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diff --git a/lib/python2.7/test/test_itertools.py b/lib/python2.7/test/test_itertools.py
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-import unittest
-from test import test_support
-from itertools import *
-from weakref import proxy
-from decimal import Decimal
-from fractions import Fraction
-import sys
-import operator
-import random
-import copy
-import pickle
-from functools import reduce
-maxsize = test_support.MAX_Py_ssize_t
-minsize = -maxsize-1
-
-def onearg(x):
- 'Test function of one argument'
- return 2*x
-
-def errfunc(*args):
- 'Test function that raises an error'
- raise ValueError
-
-def gen3():
- 'Non-restartable source sequence'
- for i in (0, 1, 2):
- yield i
-
-def isEven(x):
- 'Test predicate'
- return x%2==0
-
-def isOdd(x):
- 'Test predicate'
- return x%2==1
-
-class StopNow:
- 'Class emulating an empty iterable.'
- def __iter__(self):
- return self
- def next(self):
- raise StopIteration
-
-def take(n, seq):
- 'Convenience function for partially consuming a long of infinite iterable'
- return list(islice(seq, n))
-
-def prod(iterable):
- return reduce(operator.mul, iterable, 1)
-
-def fact(n):
- 'Factorial'
- return prod(range(1, n+1))
-
-class TestBasicOps(unittest.TestCase):
- def test_chain(self):
-
- def chain2(*iterables):
- 'Pure python version in the docs'
- for it in iterables:
- for element in it:
- yield element
-
- for c in (chain, chain2):
- self.assertEqual(list(c('abc', 'def')), list('abcdef'))
- self.assertEqual(list(c('abc')), list('abc'))
- self.assertEqual(list(c('')), [])
- self.assertEqual(take(4, c('abc', 'def')), list('abcd'))
- self.assertRaises(TypeError, list,c(2, 3))
-
- def test_chain_from_iterable(self):
- self.assertEqual(list(chain.from_iterable(['abc', 'def'])), list('abcdef'))
- self.assertEqual(list(chain.from_iterable(['abc'])), list('abc'))
- self.assertEqual(list(chain.from_iterable([''])), [])
- self.assertEqual(take(4, chain.from_iterable(['abc', 'def'])), list('abcd'))
- self.assertRaises(TypeError, list, chain.from_iterable([2, 3]))
-
- def test_combinations(self):
- self.assertRaises(TypeError, combinations, 'abc') # missing r argument
- self.assertRaises(TypeError, combinations, 'abc', 2, 1) # too many arguments
- self.assertRaises(TypeError, combinations, None) # pool is not iterable
- self.assertRaises(ValueError, combinations, 'abc', -2) # r is negative
- self.assertEqual(list(combinations('abc', 32)), []) # r > n
- self.assertEqual(list(combinations(range(4), 3)),
- [(0,1,2), (0,1,3), (0,2,3), (1,2,3)])
-
- def combinations1(iterable, r):
- 'Pure python version shown in the docs'
- pool = tuple(iterable)
- n = len(pool)
- if r > n:
- return
- indices = range(r)
- yield tuple(pool[i] for i in indices)
- while 1:
- for i in reversed(range(r)):
- if indices[i] != i + n - r:
- break
- else:
- return
- indices[i] += 1
- for j in range(i+1, r):
- indices[j] = indices[j-1] + 1
- yield tuple(pool[i] for i in indices)
-
- def combinations2(iterable, r):
- 'Pure python version shown in the docs'
- pool = tuple(iterable)
- n = len(pool)
- for indices in permutations(range(n), r):
- if sorted(indices) == list(indices):
- yield tuple(pool[i] for i in indices)
-
- def combinations3(iterable, r):
- 'Pure python version from cwr()'
- pool = tuple(iterable)
- n = len(pool)
- for indices in combinations_with_replacement(range(n), r):
- if len(set(indices)) == r:
- yield tuple(pool[i] for i in indices)
-
- for n in range(7):
- values = [5*x-12 for x in range(n)]
- for r in range(n+2):
- result = list(combinations(values, r))
