Manually merge r68096,68189 from 3.0 branch.
diff --git a/Lib/heapq.py b/Lib/heapq.py
index 380fe12..2d34046 100644
--- a/Lib/heapq.py
+++ b/Lib/heapq.py
@@ -354,9 +354,12 @@
Equivalent to: sorted(iterable, key=key)[:n]
"""
+ if key is None:
+ it = zip(iterable, count()) # decorate
+ result = _nsmallest(n, it)
+ return list(map(itemgetter(0), result)) # undecorate
in1, in2 = tee(iterable)
- keys = in1 if key is None else map(key, in1)
- it = zip(keys, count(), in2) # decorate
+ it = zip(map(key, in1), count(), in2) # decorate
result = _nsmallest(n, it)
return list(map(itemgetter(2), result)) # undecorate
@@ -366,9 +369,12 @@
Equivalent to: sorted(iterable, key=key, reverse=True)[:n]
"""
+ if key is None:
+ it = zip(iterable, map(neg, count())) # decorate
+ result = _nlargest(n, it)
+ return list(map(itemgetter(0), result)) # undecorate
in1, in2 = tee(iterable)
- keys = in1 if key is None else map(key, in1)
- it = zip(keys, map(neg, count()), in2) # decorate
+ it = zip(map(key, in1), map(neg, count()), in2) # decorate
result = _nlargest(n, it)
return list(map(itemgetter(2), result)) # undecorate