1 import unittest 2 3 # For scope testing. 4 g = "Global variable" 5 6 7 class DictComprehensionTest(unittest.TestCase): 8 9 def test_basics(self): 10 expected = {0: 10, 1: 11, 2: 12, 3: 13, 4: 14, 5: 15, 6: 16, 7: 17, 11 8: 18, 9: 19} 12 actual = {k: k + 10 for k in range(10)} 13 self.assertEqual(actual, expected) 14 15 expected = {0: 0, 1: 1, 2: 2, 3: 3, 4: 4, 5: 5, 6: 6, 7: 7, 8: 8, 9: 9} 16 actual = {k: v for k in range(10) for v in range(10) if k == v} 17 self.assertEqual(actual, expected) 18 19 def test_scope_isolation(self): 20 k = "Local Variable" 21 22 expected = {0: None, 1: None, 2: None, 3: None, 4: None, 5: None, 23 6: None, 7: None, 8: None, 9: None} 24 actual = {k: None for k in range(10)} 25 self.assertEqual(actual, expected) 26 self.assertEqual(k, "Local Variable") 27 28 expected = {9: 1, 18: 2, 19: 2, 27: 3, 28: 3, 29: 3, 36: 4, 37: 4, 29 38: 4, 39: 4, 45: 5, 46: 5, 47: 5, 48: 5, 49: 5, 54: 6, 30 55: 6, 56: 6, 57: 6, 58: 6, 59: 6, 63: 7, 64: 7, 65: 7, 31 66: 7, 67: 7, 68: 7, 69: 7, 72: 8, 73: 8, 74: 8, 75: 8, 32 76: 8, 77: 8, 78: 8, 79: 8, 81: 9, 82: 9, 83: 9, 84: 9, 33 85: 9, 86: 9, 87: 9, 88: 9, 89: 9} 34 actual = {k: v for v in range(10) for k in range(v * 9, v * 10)} 35 self.assertEqual(k, "Local Variable") 36 self.assertEqual(actual, expected) 37 38 def test_scope_isolation_from_global(self): 39 expected = {0: None, 1: None, 2: None, 3: None, 4: None, 5: None, 40 6: None, 7: None, 8: None, 9: None} 41 actual = {g: None for g in range(10)} 42 self.assertEqual(actual, expected) 43 self.assertEqual(g, "Global variable") 44 45 expected = {9: 1, 18: 2, 19: 2, 27: 3, 28: 3, 29: 3, 36: 4, 37: 4, 46 38: 4, 39: 4, 45: 5, 46: 5, 47: 5, 48: 5, 49: 5, 54: 6, 47 55: 6, 56: 6, 57: 6, 58: 6, 59: 6, 63: 7, 64: 7, 65: 7, 48 66: 7, 67: 7, 68: 7, 69: 7, 72: 8, 73: 8, 74: 8, 75: 8, 49 76: 8, 77: 8, 78: 8, 79: 8, 81: 9, 82: 9, 83: 9, 84: 9, 50 85: 9, 86: 9, 87: 9, 88: 9, 89: 9} 51 actual = {g: v for v in range(10) for g in range(v * 9, v * 10)} 52 self.assertEqual(g, "Global variable") 53 self.assertEqual(actual, expected) 54 55 def test_global_visibility(self): 56 expected = {0: 'Global variable', 1: 'Global variable', 57 2: 'Global variable', 3: 'Global variable', 58 4: 'Global variable', 5: 'Global variable', 59 6: 'Global variable', 7: 'Global variable', 60 8: 'Global variable', 9: 'Global variable'} 61 actual = {k: g for k in range(10)} 62 self.assertEqual(actual, expected) 63 64 def test_local_visibility(self): 65 v = "Local variable" 66 expected = {0: 'Local variable', 1: 'Local variable', 67 2: 'Local variable', 3: 'Local variable', 68 4: 'Local variable', 5: 'Local variable', 69 6: 'Local variable', 7: 'Local variable', 70 8: 'Local variable', 9: 'Local variable'} 71 actual = {k: v for k in range(10)} 72 self.assertEqual(actual, expected) 73 self.assertEqual(v, "Local variable") 74 75 def test_illegal_assignment(self): 76 with self.assertRaisesRegex(SyntaxError, "can't assign"): 77 compile("{x: y for y, x in ((1, 2), (3, 4))} = 5", "<test>", 78 "exec") 79 80 with self.assertRaisesRegex(SyntaxError, "can't assign"): 81 compile("{x: y for y, x in ((1, 2), (3, 4))} += 5", "<test>", 82 "exec") 83 84 85 if __name__ == "__main__": 86 unittest.main() 87
