(sum_internal(t), 6,
"All non-leaf nodes should be " + "summed together.")
def test_one_leaf_child(self):
"""
Test sum_internal on a tree containing only a root and its leaf child.
"""
t = Tree(1, [Tree(2)])
self.assertEqual(
sum_internal(t), 1, "Leaf nodes should not be " +
"included in the sum, while root nodes (with " +
"children) should.")
def test_multiple_leaf_children(self):
"""
Test sum_internal on a tree containing only a root and its children
which are all leaves.
"""
t = Tree(1, [Tree(2), Tree(3)])
self.assertEqual(
sum_internal(t), 1, "Leaf nodes should not be " +
"included in the sum, while root nodes (with " +
"children) should.")
def test_sum_internal(self, value, children):
"""
Test the correctness of sum_internal against the solution.
"""
(children_list, internal_sum) = make_children_list(children)
t = Tree(value, children_list)
if children_list:
internal_sum += value
actual = sum_internal(t)
self.assertEqual(actual, internal_sum,
("sum_internal on the Tree\n{}\nReturned {}" +
" instead of {}.").format(t.__repr__(), actual,
internal_sum))