Resolve issue 4449: AssertionError in mp_benchmarks.py
diff --git a/Doc/library/multiprocessing.rst b/Doc/library/multiprocessing.rst
index 72ac38e..fe54f9b 100644
--- a/Doc/library/multiprocessing.rst
+++ b/Doc/library/multiprocessing.rst
@@ -880,7 +880,7 @@
It is possible to create shared objects using shared memory which can be
inherited by child processes.
-.. function:: Value(typecode_or_type[, *args, lock]])
+.. function:: Value(typecode_or_type, *args[, lock])
Return a :mod:`ctypes` object allocated from shared memory. By default the
return value is actually a synchronized wrapper for the object.
@@ -962,7 +962,7 @@
*typecode_or_type* determines the type of the returned object: it is either a
ctypes type or a one character typecode of the kind used by the :mod:`array`
- module. */*args* is passed on to the constructor for the type.
+ module. *\*args* is passed on to the constructor for the type.
Note that setting and getting the value is potentially non-atomic -- use
:func:`Value` instead to make sure that access is automatically synchronized
@@ -972,7 +972,7 @@
attributes which allow one to use it to store and retrieve strings -- see
documentation for :mod:`ctypes`.
-.. function:: Array(typecode_or_type, size_or_initializer[, *args[, lock]])
+.. function:: Array(typecode_or_type, size_or_initializer, *args[, lock])
The same as :func:`RawArray` except that depending on the value of *lock* a
process-safe synchronization wrapper may be returned instead of a raw ctypes
diff --git a/Lib/multiprocessing/sharedctypes.py b/Lib/multiprocessing/sharedctypes.py
index 0054ff1..76b5e94 100644
--- a/Lib/multiprocessing/sharedctypes.py
+++ b/Lib/multiprocessing/sharedctypes.py
@@ -69,9 +69,12 @@
if kwds:
raise ValueError('unrecognized keyword argument(s): %s' % kwds.keys())
obj = RawValue(typecode_or_type, *args)
- if lock is None:
+ if lock is False:
+ return obj
+ if lock in (True, None):
lock = RLock()
- assert hasattr(lock, 'acquire')
+ if not hasattr(lock, 'acquire'):
+ raise AttributeError("'%r' has no method 'acquire'" % lock)
return synchronized(obj, lock)
def Array(typecode_or_type, size_or_initializer, **kwds):
@@ -82,9 +85,12 @@
if kwds:
raise ValueError('unrecognized keyword argument(s): %s' % kwds.keys())
obj = RawArray(typecode_or_type, size_or_initializer)
- if lock is None:
+ if lock is False:
+ return obj
+ if lock in (True, None):
lock = RLock()
- assert hasattr(lock, 'acquire')
+ if not hasattr(lock, 'acquire'):
+ raise AttributeError("'%r' has no method 'acquire'" % lock)
return synchronized(obj, lock)
def copy(obj):
diff --git a/Lib/test/test_multiprocessing.py b/Lib/test/test_multiprocessing.py
index b0746e9..2daff7e 100644
--- a/Lib/test/test_multiprocessing.py
+++ b/Lib/test/test_multiprocessing.py
@@ -829,10 +829,16 @@
obj3 = val3.get_obj()
self.assertEqual(lock, lock3)
- arr4 = self.RawValue('i', 5)
+ arr4 = self.Value('i', 5, lock=False)
self.assertFalse(hasattr(arr4, 'get_lock'))
self.assertFalse(hasattr(arr4, 'get_obj'))
+ self.assertRaises(AttributeError, self.Value, 'i', 5, lock='navalue')
+
+ arr5 = self.RawValue('i', 5)
+ self.assertFalse(hasattr(arr5, 'get_lock'))
+ self.assertFalse(hasattr(arr5, 'get_obj'))
+
class _TestArray(BaseTestCase):
@@ -887,9 +893,15 @@
obj3 = arr3.get_obj()
self.assertEqual(lock, lock3)
- arr4 = self.RawArray('i', range(10))
+ arr4 = self.Array('i', range(10), lock=False)
self.assertFalse(hasattr(arr4, 'get_lock'))
self.assertFalse(hasattr(arr4, 'get_obj'))
+ self.assertRaises(AttributeError,
+ self.Array, 'i', range(10), lock='notalock')
+
+ arr5 = self.RawArray('i', range(10))
+ self.assertFalse(hasattr(arr5, 'get_lock'))
+ self.assertFalse(hasattr(arr5, 'get_obj'))
#
#
diff --git a/Misc/NEWS b/Misc/NEWS
index 4c71db1..f333a92 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -137,6 +137,9 @@
Library
-------
+- Issue #4449: AssertionError in mp_benchmarks.py, caused by an underlying issue
+ in sharedctypes.py.
+
- Issue #1225107: inspect.isclass() returned True for instances with a custom
__getattr__.