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diff --git a/lib/python2.7/test/test_genexps.py b/lib/python2.7/test/test_genexps.py
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+doctests = """
+
+Test simple loop with conditional
+
+ >>> sum(i*i for i in range(100) if i&1 == 1)
+ 166650
+
+Test simple nesting
+
+ >>> list((i,j) for i in range(3) for j in range(4) )
+ [(0, 0), (0, 1), (0, 2), (0, 3), (1, 0), (1, 1), (1, 2), (1, 3), (2, 0), (2, 1), (2, 2), (2, 3)]
+
+Test nesting with the inner expression dependent on the outer
+
+ >>> list((i,j) for i in range(4) for j in range(i) )
+ [(1, 0), (2, 0), (2, 1), (3, 0), (3, 1), (3, 2)]
+
+Make sure the induction variable is not exposed
+
+ >>> i = 20
+ >>> sum(i*i for i in range(100))
+ 328350
+ >>> i
+ 20
+
+Test first class
+
+ >>> g = (i*i for i in range(4))
+ >>> type(g)
+ <type 'generator'>
+ >>> list(g)
+ [0, 1, 4, 9]
+
+Test direct calls to next()
+
+ >>> g = (i*i for i in range(3))
+ >>> g.next()
+ 0
+ >>> g.next()
+ 1
+ >>> g.next()
+ 4
+ >>> g.next()
+ Traceback (most recent call last):
+ File "<pyshell#21>", line 1, in -toplevel-
+ g.next()
+ StopIteration
+
+Does it stay stopped?
+
+ >>> g.next()
+ Traceback (most recent call last):
+ File "<pyshell#21>", line 1, in -toplevel-
+ g.next()
+ StopIteration
+ >>> list(g)
+ []
+
+Test running gen when defining function is out of scope
+
+ >>> def f(n):
+ ... return (i*i for i in xrange(n))
+ >>> list(f(10))
+ [0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
+
+ >>> def f(n):
+ ... return ((i,j) for i in xrange(3) for j in xrange(n))
+ >>> list(f(4))
+ [(0, 0), (0, 1), (0, 2), (0, 3), (1, 0), (1, 1), (1, 2), (1, 3), (2, 0), (2, 1), (2, 2), (2, 3)]
+ >>> def f(n):
+ ... return ((i,j) for i in xrange(3) for j in xrange(4) if j in xrange(n))
+ >>> list(f(4))
+ [(0, 0), (0, 1), (0, 2), (0, 3), (1, 0), (1, 1), (1, 2), (1, 3), (2, 0), (2, 1), (2, 2), (2, 3)]
+ >>> list(f(2))
+ [(0, 0), (0, 1), (1, 0), (1, 1), (2, 0), (2, 1)]
+
+Verify that parenthesis are required in a statement
+
+ >>> def f(n):
+ ... return i*i for i in xrange(n)
+ Traceback (most recent call last):
+ ...
+ SyntaxError: invalid syntax
+
+Verify that parenthesis are required when used as a keyword argument value
+
+ >>> dict(a = i for i in xrange(10))
+ Traceback (most recent call last):
+ ...
+ SyntaxError: invalid syntax
+
+Verify that parenthesis are required when used as a keyword argument value
+
+ >>> dict(a = (i for i in xrange(10))) #doctest: +ELLIPSIS
+ {'a': <generator object <genexpr> at ...>}
+
+Verify early binding for the outermost for-expression
+
+ >>> x=10
+ >>> g = (i*i for i in range(x))
+ >>> x = 5
+ >>> list(g)
+ [0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
+
+Verify that the outermost for-expression makes an immediate check
+for iterability
+
+ >>> (i for i in 6)
+ Traceback (most recent call last):
+ File "<pyshell#4>", line 1, in -toplevel-
+ (i for i in 6)
+ TypeError: 'int' object is not iterable
+
+Verify late binding for the outermost if-expression
+
+ >>> include = (2,4,6,8)
+ >>> g = (i*i for i in range(10) if i in include)
+ >>> include = (1,3,5,7,9)
+ >>> list(g)
+ [1, 9, 25, 49, 81]
+
+Verify late binding for the innermost for-expression
+
+ >>> g = ((i,j) for i in range(3) for j in range(x))
+ >>> x = 4
+ >>> list(g)
+ [(0, 0), (0, 1), (0, 2), (0, 3), (1, 0), (1, 1), (1, 2), (1, 3), (2, 0), (2, 1), (2, 2), (2, 3)]
+
+Verify re-use of tuples (a side benefit of using genexps over listcomps)
+
+ >>> tupleids = map(id, ((i,i) for i in xrange(10)))
+ >>> int(max(tupleids) - min(tupleids))
+ 0
+
+Verify that syntax error's are raised for genexps used as lvalues
+
+ >>> (y for y in (1,2)) = 10
+ Traceback (most recent call last):
+ ...
