def test_heap_extracts(self):
heap = Heap()
heap.items = [-1, 0, 3, 5, 1]
self.assertEqual(heap.extract_min(), -1)
self.assertEqual(heap.items, [0, 1, 3, 5])
self.assertEqual(heap.extract_min(), 0)
self.assertEqual(heap.items, [1, 5, 3])
self.assertEqual(heap.extract_min(), 1)
self.assertEqual(heap.items, [3, 5])
self.assertEqual(heap.extract_min(), 3)
self.assertEqual(heap.items, [5])
self.assertEqual(heap.extract_min(), 5)
self.assertEqual(heap.items, [])