- self.assertEqual(len(result), 0 if r>n else fact(n) // fact(r) // fact(n-r)) # right number of combs
- self.assertEqual(len(result), len(set(result))) # no repeats
- self.assertEqual(result, sorted(result)) # lexicographic order
- for c in result:
- self.assertEqual(len(c), r) # r-length combinations
- self.assertEqual(len(set(c)), r) # no duplicate elements
- self.assertEqual(list(c), sorted(c)) # keep original ordering
- self.assertTrue(all(e in values for e in c)) # elements taken from input iterable
- self.assertEqual(list(c),
- [e for e in values if e in c]) # comb is a subsequence of the input iterable
- self.assertEqual(result, list(combinations1(values, r))) # matches first pure python version
- self.assertEqual(result, list(combinations2(values, r))) # matches second pure python version
- self.assertEqual(result, list(combinations3(values, r))) # matches second pure python version
-
- @test_support.impl_detail("tuple reuse is specific to CPython")
- def test_combinations_tuple_reuse(self):
- self.assertEqual(len(set(map(id, combinations('abcde', 3)))), 1)
- self.assertNotEqual(len(set(map(id, list(combinations('abcde', 3))))), 1)
-
- def test_combinations_with_replacement(self):
- cwr = combinations_with_replacement
- self.assertRaises(TypeError, cwr, 'abc') # missing r argument
- self.assertRaises(TypeError, cwr, 'abc', 2, 1) # too many arguments
- self.assertRaises(TypeError, cwr, None) # pool is not iterable
- self.assertRaises(ValueError, cwr, 'abc', -2) # r is negative
- self.assertEqual(list(cwr('ABC', 2)),
- [('A','A'), ('A','B'), ('A','C'), ('B','B'), ('B','C'), ('C','C')])
-
- def cwr1(iterable, r):
- 'Pure python version shown in the docs'
- # number items returned: (n+r-1)! / r! / (n-1)! when n>0
- pool = tuple(iterable)
- n = len(pool)
- if not n and r:
- return
- indices = [0] * r
- yield tuple(pool[i] for i in indices)
- while 1:
- for i in reversed(range(r)):
- if indices[i] != n - 1:
- break
- else:
- return
- indices[i:] = [indices[i] + 1] * (r - i)
- yield tuple(pool[i] for i in indices)
-
- def cwr2(iterable, r):
- 'Pure python version shown in the docs'
- pool = tuple(iterable)
- n = len(pool)
- for indices in product(range(n), repeat=r):
- if sorted(indices) == list(indices):
- yield tuple(pool[i] for i in indices)
-
- def numcombs(n, r):
- if not n:
- return 0 if r else 1
- return fact(n+r-1) // fact(r) // fact(n-1)
-
- for n in range(7):
- values = [5*x-12 for x in range(n)]
- for r in range(n+2):
- result = list(cwr(values, r))
-
- self.assertEqual(len(result), numcombs(n, r)) # right number of combs
- self.assertEqual(len(result), len(set(result))) # no repeats
- self.assertEqual(result, sorted(result)) # lexicographic order
-
- regular_combs = list(combinations(values, r)) # compare to combs without replacement
- if n == 0 or r <= 1:
- self.assertEqual(result, regular_combs) # cases that should be identical
- else:
- self.assertTrue(set(result) >= set(regular_combs)) # rest should be supersets of regular combs
-
- for c in result:
- self.assertEqual(len(c), r) # r-length combinations
- noruns = [k for k,v in groupby(c)] # combo without consecutive repeats
- self.assertEqual(len(noruns), len(set(noruns))) # no repeats other than consecutive
- self.assertEqual(list(c), sorted(c)) # keep original ordering
- self.assertTrue(all(e in values for e in c)) # elements taken from input iterable
- self.assertEqual(noruns,
- [e for e in values if e in c]) # comb is a subsequence of the input iterable
- self.assertEqual(result, list(cwr1(values, r))) # matches first pure python version
- self.assertEqual(result, list(cwr2(values, r))) # matches second pure python version
-
