Issue 10110: Let Queue.put recognize a full queue when the maxsize parameter has been reduced.
diff --git a/Lib/queue.py b/Lib/queue.py
index f051f1c..bee7ed4 100644
--- a/Lib/queue.py
+++ b/Lib/queue.py
@@ -110,14 +110,14 @@
def full(self):
"""Return True if the queue is full, False otherwise (not reliable!).
- This method is likely to be removed at some point. Use qsize() == n
+ This method is likely to be removed at some point. Use qsize() >= n
as a direct substitute, but be aware that either approach risks a race
condition where a queue can shrink before the result of full() or
qsize() can be used.
"""
self.mutex.acquire()
- n = 0 < self.maxsize == self._qsize()
+ n = 0 < self.maxsize <= self._qsize()
self.mutex.release()
return n
@@ -136,16 +136,16 @@
try:
if self.maxsize > 0:
if not block:
- if self._qsize() == self.maxsize:
+ if self._qsize() >= self.maxsize:
raise Full
elif timeout is None:
- while self._qsize() == self.maxsize:
+ while self._qsize() >= self.maxsize:
self.not_full.wait()
elif timeout < 0:
raise ValueError("'timeout' must be a positive number")
else:
endtime = _time() + timeout
- while self._qsize() == self.maxsize:
+ while self._qsize() >= self.maxsize:
remaining = endtime - _time()
if remaining <= 0.0:
raise Full
diff --git a/Lib/test/test_queue.py b/Lib/test/test_queue.py
index 0c8093a..5cef90c 100644
--- a/Lib/test/test_queue.py
+++ b/Lib/test/test_queue.py
@@ -216,6 +216,18 @@
with self.assertRaises(queue.Empty):
q.get_nowait()
+ def test_shrinking_queue(self):
+ # issue 10110
+ q = self.type2test(3)
+ q.put(1)
+ q.put(2)
+ q.put(3)
+ with self.assertRaises(queue.Full):
+ q.put_nowait(4)
+ self.assertEqual(q.qsize(), 3)
+ q.maxsize = 2 # shrink the queue
+ with self.assertRaises(queue.Full):
+ q.put_nowait(4)
class QueueTest(BaseQueueTest):
type2test = queue.Queue