Add max heap version of heappush

Author: Yuting Liu

Lib/heapq.py

@@ -188,6 +188,11 @@ def _heappop_max(heap):
         return returnitem
     return lastelt
 
+def heappush_pop(heap, item):
+    """Maxheap version of a heappush."""
+    heap.append(item)
+    _siftdown_max(heap, 0, len(heap)-1)
+
 def _heapreplace_max(heap, item):
     """Maxheap version of a heappop followed by a heappush."""
     returnitem = heap[0]    # raises appropriate IndexError if heap is empty

Lib/test/test_heapq.py

@@ -14,7 +14,7 @@
 # _heapq.nlargest/nsmallest are saved in heapq._nlargest/_smallest when
 # _heapq is imported, so check them there
 func_names = ['heapify', 'heappop', 'heappush', 'heappushpop', 'heapreplace',
-              '_heappop_max', '_heapreplace_max', '_heapify_max']
+              '_heappop_max', '_heappush_max', '_heapreplace_max', '_heapify_max']
 
 class TestModules(TestCase):
     def test_py_functions(self):
@@ -160,6 +160,13 @@ def test_heappop_max(self):
         self.assertEqual(self.module._heappop_max(h), 3)
         self.assertEqual(self.module._heappop_max(h), 2)
 
+    def test_heappush_max(self):
+        h = [3, 2]
+        self.module._heappush_max(h, 3)
+        self.assertEqual(h[0], 3)
+        self.module._heappush_max(h, 5)
+        self.assertEqual(h[0], 5)
+
     def test_heapsort(self):
         # Exercise everything with repeated heapsort checks
         for trial in range(100):