"""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()