The bufsize argument to Popen() should accept None meaning the default (0).

diff --git a/Lib/subprocess.py b/Lib/subprocess.py
index 051f2d46fb77cf3f7cad79beec9bf0f504d6e4a4..1ae74268a27c1493dc07fe431fc967525ee102a8 100644 (file)
--- a/Lib/subprocess.py
+++ b/Lib/subprocess.py
@@ -465,6 +465,8 @@ class Popen(object):
         _cleanup()
 
         self._child_created = False
+        if bufsize is None:
+            bufsize = 0  # Restore default
         if not isinstance(bufsize, int):
             raise TypeError("bufsize must be an integer")
 

diff --git a/Lib/test/test_subprocess.py b/Lib/test/test_subprocess.py
index ec004bf5c53b780e55a9040b68ffb515833ec1dd..b44e83a57b4dbffdb49e44d0ef71492c52219af9 100644 (file)
--- a/Lib/test/test_subprocess.py
+++ b/Lib/test/test_subprocess.py
@@ -455,6 +455,14 @@ class ProcessTestCase(unittest.TestCase):
         else:
             self.fail("Expected TypeError")
 
+    def test_bufsize_is_none(self):
+        # bufsize=None should be the same as bufsize=0.
+        p = subprocess.Popen([sys.executable, "-c", "pass"], None)
+        self.assertEqual(p.wait(), 0)
+        # Again with keyword arg
+        p = subprocess.Popen([sys.executable, "-c", "pass"], bufsize=None)
+        self.assertEqual(p.wait(), 0)
+
     #
     # POSIX tests
     #