Issue 13274: Make the pure python code for heapq more closely match the C implementation for an undefined corner case.
diff --git a/Lib/heapq.py b/Lib/heapq.py
index fcaca13..6a4e0f4 100644
--- a/Lib/heapq.py
+++ b/Lib/heapq.py
@@ -193,6 +193,8 @@
Equivalent to: sorted(iterable, reverse=True)[:n]
"""
+ if n < 0:
+ return []
it = iter(iterable)
result = list(islice(it, n))
if not result:
@@ -209,6 +211,8 @@
Equivalent to: sorted(iterable)[:n]
"""
+ if n < 0:
+ return []
if hasattr(iterable, '__len__') and n * 10 <= len(iterable):
# For smaller values of n, the bisect method is faster than a minheap.
# It is also memory efficient, consuming only n elements of space.