1 import unittest
2
3 # For scope testing.
4 g = "Global variable"
5
6
7 class ESC[4;38;5;81mDictComprehensionTest(ESC[4;38;5;149munittestESC[4;38;5;149m.ESC[4;38;5;149mTestCase):
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, "cannot assign"):
77 compile("{x: y for y, x in ((1, 2), (3, 4))} = 5", "<test>",
78 "exec")
79
80 with self.assertRaisesRegex(SyntaxError, "illegal expression"):
81 compile("{x: y for y, x in ((1, 2), (3, 4))} += 5", "<test>",
82 "exec")
83
84 def test_evaluation_order(self):
85 expected = {
86 'H': 'W',
87 'e': 'o',
88 'l': 'l',
89 'o': 'd',
90 }
91
92 expected_calls = [
93 ('key', 'H'), ('value', 'W'),
94 ('key', 'e'), ('value', 'o'),
95 ('key', 'l'), ('value', 'r'),
96 ('key', 'l'), ('value', 'l'),
97 ('key', 'o'), ('value', 'd'),
98 ]
99
100 actual_calls = []
101
102 def add_call(pos, value):
103 actual_calls.append((pos, value))
104 return value
105
106 actual = {
107 add_call('key', k): add_call('value', v)
108 for k, v in zip('Hello', 'World')
109 }
110
111 self.assertEqual(actual, expected)
112 self.assertEqual(actual_calls, expected_calls)
113
114 def test_assignment_idiom_in_comprehensions(self):
115 expected = {1: 1, 2: 4, 3: 9, 4: 16}
116 actual = {j: j*j for i in range(4) for j in [i+1]}
117 self.assertEqual(actual, expected)
118 expected = {3: 2, 5: 6, 7: 12, 9: 20}
119 actual = {j+k: j*k for i in range(4) for j in [i+1] for k in [j+1]}
120 self.assertEqual(actual, expected)
121 expected = {3: 2, 5: 6, 7: 12, 9: 20}
122 actual = {j+k: j*k for i in range(4) for j, k in [(i+1, i+2)]}
123 self.assertEqual(actual, expected)
124
125 def test_star_expression(self):
126 expected = {0: 0, 1: 1, 2: 4, 3: 9}
127 self.assertEqual({i: i*i for i in [*range(4)]}, expected)
128 self.assertEqual({i: i*i for i in (*range(4),)}, expected)
129
130
131 if __name__ == "__main__":
132 unittest.main()