cpython/Lib/test/test_memoryview.py

378 lines
12 KiB
Python

"""Unit tests for the memoryview
XXX We need more tests! Some tests are in test_bytes
"""
import unittest
import sys
import gc
import weakref
import array
from test import test_support
import io
import copy
import pickle
class AbstractMemoryTests:
source_bytes = b"abcdef"
@property
def _source(self):
return self.source_bytes
@property
def _types(self):
return filter(None, [self.ro_type, self.rw_type])
def check_getitem_with_type(self, tp):
item = self.getitem_type
b = tp(self._source)
oldrefcount = sys.getrefcount(b)
m = self._view(b)
self.assertEqual(m[0], item(b"a"))
self.assertIsInstance(m[0], bytes)
self.assertEqual(m[5], item(b"f"))
self.assertEqual(m[-1], item(b"f"))
self.assertEqual(m[-6], item(b"a"))
# Bounds checking
self.assertRaises(IndexError, lambda: m[6])
self.assertRaises(IndexError, lambda: m[-7])
self.assertRaises(IndexError, lambda: m[sys.maxsize])
self.assertRaises(IndexError, lambda: m[-sys.maxsize])
# Type checking
self.assertRaises(TypeError, lambda: m[None])
self.assertRaises(TypeError, lambda: m[0.0])
self.assertRaises(TypeError, lambda: m["a"])
m = None
self.assertEqual(sys.getrefcount(b), oldrefcount)
def test_getitem(self):
for tp in self._types:
self.check_getitem_with_type(tp)
def test_iter(self):
for tp in self._types:
b = tp(self._source)
m = self._view(b)
self.assertEqual(list(m), [m[i] for i in range(len(m))])
def test_repr(self):
for tp in self._types:
b = tp(self._source)
m = self._view(b)
self.assertIsInstance(m.__repr__(), str)
def test_setitem_readonly(self):
if not self.ro_type:
self.skipTest("no read-only type to test")
b = self.ro_type(self._source)
oldrefcount = sys.getrefcount(b)
m = self._view(b)
def setitem(value):
m[0] = value
self.assertRaises(TypeError, setitem, b"a")
self.assertRaises(TypeError, setitem, 65)
self.assertRaises(TypeError, setitem, memoryview(b"a"))
m = None
self.assertEqual(sys.getrefcount(b), oldrefcount)
def test_setitem_writable(self):
if not self.rw_type:
self.skipTest("no writable type to test")
tp = self.rw_type
b = self.rw_type(self._source)
oldrefcount = sys.getrefcount(b)
m = self._view(b)
m[0] = tp(b"0")
self._check_contents(tp, b, b"0bcdef")
m[1:3] = tp(b"12")
self._check_contents(tp, b, b"012def")
m[1:1] = tp(b"")
self._check_contents(tp, b, b"012def")
m[:] = tp(b"abcdef")
self._check_contents(tp, b, b"abcdef")
# Overlapping copies of a view into itself
m[0:3] = m[2:5]
self._check_contents(tp, b, b"cdedef")
m[:] = tp(b"abcdef")
m[2:5] = m[0:3]
self._check_contents(tp, b, b"ababcf")
def setitem(key, value):
m[key] = tp(value)
# Bounds checking
self.assertRaises(IndexError, setitem, 6, b"a")
self.assertRaises(IndexError, setitem, -7, b"a")
self.assertRaises(IndexError, setitem, sys.maxsize, b"a")
self.assertRaises(IndexError, setitem, -sys.maxsize, b"a")
# Wrong index/slice types
self.assertRaises(TypeError, setitem, 0.0, b"a")
self.assertRaises(TypeError, setitem, (0,), b"a")
self.assertRaises(TypeError, setitem, "a", b"a")
# Trying to resize the memory object
self.assertRaises(ValueError, setitem, 0, b"")
self.assertRaises(ValueError, setitem, 0, b"ab")
self.assertRaises(ValueError, setitem, slice(1,1), b"a")
self.assertRaises(ValueError, setitem, slice(0,2), b"a")
m = None
self.assertEqual(sys.getrefcount(b), oldrefcount)
def test_delitem(self):
for tp in self._types:
b = tp(self._source)
m = self._view(b)
with self.assertRaises(TypeError):
del m[1]
with self.assertRaises(TypeError):
del m[1:4]
def test_tobytes(self):
for tp in self._types:
m = self._view(tp(self._source))
b = m.tobytes()
# This calls self.getitem_type() on each separate byte of b"abcdef"
expected = b"".join(
self.getitem_type(c) for c in b"abcdef")
self.assertEqual(b, expected)
self.assertIsInstance(b, bytes)
def test_tolist(self):
for tp in self._types:
m = self._view(tp(self._source))
l = m.tolist()
self.assertEqual(l, map(ord, b"abcdef"))
def test_compare(self):
