1doctests = """
2########### Tests mostly copied from test_listcomps.py ############
3
4Test simple loop with conditional
5
6    >>> sum({i*i for i in range(100) if i&1 == 1})
7    166650
8
9Test simple case
10
11    >>> {2*y + x + 1 for x in (0,) for y in (1,)}
12    set([3])
13
14Test simple nesting
15
16    >>> list(sorted({(i,j) for i in range(3) for j in range(4)}))
17    [(0, 0), (0, 1), (0, 2), (0, 3), (1, 0), (1, 1), (1, 2), (1, 3), (2, 0), (2, 1), (2, 2), (2, 3)]
18
19Test nesting with the inner expression dependent on the outer
20
21    >>> list(sorted({(i,j) for i in range(4) for j in range(i)}))
22    [(1, 0), (2, 0), (2, 1), (3, 0), (3, 1), (3, 2)]
23
24Make sure the induction variable is not exposed
25
26    >>> i = 20
27    >>> sum({i*i for i in range(100)})
28    328350
29
30    >>> i
31    20
32
33Verify that syntax error's are raised for setcomps used as lvalues
34
35    >>> {y for y in (1,2)} = 10          # doctest: +IGNORE_EXCEPTION_DETAIL
36    Traceback (most recent call last):
37       ...
38    SyntaxError: ...
39
40    >>> {y for y in (1,2)} += 10         # doctest: +IGNORE_EXCEPTION_DETAIL
41    Traceback (most recent call last):
42       ...
43    SyntaxError: ...
44
45
46Make a nested set comprehension that acts like set(range())
47
48    >>> def srange(n):
49    ...     return {i for i in range(n)}
50    >>> list(sorted(srange(10)))
51    [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
52
53Same again, only as a lambda expression instead of a function definition
54
55    >>> lrange = lambda n:  {i for i in range(n)}
56    >>> list(sorted(lrange(10)))
57    [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
58
59Generators can call other generators:
60
61    >>> def grange(n):
62    ...     for x in {i for i in range(n)}:
63    ...         yield x
64    >>> list(sorted(grange(5)))
65    [0, 1, 2, 3, 4]
66
67
68Make sure that None is a valid return value
69
70    >>> {None for i in range(10)}
71    set([None])
72
73########### Tests for various scoping corner cases ############
74
75Return lambdas that use the iteration variable as a default argument
76
77    >>> items = {(lambda i=i: i) for i in range(5)}
78    >>> {x() for x in items} == set(range(5))
79    True
80
81Same again, only this time as a closure variable
82
83    >>> items = {(lambda: i) for i in range(5)}
84    >>> {x() for x in items}
85    set([4])
86
87Another way to test that the iteration variable is local to the list comp
88
89    >>> items = {(lambda: i) for i in range(5)}
90    >>> i = 20
91    >>> {x() for x in items}
92    set([4])
93
94And confirm that a closure can jump over the list comp scope
95
96    >>> items = {(lambda: y) for i in range(5)}
97    >>> y = 2
98    >>> {x() for x in items}
99    set([2])
100
101We also repeat each of the above scoping tests inside a function
102
103    >>> def test_func():
104    ...     items = {(lambda i=i: i) for i in range(5)}
105    ...     return {x() for x in items}
106    >>> test_func() == set(range(5))
107    True
108
109    >>> def test_func():
110    ...     items = {(lambda: i) for i in range(5)}
111    ...     return {x() for x in items}
112    >>> test_func()
113    set([4])
114
115    >>> def test_func():
116    ...     items = {(lambda: i) for i in range(5)}
117    ...     i = 20
118    ...     return {x() for x in items}
119    >>> test_func()
120    set([4])
121
122    >>> def test_func():
123    ...     items = {(lambda: y) for i in range(5)}
124    ...     y = 2
125    ...     return {x() for x in items}
126    >>> test_func()
127    set([2])
128
129"""
130
131
132__test__ = {'doctests' : doctests}
133
134def test_main(verbose=None):
135    import sys
136    from test import test_support
137    from test import test_setcomps
138    test_support.run_doctest(test_setcomps, verbose)
139
140    # verify reference counting
141    if verbose and hasattr(sys, "gettotalrefcount"):
142        import gc
143        counts = [None] * 5
144        for i in range(len(counts)):
145            test_support.run_doctest(test_setcomps, verbose)
146            gc.collect()
147            counts[i] = sys.gettotalrefcount()
148        print(counts)
149
150if __name__ == "__main__":
151    test_main(verbose=True)
152