- @test_support.impl_detail("tuple reuse is specific to CPython")
- def test_combinations_with_replacement_tuple_reuse(self):
- cwr = combinations_with_replacement
- self.assertEqual(len(set(map(id, cwr('abcde', 3)))), 1)
- self.assertNotEqual(len(set(map(id, list(cwr('abcde', 3))))), 1)
-
- def test_permutations(self):
- self.assertRaises(TypeError, permutations) # too few arguments
- self.assertRaises(TypeError, permutations, 'abc', 2, 1) # too many arguments
- self.assertRaises(TypeError, permutations, None) # pool is not iterable
- self.assertRaises(ValueError, permutations, 'abc', -2) # r is negative
- self.assertEqual(list(permutations('abc', 32)), []) # r > n
- self.assertRaises(TypeError, permutations, 'abc', 's') # r is not an int or None
- self.assertEqual(list(permutations(range(3), 2)),
- [(0,1), (0,2), (1,0), (1,2), (2,0), (2,1)])
-
- def permutations1(iterable, r=None):
- 'Pure python version shown in the docs'
- pool = tuple(iterable)
- n = len(pool)
- r = n if r is None else r
- if r > n:
- return
- indices = range(n)
- cycles = range(n, n-r, -1)
- yield tuple(pool[i] for i in indices[:r])
- while n:
- for i in reversed(range(r)):
- cycles[i] -= 1
- if cycles[i] == 0:
- indices[i:] = indices[i+1:] + indices[i:i+1]
- cycles[i] = n - i
- else:
- j = cycles[i]
- indices[i], indices[-j] = indices[-j], indices[i]
- yield tuple(pool[i] for i in indices[:r])
- break
- else:
- return
-
- def permutations2(iterable, r=None):
- 'Pure python version shown in the docs'
- pool = tuple(iterable)
- n = len(pool)
- r = n if r is None else r
- for indices in product(range(n), repeat=r):
- if len(set(indices)) == r:
- yield tuple(pool[i] for i in indices)
-
- for n in range(7):
- values = [5*x-12 for x in range(n)]
- for r in range(n+2):
- result = list(permutations(values, r))
- self.assertEqual(len(result), 0 if r>n else fact(n) // fact(n-r)) # right number of perms
- self.assertEqual(len(result), len(set(result))) # no repeats
- self.assertEqual(result, sorted(result)) # lexicographic order
- for p in result:
- self.assertEqual(len(p), r) # r-length permutations
- self.assertEqual(len(set(p)), r) # no duplicate elements
- self.assertTrue(all(e in values for e in p)) # elements taken from input iterable
- self.assertEqual(result, list(permutations1(values, r))) # matches first pure python version
- self.assertEqual(result, list(permutations2(values, r))) # matches second pure python version
- if r == n:
- self.assertEqual(result, list(permutations(values, None))) # test r as None
- self.assertEqual(result, list(permutations(values))) # test default r
-
- @test_support.impl_detail("tuple resuse is CPython specific")
- def test_permutations_tuple_reuse(self):
- self.assertEqual(len(set(map(id, permutations('abcde', 3)))), 1)
- self.assertNotEqual(len(set(map(id, list(permutations('abcde', 3))))), 1)
-
- def test_combinatorics(self):
- # Test relationships between product(), permutations(),
- # combinations() and combinations_with_replacement().
-
- for n in range(6):
- s = 'ABCDEFG'[:n]
- for r in range(8):
- prod = list(product(s, repeat=r))
- cwr = list(combinations_with_replacement(s, r))
- perm = list(permutations(s, r))
- comb = list(combinations(s, r))
-
- # Check size
- self.assertEqual(len(prod), n**r)
- self.assertEqual(len(cwr), (fact(n+r-1) // fact(r) // fact(n-1)) if n else (not r))
- self.assertEqual(len(perm), 0 if r>n else fact(n) // fact(n-r))
- self.assertEqual(len(comb), 0 if r>n else fact(n) // fact(r) // fact(n-r))
-
- # Check lexicographic order without repeated tuples
- self.assertEqual(prod, sorted(set(prod)))
- self.assertEqual(cwr, sorted(set(cwr)))
- self.assertEqual(perm, sorted(set(perm)))