# memoryviews can compare for equality with other objects
# having the buffer interface.
for tp in self._types:
m = self._view(tp(self._source))
for tp_comp in self._types:
self.assertTrue(m == tp_comp(b"abcdef"))
self.assertFalse(m != tp_comp(b"abcdef"))
self.assertFalse(m == tp_comp(b"abcde"))
self.assertTrue(m != tp_comp(b"abcde"))
self.assertFalse(m == tp_comp(b"abcde1"))
self.assertTrue(m != tp_comp(b"abcde1"))
self.assertTrue(m == m)
self.assertTrue(m == m[:])
self.assertTrue(m[0:6] == m[:])
self.assertFalse(m[0:5] == m)
# Comparison with objects which don't support the buffer API
self.assertFalse(m == u"abcdef")
self.assertTrue(m != u"abcdef")
self.assertFalse(u"abcdef" == m)
self.assertTrue(u"abcdef" != m)
# Unordered comparisons are unimplemented, and therefore give
# arbitrary results (they raise a TypeError in py3k)
def check_attributes_with_type(self, tp):
m = self._view(tp(self._source))
self.assertEqual(m.format, self.format)
self.assertIsInstance(m.format, str)
self.assertEqual(m.itemsize, self.itemsize)
self.assertEqual(m.ndim, 1)
self.assertEqual(m.shape, (6,))
self.assertEqual(len(m), 6)
self.assertEqual(m.strides, (self.itemsize,))
self.assertEqual(m.suboffsets, None)
return m
def test_attributes_readonly(self):
if not self.ro_type:
self.skipTest("no read-only type to test")
m = self.check_attributes_with_type(self.ro_type)
self.assertEqual(m.readonly, True)
def test_attributes_writable(self):
if not self.rw_type:
self.skipTest("no writable type to test")
m = self.check_attributes_with_type(self.rw_type)
self.assertEqual(m.readonly, False)
# Disabled: unicode uses the old buffer API in 2.x
#def test_getbuffer(self):
## Test PyObject_GetBuffer() on a memoryview object.
#for tp in self._types:
#b = tp(self._source)
#oldrefcount = sys.getrefcount(b)
#m = self._view(b)
#oldviewrefcount = sys.getrefcount(m)
#s = unicode(m, "utf-8")
#self._check_contents(tp, b, s.encode("utf-8"))
#self.assertEqual(sys.getrefcount(m), oldviewrefcount)
#m = None
#self.assertEqual(sys.getrefcount(b), oldrefcount)
def test_gc(self):
for tp in self._types:
if not isinstance(tp, type):
# If tp is a factory rather than a plain type, skip
continue
class MySource(tp):
pass
class MyObject:
pass
# Create a reference cycle through a memoryview object
b = MySource(tp(b'abc'))
m = self._view(b)
o = MyObject()
b.m = m
b.o = o
wr = weakref.ref(o)
b = m = o = None
# The cycle must be broken
gc.collect()
self.assertTrue(wr() is None, wr())
def test_writable_readonly(self):
# Issue #10451: memoryview incorrectly exposes a readonly
# buffer as writable causing a segfault if using mmap
tp = self.ro_type
if tp is None:
self.skipTest("no read-only type to test")
b = tp(self._source)
m = self._view(b)
i = io.BytesIO(b'ZZZZ')
self.assertRaises(TypeError, i.readinto, m)
