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      1 doctests = """
      2 ########### Tests mostly copied from test_listcomps.py ############
      3 
      4 Test simple loop with conditional
      5 
      6     >>> sum({i*i for i in range(100) if i&1 == 1})
      7     166650
      8 
      9 Test simple case
     10 
     11     >>> {2*y + x + 1 for x in (0,) for y in (1,)}
     12     set([3])
     13 
     14 Test 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 
     19 Test 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 
     24 Make 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 
     33 Verify 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 
     46 Make 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 
     53 Same 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 
     59 Generators 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 
     68 Make 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 
     75 Return 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 
     81 Same 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 
     87 Another 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 
     94 And 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 
    101 We 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 
    134 def 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 
    150 if __name__ == "__main__":
    151     test_main(verbose=True)
    152