http://hg.python.org/cpython/rev/c499cc2c4a06 changeset: 92270:c499cc2c4a06 user: Antoine Pitrou <solipsis@pitrou.net> date: Sat Aug 30 00:37:18 2014 +0200 summary: Issue #22098: ctypes' BigEndianStructure and LittleEndianStructure now define an empty __slots__ so that subclasses don't always get an instance dict. Patch by Claudiu Popa. files: Lib/ctypes/_endian.py | 2 ++ Lib/ctypes/test/test_byteswap.py | 20 ++++++++++++++++++++ Misc/NEWS | 4 ++++ 3 files changed, 26 insertions(+), 0 deletions(-) diff --git a/Lib/ctypes/_endian.py b/Lib/ctypes/_endian.py --- a/Lib/ctypes/_endian.py +++ b/Lib/ctypes/_endian.py @@ -45,6 +45,7 @@ class BigEndianStructure(Structure, metaclass=_swapped_meta): """Structure with big endian byte order""" + __slots__ = () _swappedbytes_ = None elif sys.byteorder == "big": @@ -53,6 +54,7 @@ BigEndianStructure = Structure class LittleEndianStructure(Structure, metaclass=_swapped_meta): """Structure with little endian byte order""" + __slots__ = () _swappedbytes_ = None else: diff --git a/Lib/ctypes/test/test_byteswap.py b/Lib/ctypes/test/test_byteswap.py --- a/Lib/ctypes/test/test_byteswap.py +++ b/Lib/ctypes/test/test_byteswap.py @@ -22,6 +22,26 @@ setattr(bits, "i%s" % i, 1) dump(bits) + def test_slots(self): + class BigPoint(BigEndianStructure): + __slots__ = () + _fields_ = [("x", c_int), ("y", c_int)] + + class LowPoint(LittleEndianStructure): + __slots__ = () + _fields_ = [("x", c_int), ("y", c_int)] + + big = BigPoint() + little = LowPoint() + big.x = 4 + big.y = 2 + little.x = 2 + little.y = 4 + with self.assertRaises(AttributeError): + big.z = 42 + with self.assertRaises(AttributeError): + little.z = 24 + def test_endian_short(self): if sys.byteorder == "little": self.assertIs(c_short.__ctype_le__, c_short) diff --git a/Misc/NEWS b/Misc/NEWS --- a/Misc/NEWS +++ b/Misc/NEWS @@ -124,6 +124,10 @@ Library ------- +- Issue #22098: ctypes' BigEndianStructure and LittleEndianStructure now + define an empty __slots__ so that subclasses don't always get an instance + dict. Patch by Claudiu Popa. + - Issue #22185: Fix an occasional RuntimeError in threading.Condition.wait() caused by mutation of the waiters queue without holding the lock. Patch by Doug Zongker. -- Repository URL: http://hg.python.org/cpython