- self.assertEqual(comb, sorted(set(comb)))
-
- # Check interrelationships
- self.assertEqual(cwr, [t for t in prod if sorted(t)==list(t)]) # cwr: prods which are sorted
- self.assertEqual(perm, [t for t in prod if len(set(t))==r]) # perm: prods with no dups
- self.assertEqual(comb, [t for t in perm if sorted(t)==list(t)]) # comb: perms that are sorted
- self.assertEqual(comb, [t for t in cwr if len(set(t))==r]) # comb: cwrs without dups
- self.assertEqual(comb, filter(set(cwr).__contains__, perm)) # comb: perm that is a cwr
- self.assertEqual(comb, filter(set(perm).__contains__, cwr)) # comb: cwr that is a perm
- self.assertEqual(comb, sorted(set(cwr) & set(perm))) # comb: both a cwr and a perm
-
- def test_compress(self):
- self.assertEqual(list(compress(data='ABCDEF', selectors=[1,0,1,0,1,1])), list('ACEF'))
- self.assertEqual(list(compress('ABCDEF', [1,0,1,0,1,1])), list('ACEF'))
- self.assertEqual(list(compress('ABCDEF', [0,0,0,0,0,0])), list(''))
- self.assertEqual(list(compress('ABCDEF', [1,1,1,1,1,1])), list('ABCDEF'))
- self.assertEqual(list(compress('ABCDEF', [1,0,1])), list('AC'))
- self.assertEqual(list(compress('ABC', [0,1,1,1,1,1])), list('BC'))
- n = 10000
- data = chain.from_iterable(repeat(range(6), n))
- selectors = chain.from_iterable(repeat((0, 1)))
- self.assertEqual(list(compress(data, selectors)), [1,3,5] * n)
- self.assertRaises(TypeError, compress, None, range(6)) # 1st arg not iterable
- self.assertRaises(TypeError, compress, range(6), None) # 2nd arg not iterable
- self.assertRaises(TypeError, compress, range(6)) # too few args
- self.assertRaises(TypeError, compress, range(6), None) # too many args
-
- def test_count(self):
- self.assertEqual(zip('abc',count()), [('a', 0), ('b', 1), ('c', 2)])
- self.assertEqual(zip('abc',count(3)), [('a', 3), ('b', 4), ('c', 5)])
- self.assertEqual(take(2, zip('abc',count(3))), [('a', 3), ('b', 4)])
- self.assertEqual(take(2, zip('abc',count(-1))), [('a', -1), ('b', 0)])
- self.assertEqual(take(2, zip('abc',count(-3))), [('a', -3), ('b', -2)])
- self.assertRaises(TypeError, count, 2, 3, 4)
- self.assertRaises(TypeError, count, 'a')
- self.assertEqual(list(islice(count(maxsize-5), 10)), range(maxsize-5, maxsize+5))
- self.assertEqual(list(islice(count(-maxsize-5), 10)), range(-maxsize-5, -maxsize+5))
- c = count(3)
- self.assertEqual(repr(c), 'count(3)')
- c.next()
- self.assertEqual(repr(c), 'count(4)')
- c = count(-9)
- self.assertEqual(repr(c), 'count(-9)')
- c.next()
- self.assertEqual(repr(count(10.25)), 'count(10.25)')
- self.assertEqual(c.next(), -8)
- for i in (-sys.maxint-5, -sys.maxint+5 ,-10, -1, 0, 10, sys.maxint-5, sys.maxint+5):
- # Test repr (ignoring the L in longs)
- r1 = repr(count(i)).replace('L', '')
- r2 = 'count(%r)'.__mod__(i).replace('L', '')
- self.assertEqual(r1, r2)
-
- # check copy, deepcopy, pickle
- for value in -3, 3, sys.maxint-5, sys.maxint+5:
- c = count(value)
- self.assertEqual(next(copy.copy(c)), value)
- self.assertEqual(next(copy.deepcopy(c)), value)
- self.assertEqual(next(pickle.loads(pickle.dumps(c))), value)
-
- def test_count_with_stride(self):
- self.assertEqual(zip('abc',count(2,3)), [('a', 2), ('b', 5), ('c', 8)])
- self.assertEqual(zip('abc',count(start=2,step=3)),
- [('a', 2), ('b', 5), ('c', 8)])
- self.assertEqual(zip('abc',count(step=-1)),
- [('a', 0), ('b', -1), ('c', -2)])
- self.assertEqual(zip('abc',count(2,0)), [('a', 2), ('b', 2), ('c', 2)])
- self.assertEqual(zip('abc',count(2,1)), [('a', 2), ('b', 3), ('c', 4)])
- self.assertEqual(take(20, count(maxsize-15, 3)), take(20, range(maxsize-15, maxsize+100, 3)))
