1 from ctypes import * 2 import unittest 3 4 class VarSizeTest(unittest.TestCase): 5 def test_resize(self): 6 class X(Structure): 7 _fields_ = [("item", c_int), 8 ("array", c_int * 1)] 9 10 self.assertEqual(sizeof(X), sizeof(c_int) * 2) 11 x = X() 12 x.item = 42 13 x.array[0] = 100 14 self.assertEqual(sizeof(x), sizeof(c_int) * 2) 15 16 # make room for one additional item 17 new_size = sizeof(X) + sizeof(c_int) * 1 18 resize(x, new_size) 19 self.assertEqual(sizeof(x), new_size) 20 self.assertEqual((x.item, x.array[0]), (42, 100)) 21 22 # make room for 10 additional items 23 new_size = sizeof(X) + sizeof(c_int) * 9 24 resize(x, new_size) 25 self.assertEqual(sizeof(x), new_size) 26 self.assertEqual((x.item, x.array[0]), (42, 100)) 27 28 # make room for one additional item 29 new_size = sizeof(X) + sizeof(c_int) * 1 30 resize(x, new_size) 31 self.assertEqual(sizeof(x), new_size) 32 self.assertEqual((x.item, x.array[0]), (42, 100)) 33 34 def test_array_invalid_length(self): 35 # cannot create arrays with non-positive size 36 self.assertRaises(ValueError, lambda: c_int * -1) 37 self.assertRaises(ValueError, lambda: c_int * -3) 38 39 def test_zerosized_array(self): 40 array = (c_int * 0)() 41 # accessing elements of zero-sized arrays raise IndexError 42 self.assertRaises(IndexError, array.__setitem__, 0, None) 43 self.assertRaises(IndexError, array.__getitem__, 0) 44 self.assertRaises(IndexError, array.__setitem__, 1, None) 45 self.assertRaises(IndexError, array.__getitem__, 1) 46 self.assertRaises(IndexError, array.__setitem__, -1, None) 47 self.assertRaises(IndexError, array.__getitem__, -1) 48 49 if __name__ == "__main__": 50 unittest.main() 51
