changeset: 80182:969069d464bc branch: 3.3 parent: 80180:0b5f00ccf907 user: Stefan Krah date: Fri Nov 02 17:49:22 2012 +0100 files: Doc/library/stdtypes.rst Lib/test/test_buffer.py Objects/memoryobject.c description: Issue #15814: Use hash function that is compatible with the equality definition from #15573. diff -r 0b5f00ccf907 -r 969069d464bc Doc/library/stdtypes.rst --- a/Doc/library/stdtypes.rst Fri Nov 02 14:44:20 2012 +0100 +++ b/Doc/library/stdtypes.rst Fri Nov 02 17:49:22 2012 +0100 @@ -2393,12 +2393,6 @@ .. versionchanged:: 3.3 One-dimensional memoryviews with formats 'B', 'b' or 'c' are now hashable. - .. note:: - Hashing of memoryviews with formats other than 'B', 'b' or 'c' as well - as hashing of multi-dimensional memoryviews is possible in version 3.3.0, - but will raise an error in 3.3.1 in order to be compatible with the new - memoryview equality definition. - :class:`memoryview` has several methods: .. method:: __eq__(exporter) diff -r 0b5f00ccf907 -r 969069d464bc Lib/test/test_buffer.py --- a/Lib/test/test_buffer.py Fri Nov 02 14:44:20 2012 +0100 +++ b/Lib/test/test_buffer.py Fri Nov 02 17:49:22 2012 +0100 @@ -3999,14 +3999,42 @@ m = memoryview(x) self.assertEqual(hash(m), hash(x)) + # equality-hash invariant + x = ndarray(list(range(12)), shape=[12], format='B') + a = memoryview(nd) + + y = ndarray(list(range(12)), shape=[12], format='b') + b = memoryview(nd) + + z = ndarray(list(bytes(chr(x), 'latin-1') for x in range(12)), + shape=[12], format='c') + c = memoryview(nd) + + if (a == b): + self.assertEqual(hash(a), hash(b)) + + if (a == c): + self.assertEqual(hash(a), hash(c)) + + if (b == c): + self.assertEqual(hash(b), hash(c)) + # non-byte formats nd = ndarray(list(range(12)), shape=[2,2,3], format='L') m = memoryview(nd) - self.assertEqual(hash(m), hash(nd.tobytes())) + self.assertRaises(ValueError, m.__hash__) nd = ndarray(list(range(-6, 6)), shape=[2,2,3], format='h') m = memoryview(nd) - self.assertEqual(hash(m), hash(nd.tobytes())) + self.assertRaises(ValueError, m.__hash__) + + nd = ndarray(list(range(12)), shape=[2,2,3], format='= L') + m = memoryview(nd) + self.assertRaises(ValueError, m.__hash__) + + nd = ndarray(list(range(-6, 6)), shape=[2,2,3], format='< h') + m = memoryview(nd) + self.assertRaises(ValueError, m.__hash__) def test_memoryview_release(self): diff -r 0b5f00ccf907 -r 969069d464bc Objects/memoryobject.c --- a/Objects/memoryobject.c Fri Nov 02 14:44:20 2012 +0100 +++ b/Objects/memoryobject.c Fri Nov 02 17:49:22 2012 +0100 @@ -2707,6 +2707,8 @@ if (self->hash == -1) { Py_buffer *view = &self->view; char *mem = view->buf; + Py_ssize_t ret; + char fmt; CHECK_RELEASED_INT(self); @@ -2715,6 +2717,12 @@ "cannot hash writable memoryview object"); return -1; } + ret = get_native_fmtchar(&fmt, view->format); + if (ret < 0 || !IS_BYTE_FORMAT(fmt)) { + PyErr_SetString(PyExc_ValueError, + "memoryview: hashing is restricted to formats 'B', 'b' or 'c'"); + return -1; + } if (view->obj != NULL && PyObject_Hash(view->obj) == -1) { /* Keep the original error message */ return -1;