def test_last_index_initial(self):
"""
The 'last index' of an empty heap happens to be -1.
Hint: Easy to calculate if you know its size.
"""
h = MaxHeap()
self.assertEqual(-1, h._last_index())
def test_last_index_two(self):
"""
The last index of a heap with two elements is 1.
"""
h = MaxHeap()
h._data.append('fake')
h._data.append('fake')
self.assertEqual(1, h._last_index())
def test_last_index_42(self):
"""
The last index of a heap with forty-two elements is 41.
"""
h = MaxHeap()
for _ in range(42):
h._data.append('fake')
self.assertEqual(41, h._last_index())
def test_last_index_one(self):
"""
The last index of a heap with one element is 0.
Hint: Easy, if you know how to determine the last index of a list.
"""
h = MaxHeap()
h._data.append('fake')
self.assertEqual(0, h._last_index())