- self.assertEqual(take(20, count(-maxsize-15, 3)), take(20, range(-maxsize-15,-maxsize+100, 3)))
- self.assertEqual(take(3, count(2, 3.25-4j)), [2, 5.25-4j, 8.5-8j])
- self.assertEqual(take(3, count(Decimal('1.1'), Decimal('.1'))),
- [Decimal('1.1'), Decimal('1.2'), Decimal('1.3')])
- self.assertEqual(take(3, count(Fraction(2,3), Fraction(1,7))),
- [Fraction(2,3), Fraction(17,21), Fraction(20,21)])
- self.assertEqual(repr(take(3, count(10, 2.5))), repr([10, 12.5, 15.0]))
- c = count(3, 5)
- self.assertEqual(repr(c), 'count(3, 5)')
- c.next()
- self.assertEqual(repr(c), 'count(8, 5)')
- c = count(-9, 0)
- self.assertEqual(repr(c), 'count(-9, 0)')
- c.next()
- self.assertEqual(repr(c), 'count(-9, 0)')
- c = count(-9, -3)
- self.assertEqual(repr(c), 'count(-9, -3)')
- c.next()
- self.assertEqual(repr(c), 'count(-12, -3)')
- self.assertEqual(repr(c), 'count(-12, -3)')
- self.assertEqual(repr(count(10.5, 1.25)), 'count(10.5, 1.25)')
- self.assertEqual(repr(count(10.5, 1)), 'count(10.5)') # suppress step=1 when it's an int
- self.assertEqual(repr(count(10.5, 1.00)), 'count(10.5, 1.0)') # do show float values lilke 1.0
- for i in (-sys.maxint-5, -sys.maxint+5 ,-10, -1, 0, 10, sys.maxint-5, sys.maxint+5):
- for j in (-sys.maxint-5, -sys.maxint+5 ,-10, -1, 0, 1, 10, sys.maxint-5, sys.maxint+5):
- # Test repr (ignoring the L in longs)
- r1 = repr(count(i, j)).replace('L', '')
- if j == 1:
- r2 = ('count(%r)' % i).replace('L', '')
- else:
- r2 = ('count(%r, %r)' % (i, j)).replace('L', '')
- self.assertEqual(r1, r2)
-
- def test_cycle(self):
- self.assertEqual(take(10, cycle('abc')), list('abcabcabca'))
- self.assertEqual(list(cycle('')), [])
- self.assertRaises(TypeError, cycle)
- self.assertRaises(TypeError, cycle, 5)
- self.assertEqual(list(islice(cycle(gen3()),10)), [0,1,2,0,1,2,0,1,2,0])
-
- def test_groupby(self):
- # Check whether it accepts arguments correctly
- self.assertEqual([], list(groupby([])))
- self.assertEqual([], list(groupby([], key=id)))
- self.assertRaises(TypeError, list, groupby('abc', []))
- self.assertRaises(TypeError, groupby, None)
- self.assertRaises(TypeError, groupby, 'abc', lambda x:x, 10)
-
- # Check normal input
- s = [(0, 10, 20), (0, 11,21), (0,12,21), (1,13,21), (1,14,22),
- (2,15,22), (3,16,23), (3,17,23)]
- dup = []
- for k, g in groupby(s, lambda r:r[0]):
- for elem in g:
- self.assertEqual(k, elem[0])
- dup.append(elem)
- self.assertEqual(s, dup)
-
- # Check nested case
- dup = []
- for k, g in groupby(s, lambda r:r[0]):
- for ik, ig in groupby(g, lambda r:r[2]):
- for elem in ig:
- self.assertEqual(k, elem[0])
- self.assertEqual(ik, elem[2])
- dup.append(elem)
- self.assertEqual(s, dup)
-
- # Check case where inner iterator is not used
- keys = [k for k, g in groupby(s, lambda r:r[0])]
- expectedkeys = set([r[0] for r in s])
- self.assertEqual(set(keys), expectedkeys)
- self.assertEqual(len(keys), len(expectedkeys))
-
- # Exercise pipes and filters style
- s = 'abracadabra'
- # sort s | uniq
- r = [k for k, g in groupby(sorted(s))]
- self.assertEqual(r, ['a', 'b', 'c', 'd', 'r'])
- # sort s | uniq -d
- r = [k for k, g in groupby(sorted(s)) if list(islice(g,1,2))]
- self.assertEqual(r, ['a', 'b', 'r'])
- # sort s | uniq -c
- r = [(len(list(g)), k) for k, g in groupby(sorted(s))]
- self.assertEqual(r, [(5, 'a'), (2, 'b'), (1, 'c'), (1, 'd'), (2, 'r')])
- # sort s | uniq -c | sort -rn | head -3
- r = sorted([(len(list(g)) , k) for k, g in groupby(sorted(s))], reverse=True)[:3]
- self.assertEqual(r, [(5, 'a'), (2, 'r'), (2, 'b')])
-
- # iter.next failure
- class ExpectedError(Exception):
- pass
- def delayed_raise(n=0):
- for i in range(n):
- yield 'yo'
- raise ExpectedError
- def gulp(iterable, keyp=None, func=list):
