Mini Shell
"""Unit tests for the PickleBuffer object.
Pickling tests themselves are in pickletester.py.
"""
import gc
from pickle import PickleBuffer
import weakref
import unittest
from test import support
class B(bytes):
pass
class PickleBufferTest(unittest.TestCase):
def check_memoryview(self, pb, equiv):
with memoryview(pb) as m:
with memoryview(equiv) as expected:
self.assertEqual(m.nbytes, expected.nbytes)
self.assertEqual(m.readonly, expected.readonly)
self.assertEqual(m.itemsize, expected.itemsize)
self.assertEqual(m.shape, expected.shape)
self.assertEqual(m.strides, expected.strides)
self.assertEqual(m.c_contiguous, expected.c_contiguous)
self.assertEqual(m.f_contiguous, expected.f_contiguous)
self.assertEqual(m.format, expected.format)
self.assertEqual(m.tobytes(), expected.tobytes())
def test_constructor_failure(self):
with self.assertRaises(TypeError):
PickleBuffer()
with self.assertRaises(TypeError):
PickleBuffer("foo")
# Released memoryview fails taking a buffer
m = memoryview(b"foo")
m.release()
with self.assertRaises(ValueError):
PickleBuffer(m)
def test_basics(self):
pb = PickleBuffer(b"foo")
self.assertEqual(b"foo", bytes(pb))
with memoryview(pb) as m:
self.assertTrue(m.readonly)
pb = PickleBuffer(bytearray(b"foo"))
self.assertEqual(b"foo", bytes(pb))
with memoryview(pb) as m:
self.assertFalse(m.readonly)
m[0] = 48
self.assertEqual(b"0oo", bytes(pb))
def test_release(self):
pb = PickleBuffer(b"foo")
pb.release()
with self.assertRaises(ValueError) as raises:
memoryview(pb)
self.assertIn("operation forbidden on released PickleBuffer object",
str(raises.exception))
# Idempotency
pb.release()
def test_cycle(self):
b = B(b"foo")
pb = PickleBuffer(b)
b.cycle = pb
wpb = weakref.ref(pb)
del b, pb
gc.collect()
self.assertIsNone(wpb())
def test_ndarray_2d(self):
# C-contiguous
ndarray = support.import_module("_testbuffer").ndarray
arr = ndarray(list(range(12)), shape=(4, 3), format='<i')
self.assertTrue(arr.c_contiguous)
self.assertFalse(arr.f_contiguous)
pb = PickleBuffer(arr)
self.check_memoryview(pb, arr)
# Non-contiguous
arr = arr[::2]
self.assertFalse(arr.c_contiguous)
self.assertFalse(arr.f_contiguous)
pb = PickleBuffer(arr)
self.check_memoryview(pb, arr)
# F-contiguous
arr = ndarray(list(range(12)), shape=(3, 4), strides=(4, 12), format='<i')
self.assertTrue(arr.f_contiguous)
self.assertFalse(arr.c_contiguous)
pb = PickleBuffer(arr)
self.check_memoryview(pb, arr)
# Tests for PickleBuffer.raw()
def check_raw(self, obj, equiv):
pb = PickleBuffer(obj)
with pb.raw() as m:
self.assertIsInstance(m, memoryview)
self.check_memoryview(m, equiv)
def test_raw(self):
for obj in (b"foo", bytearray(b"foo")):
with self.subTest(obj=obj):
self.check_raw(obj, obj)
def test_raw_ndarray(self):
# 1-D, contiguous
ndarray = support.import_module("_testbuffer").ndarray
arr = ndarray(list(range(3)), shape=(3,), format='<h')
equiv = b"\x00\x00\x01\x00\x02\x00"
self.check_raw(arr, equiv)
# 2-D, C-contiguous
arr = ndarray(list(range(6)), shape=(2, 3), format='<h')
equiv = b"\x00\x00\x01\x00\x02\x00\x03\x00\x04\x00\x05\x00"
self.check_raw(arr, equiv)
# 2-D, F-contiguous
arr = ndarray(list(range(6)), shape=(2, 3), strides=(2, 4),
format='<h')
# Note this is different from arr.tobytes()
equiv = b"\x00\x00\x01\x00\x02\x00\x03\x00\x04\x00\x05\x00"
self.check_raw(arr, equiv)
# 0-D
arr = ndarray(456, shape=(), format='<i')
equiv = b'\xc8\x01\x00\x00'
self.check_raw(arr, equiv)
def check_raw_non_contiguous(self, obj):
pb = PickleBuffer(obj)
with self.assertRaisesRegex(BufferError, "non-contiguous"):
pb.raw()
def test_raw_non_contiguous(self):
# 1-D
ndarray = support.import_module("_testbuffer").ndarray
arr = ndarray(list(range(6)), shape=(6,), format='<i')[::2]
self.check_raw_non_contiguous(arr)
# 2-D
arr = ndarray(list(range(12)), shape=(4, 3), format='<i')[::2]
self.check_raw_non_contiguous(arr)
def test_raw_released(self):
pb = PickleBuffer(b"foo")
pb.release()
with self.assertRaises(ValueError) as raises:
pb.raw()
if __name__ == "__main__":
unittest.main()
Zerion Mini Shell 1.0