+ File "<doctest test.test_genexps.__test__.doctests[40]>", line 1
+ SyntaxError: can't assign to generator expression
+
+ >>> (y for y in (1,2)) += 10
+ Traceback (most recent call last):
+ ...
+ File "<doctest test.test_genexps.__test__.doctests[41]>", line 1
+ SyntaxError: can't assign to generator expression
+
+
+########### Tests borrowed from or inspired by test_generators.py ############
+
+Make a generator that acts like range()
+
+ >>> yrange = lambda n: (i for i in xrange(n))
+ >>> list(yrange(10))
+ [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
+
+Generators always return to the most recent caller:
+
+ >>> def creator():
+ ... r = yrange(5)
+ ... print "creator", r.next()
+ ... return r
+ >>> def caller():
+ ... r = creator()
+ ... for i in r:
+ ... print "caller", i
+ >>> caller()
+ creator 0
+ caller 1
+ caller 2
+ caller 3
+ caller 4
+
+Generators can call other generators:
+
+ >>> def zrange(n):
+ ... for i in yrange(n):
+ ... yield i
+ >>> list(zrange(5))
+ [0, 1, 2, 3, 4]
+
+
+Verify that a gen exp cannot be resumed while it is actively running:
+
+ >>> g = (me.next() for i in xrange(10))
+ >>> me = g
+ >>> me.next()
+ Traceback (most recent call last):
+ File "<pyshell#30>", line 1, in -toplevel-
+ me.next()
+ File "<pyshell#28>", line 1, in <generator expression>
+ g = (me.next() for i in xrange(10))
+ ValueError: generator already executing
+
+Verify exception propagation
+
+ >>> g = (10 // i for i in (5, 0, 2))
+ >>> g.next()
+ 2
+ >>> g.next()
+ Traceback (most recent call last):
+ File "<pyshell#37>", line 1, in -toplevel-
+ g.next()
+ File "<pyshell#35>", line 1, in <generator expression>
+ g = (10 // i for i in (5, 0, 2))
+ ZeroDivisionError: integer division or modulo by zero
+ >>> g.next()
+ Traceback (most recent call last):
+ File "<pyshell#38>", line 1, in -toplevel-
+ g.next()
+ StopIteration
+
+Make sure that None is a valid return value
+
+ >>> list(None for i in xrange(10))
+ [None, None, None, None, None, None, None, None, None, None]
+
+Check that generator attributes are present
+
+ >>> g = (i*i for i in range(3))
+ >>> expected = set(['gi_frame', 'gi_running', 'next'])
+ >>> set(attr for attr in dir(g) if not attr.startswith('__')) >= expected
+ True
+
+ >>> from test.test_support import HAVE_DOCSTRINGS
+ >>> print(g.next.__doc__ if HAVE_DOCSTRINGS else 'x.next() -> the next value, or raise StopIteration')
+ x.next() -> the next value, or raise StopIteration
+ >>> import types
+ >>> isinstance(g, types.GeneratorType)
+ True
+
+Check the __iter__ slot is defined to return self
+
+ >>> iter(g) is g
+ True
+
+Verify that the running flag is set properly
+
+ >>> g = (me.gi_running for i in (0,1))
+ >>> me = g
+ >>> me.gi_running
+ 0
+ >>> me.next()
+ 1
+ >>> me.gi_running
+ 0
+
+Verify that genexps are weakly referencable
+
+ >>> import weakref
+ >>> g = (i*i for i in range(4))
+ >>> wr = weakref.ref(g)
+ >>> wr() is g
+ True
+ >>> p = weakref.proxy(g)
+ >>> list(p)
+ [0, 1, 4, 9]
+
+
+"""
+
+
+__test__ = {'doctests' : doctests}
+
+def test_main(verbose=None):
+ import sys
+ from test import test_support
+ from test import test_genexps
+ test_support.run_doctest(test_genexps, verbose)
+
+ # verify reference counting
+ if verbose and hasattr(sys, "gettotalrefcount"):
+ import gc
+ counts = [None] * 5
+ for i in xrange(len(counts)):
+ test_support.run_doctest(test_genexps, verbose)
+ gc.collect()
+ counts[i] = sys.gettotalrefcount()
+ print counts
+
+if __name__ == "__main__":
+ test_main(verbose=True)
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-06 21:10:34 +0000