- return [func(g) for k, g in groupby(iterable, keyp)]
-
- # iter.next failure on outer object
- self.assertRaises(ExpectedError, gulp, delayed_raise(0))
- # iter.next failure on inner object
- self.assertRaises(ExpectedError, gulp, delayed_raise(1))
-
- # __cmp__ failure
- class DummyCmp:
- def __cmp__(self, dst):
- raise ExpectedError
- s = [DummyCmp(), DummyCmp(), None]
-
- # __cmp__ failure on outer object
- self.assertRaises(ExpectedError, gulp, s, func=id)
- # __cmp__ failure on inner object
- self.assertRaises(ExpectedError, gulp, s)
-
- # keyfunc failure
- def keyfunc(obj):
- if keyfunc.skip > 0:
- keyfunc.skip -= 1
- return obj
- else:
- raise ExpectedError
-
- # keyfunc failure on outer object
- keyfunc.skip = 0
- self.assertRaises(ExpectedError, gulp, [None], keyfunc)
- keyfunc.skip = 1
- self.assertRaises(ExpectedError, gulp, [None, None], keyfunc)
-
- def test_ifilter(self):
- self.assertEqual(list(ifilter(isEven, range(6))), [0,2,4])
- self.assertEqual(list(ifilter(None, [0,1,0,2,0])), [1,2])
- self.assertEqual(list(ifilter(bool, [0,1,0,2,0])), [1,2])
- self.assertEqual(take(4, ifilter(isEven, count())), [0,2,4,6])
- self.assertRaises(TypeError, ifilter)
- self.assertRaises(TypeError, ifilter, lambda x:x)
- self.assertRaises(TypeError, ifilter, lambda x:x, range(6), 7)
- self.assertRaises(TypeError, ifilter, isEven, 3)
- self.assertRaises(TypeError, ifilter(range(6), range(6)).next)
-
- def test_ifilterfalse(self):
- self.assertEqual(list(ifilterfalse(isEven, range(6))), [1,3,5])
- self.assertEqual(list(ifilterfalse(None, [0,1,0,2,0])), [0,0,0])
- self.assertEqual(list(ifilterfalse(bool, [0,1,0,2,0])), [0,0,0])
- self.assertEqual(take(4, ifilterfalse(isEven, count())), [1,3,5,7])
- self.assertRaises(TypeError, ifilterfalse)
- self.assertRaises(TypeError, ifilterfalse, lambda x:x)
- self.assertRaises(TypeError, ifilterfalse, lambda x:x, range(6), 7)
- self.assertRaises(TypeError, ifilterfalse, isEven, 3)
- self.assertRaises(TypeError, ifilterfalse(range(6), range(6)).next)
-
- def test_izip(self):
- ans = [(x,y) for x, y in izip('abc',count())]
- self.assertEqual(ans, [('a', 0), ('b', 1), ('c', 2)])
- self.assertEqual(list(izip('abc', range(6))), zip('abc', range(6)))
- self.assertEqual(list(izip('abcdef', range(3))), zip('abcdef', range(3)))
- self.assertEqual(take(3,izip('abcdef', count())), zip('abcdef', range(3)))
- self.assertEqual(list(izip('abcdef')), zip('abcdef'))
- self.assertEqual(list(izip()), zip())
- self.assertRaises(TypeError, izip, 3)
- self.assertRaises(TypeError, izip, range(3), 3)
- self.assertEqual([tuple(list(pair)) for pair in izip('abc', 'def')],
- zip('abc', 'def'))
- self.assertEqual([pair for pair in izip('abc', 'def')],
- zip('abc', 'def'))
-
- @test_support.impl_detail("tuple reuse is specific to CPython")
- def test_izip_tuple_resuse(self):
- ids = map(id, izip('abc', 'def'))
- self.assertEqual(min(ids), max(ids))
- ids = map(id, list(izip('abc', 'def')))
- self.assertEqual(len(dict.fromkeys(ids)), len(ids))
-
- def test_iziplongest(self):
- for args in [
- ['abc', range(6)],
- [range(6), 'abc'],
- [range(1000), range(2000,2100), range(3000,3050)],
- [range(1000), range(0), range(3000,3050), range(1200), range(1500)],
- [range(1000), range(0), range(3000,3050), range(1200), range(1500), range(0)],
- ]:
- # target = map(None, *args) <- this raises a py3k warning
- # this is the replacement:
- target = [tuple([arg[i] if i < len(arg) else None for arg in args])
- for i in range(max(map(len, args)))]
- self.assertEqual(list(izip_longest(*args)), target)
- self.assertEqual(list(izip_longest(*args, **{})), target)