# Variations on source objects for the buffer: bytes-like objects, then arrays
# with itemsize > 1.
# NOTE: support for multi-dimensional objects is unimplemented.
class BaseBytesMemoryTests(AbstractMemoryTests):
ro_type = bytes
rw_type = bytearray
getitem_type = bytes
itemsize = 1
format = 'B'
# Disabled: array.array() does not support the new buffer API in 2.x
#class BaseArrayMemoryTests(AbstractMemoryTests):
#ro_type = None
#rw_type = lambda self, b: array.array('i', map(ord, b))
#getitem_type = lambda self, b: array.array('i', map(ord, b)).tostring()
#itemsize = array.array('i').itemsize
#format = 'i'
#def test_getbuffer(self):
## XXX Test should be adapted for non-byte buffers
#pass
#def test_tolist(self):
## XXX NotImplementedError: tolist() only supports byte views
#pass
# Variations on indirection levels: memoryview, slice of memoryview,
# slice of slice of memoryview.
# This is important to test allocation subtleties.
class BaseMemoryviewTests:
def _view(self, obj):
return memoryview(obj)
def _check_contents(self, tp, obj, contents):
self.assertEqual(obj, tp(contents))
class BaseMemorySliceTests:
source_bytes = b"XabcdefY"
def _view(self, obj):
m = memoryview(obj)
return m[1:7]
def _check_contents(self, tp, obj, contents):
self.assertEqual(obj[1:7], tp(contents))
def test_refs(self):
for tp in self._types:
m = memoryview(tp(self._source))
oldrefcount = sys.getrefcount(m)
m[1:2]
self.assertEqual(sys.getrefcount(m), oldrefcount)
class BaseMemorySliceSliceTests:
source_bytes = b"XabcdefY"
def _view(self, obj):
m = memoryview(obj)
return m[:7][1:]
def _check_contents(self, tp, obj, contents):
self.assertEqual(obj[1:7], tp(contents))
# Concrete test classes
class BytesMemoryviewTest(unittest.TestCase,
BaseMemoryviewTests, BaseBytesMemoryTests):
def test_constructor(self):
for tp in self._types:
ob = tp(self._source)
self.assertTrue(memoryview(ob))
self.assertTrue(memoryview(object=ob))
self.assertRaises(TypeError, memoryview)
self.assertRaises(TypeError, memoryview, ob, ob)
self.assertRaises(TypeError, memoryview, argument=ob)
self.assertRaises(TypeError, memoryview, ob, argument=True)
#class ArrayMemoryviewTest(unittest.TestCase,
#BaseMemoryviewTests, BaseArrayMemoryTests):
#def test_array_assign(self):
## Issue #4569: segfault when mutating a memoryview with itemsize != 1
#a = array.array('i', range(10))
#m = memoryview(a)
#new_a = array.array('i', range(9, -1, -1))
#m[:] = new_a
#self.assertEqual(a, new_a)
class BytesMemorySliceTest(unittest.TestCase,
BaseMemorySliceTests, BaseBytesMemoryTests):
pass
#class ArrayMemorySliceTest(unittest.TestCase,
#BaseMemorySliceTests, BaseArrayMemoryTests):
#pass
class BytesMemorySliceSliceTest(unittest.TestCase,
BaseMemorySliceSliceTests, BaseBytesMemoryTests):
pass
#class ArrayMemorySliceSliceTest(unittest.TestCase,
#BaseMemorySliceSliceTests, BaseArrayMemoryTests):
#pass
class OtherTest(unittest.TestCase):
def test_copy(self):
m = memoryview(b'abc')
with self.assertRaises(TypeError):
copy.copy(m)
# See issue #22995
## def test_pickle(self):
## m = memoryview(b'abc')
## for proto in range(pickle.HIGHEST_PROTOCOL + 1):
## with self.assertRaises(TypeError):
## pickle.dumps(m, proto)
def test_main():
test_support.run_unittest(__name__)
if __name__ == "__main__":
test_main()