from ctypes import *
import array
import gc
import unittest
class X(Structure):
_fields_ = [("c_int", c_int)]
init_called = False
def __init__(self):
self._init_called = True
class Test(unittest.TestCase):
def test_fom_buffer(self):
a = array.array("i", range(16))
x = (c_int * 16).from_buffer(a)
y = X.from_buffer(a)
self.assertEqual(y.c_int, a[0])
self.assertFalse(y.init_called)
self.assertEqual(x[:], a.tolist())
a[0], a[-1] = 200, -200
self.assertEqual(x[:], a.tolist())
self.assertIn(a, x._objects.values())
self.assertRaises(ValueError,
c_int.from_buffer, a, -1)
expected = x[:]
del a; gc.collect(); gc.collect(); gc.collect()
self.assertEqual(x[:], expected)
self.assertRaises(TypeError,
(c_char * 16).from_buffer, "a" * 16)
def test_fom_buffer_with_offset(self):
a = array.array("i", range(16))
x = (c_int * 15).from_buffer(a, sizeof(c_int))
self.assertEqual(x[:], a.tolist()[1:])
self.assertRaises(ValueError, lambda: (c_int * 16).from_buffer(a, sizeof(c_int)))
self.assertRaises(ValueError, lambda: (c_int * 1).from_buffer(a, 16 * sizeof(c_int)))
def test_from_buffer_copy(self):
a = array.array("i", range(16))
x = (c_int * 16).from_buffer_copy(a)
y = X.from_buffer_copy(a)
self.assertEqual(y.c_int, a[0])
self.assertFalse(y.init_called)
self.assertEqual(x[:], range(16))
a[0], a[-1] = 200, -200
self.assertEqual(x[:], range(16))
self.assertEqual(x._objects, None)
self.assertRaises(ValueError,
c_int.from_buffer, a, -1)
del a; gc.collect(); gc.collect(); gc.collect()
self.assertEqual(x[:], range(16))
x = (c_char * 16).from_buffer_copy("a" * 16)
self.assertEqual(x[:], "a" * 16)
def test_fom_buffer_copy_with_offset(self):
a = array.array("i", range(16))
x = (c_int * 15).from_buffer_copy(a, sizeof(c_int))
self.assertEqual(x[:], a.tolist()[1:])
self.assertRaises(ValueError,
(c_int * 16).from_buffer_copy, a, sizeof(c_int))
self.assertRaises(ValueError,
(c_int * 1).from_buffer_copy, a, 16 * sizeof(c_int))
def test_abstract(self):
from ctypes import _Pointer, _SimpleCData, _CFuncPtr
self.assertRaises(TypeError, Array.from_buffer, bytearray(10))
self.assertRaises(TypeError, Structure.from_buffer, bytearray(10))
self.assertRaises(TypeError, Union.from_buffer, bytearray(10))
self.assertRaises(TypeError, _CFuncPtr.from_buffer, bytearray(10))
self.assertRaises(TypeError, _Pointer.from_buffer, bytearray(10))
self.assertRaises(TypeError, _SimpleCData.from_buffer, bytearray(10))
self.assertRaises(TypeError, Array.from_buffer_copy, b"123")
self.assertRaises(TypeError, Structure.from_buffer_copy, b"123")
self.assertRaises(TypeError, Union.from_buffer_copy, b"123")
self.assertRaises(TypeError, _CFuncPtr.from_buffer_copy, b"123")
self.assertRaises(TypeError, _Pointer.from_buffer_copy, b"123")
self.assertRaises(TypeError, _SimpleCData.from_buffer_copy, b"123")
if __name__ == '__main__':
unittest.main()