- target = [tuple((e is None and 'X' or e) for e in t) for t in target] # Replace None fills with 'X'
- self.assertEqual(list(izip_longest(*args, **dict(fillvalue='X'))), target)
-
- self.assertEqual(take(3,izip_longest('abcdef', count())), zip('abcdef', range(3))) # take 3 from infinite input
-
- self.assertEqual(list(izip_longest()), zip())
- self.assertEqual(list(izip_longest([])), zip([]))
- self.assertEqual(list(izip_longest('abcdef')), zip('abcdef'))
-
- self.assertEqual(list(izip_longest('abc', 'defg', **{})),
- zip(list('abc') + [None], 'defg')) # empty keyword dict
- self.assertRaises(TypeError, izip_longest, 3)
- self.assertRaises(TypeError, izip_longest, range(3), 3)
-
- for stmt in [
- "izip_longest('abc', fv=1)",
- "izip_longest('abc', fillvalue=1, bogus_keyword=None)",
- ]:
- try:
- eval(stmt, globals(), locals())
- except TypeError:
- pass
- else:
- self.fail('Did not raise Type in: ' + stmt)
-
- self.assertEqual([tuple(list(pair)) for pair in izip_longest('abc', 'def')],
- zip('abc', 'def'))
- self.assertEqual([pair for pair in izip_longest('abc', 'def')],
- zip('abc', 'def'))
-
- @test_support.impl_detail("tuple reuse is specific to CPython")
- def test_izip_longest_tuple_reuse(self):
- ids = map(id, izip_longest('abc', 'def'))
- self.assertEqual(min(ids), max(ids))
- ids = map(id, list(izip_longest('abc', 'def')))
- self.assertEqual(len(dict.fromkeys(ids)), len(ids))
-
- def test_bug_7244(self):
-
- class Repeater(object):
- # this class is similar to itertools.repeat
- def __init__(self, o, t, e):
- self.o = o
- self.t = int(t)
- self.e = e
- def __iter__(self): # its iterator is itself
- return self
- def next(self):
- if self.t > 0:
- self.t -= 1
- return self.o
- else:
- raise self.e
-
- # Formerly this code in would fail in debug mode
- # with Undetected Error and Stop Iteration
- r1 = Repeater(1, 3, StopIteration)
- r2 = Repeater(2, 4, StopIteration)
- def run(r1, r2):
- result = []
- for i, j in izip_longest(r1, r2, fillvalue=0):
- with test_support.captured_output('stdout'):
- print (i, j)
- result.append((i, j))
- return result
- self.assertEqual(run(r1, r2), [(1,2), (1,2), (1,2), (0,2)])
-
- # Formerly, the RuntimeError would be lost
- # and StopIteration would stop as expected
- r1 = Repeater(1, 3, RuntimeError)
- r2 = Repeater(2, 4, StopIteration)
- it = izip_longest(r1, r2, fillvalue=0)
- self.assertEqual(next(it), (1, 2))
- self.assertEqual(next(it), (1, 2))
- self.assertEqual(next(it), (1, 2))
- self.assertRaises(RuntimeError, next, it)
-
- def test_product(self):
- for args, result in [
- ([], [()]), # zero iterables
- (['ab'], [('a',), ('b',)]), # one iterable
- ([range(2), range(3)], [(0,0), (0,1), (0,2), (1,0), (1,1), (1,2)]), # two iterables
- ([range(0), range(2), range(3)], []), # first iterable with zero length
- ([range(2), range(0), range(3)], []), # middle iterable with zero length
- ([range(2), range(3), range(0)], []), # last iterable with zero length
- ]:
- self.assertEqual(list(product(*args)), result)
- for r in range(4):
- self.assertEqual(list(product(*(args*r))),
- list(product(*args, **dict(repeat=r))))
- self.assertEqual(len(list(product(*[range(7)]*6))), 7**6)
- self.assertRaises(TypeError, product, range(6), None)
-
- def product1(*args, **kwds):
- pools = map(tuple, args) * kwds.get('repeat', 1)
- n = len(pools)
- if n == 0:
- yield ()
- return
- if any(len(pool) == 0 for pool in pools):
- return
- indices = [0] * n
- yield tuple(pool[i] for pool, i in zip(pools, indices))
- while 1:
- for i in reversed(range(n)): # right to left
- if indices[i] == len(pools[i]) - 1:
- continue
- indices[i] += 1
- for j in range(i+1, n):
- indices[j] = 0
- yield tuple(pool[i] for pool, i in zip(pools, indices))
- break
- else:
- return
-
- def product2(*args, **kwds):
- 'Pure python version used in docs'
- pools = map(tuple, args) * kwds.get('repeat', 1)
- result = [[]]
- for pool in pools:
- result = [x+[y] for x in result for y in pool]
- for prod in result:
- yield tuple(prod)
-
- argtypes = ['', 'abc', '', xrange(0), xrange(4), dict(a=1, b=2, c=3),
- set('abcdefg'), range(11), tuple(range(13))]
- for i in range(100):
- args = [random.choice(argtypes) for j in range(random.randrange(5))]
- expected_len = prod(map(len, args))
- self.assertEqual(len(list(product(*args))), expected_len)
- self.assertEqual(list(product(*args)), list(product1(*args)))
- self.assertEqual(list(product(*args)), list(product2(*args)))
- args = map(iter, args)
- self.assertEqual(len(list(product(*args))), expected_len)
-
- @test_support.impl_detail("tuple reuse is specific to CPython")
- def test_product_tuple_reuse(self):
- self.assertEqual(len(set(map(id, product('abc', 'def')))), 1)
- self.assertNotEqual(len(set(map(id, list(product('abc', 'def'))))), 1)
-
- def test_repeat(self):
- self.assertEqual(list(repeat(object='a', times=3)), ['a', 'a', 'a'])
- self.assertEqual(zip(xrange(3),repeat('a')),
- [(0, 'a'), (1, 'a'), (2, 'a')])
- self.assertEqual(list(repeat('a', 3)), ['a', 'a', 'a'])
- self.assertEqual(take(3, repeat('a')), ['a', 'a', 'a'])
- self.assertEqual(list(repeat('a', 0)), [])
- self.assertEqual(list(repeat('a', -3)), [])
- self.assertRaises(TypeError, repeat)
- self.assertRaises(TypeError, repeat, None, 3, 4)
- self.assertRaises(TypeError, repeat, None, 'a')
- r = repeat(1+0j)
- self.assertEqual(repr(r), 'repeat((1+0j))')
- r = repeat(1+0j, 5)
- self.assertEqual(repr(r), 'repeat((1+0j), 5)')
- list(r)
- self.assertEqual(repr(r), 'repeat((1+0j), 0)')
-
- def test_imap(self):
- self.assertEqual(list(imap(operator.pow, range(3), range(1,7))),
- [0**1, 1**2, 2**3])
- self.assertEqual(list(imap(None, 'abc', range(5))),
- [('a',0),('b',1),('c',2)])
- self.assertEqual(list(imap(None, 'abc', count())),
- [('a',0),('b',1),('c',2)])
- self.assertEqual(take(2,imap(None, 'abc', count())),
- [('a',0),('b',1)])
- self.assertEqual(list(imap(operator.pow, [])), [])
- self.assertRaises(TypeError, imap)
- self.assertRaises(TypeError, imap, operator.neg)
- self.assertRaises(TypeError, imap(10, range(5)).next)
- self.assertRaises(ValueError, imap(errfunc, [4], [5]).next)
- self.assertRaises(TypeError, imap(onearg, [4], [5]).next)
-
- def test_starmap(self):
- self.assertEqual(list(starmap(operator.pow, zip(range(3), range(1,7)))),
- [0**1, 1**2, 2**3])
- self.assertEqual(take(3, starmap(operator.pow, izip(count(), count(1)))),
- [0**1, 1**2, 2**3])
- self.assertEqual(list(starmap(operator.pow, [])), [])
- self.assertEqual(list(starmap(operator.pow, [iter([4,5])])), [4**5])
- self.assertRaises(TypeError, list, starmap(operator.pow, [None]))
- self.assertRaises(TypeError, starmap)
- self.assertRaises(TypeError, starmap, operator.pow, [(4,5)], 'extra')
- self.assertRaises(TypeError, starmap(10, [(4,5)]).next)
- self.assertRaises(ValueError, starmap(errfunc, [(4,5)]).next)
- self.assertRaises(TypeError, starmap(onearg, [(4,5)]).next)
-
- def test_islice(self):
- for args in [ # islice(args) should agree with range(args)
- (10, 20, 3),
- (10, 3, 20),
- (10, 20),
- (10, 3),
- (20,)
- ]:
- self.assertEqual(list(islice(xrange(100), *args)), range(*args))
-
- for args, tgtargs in [ # Stop when seqn is exhausted
- ((10, 110, 3), ((10, 100, 3))),
- ((10, 110), ((10, 100))),
- ((110,), (100,))
- ]:
- self.assertEqual(list(islice(xrange(100), *args)), range(*tgtargs))
-
- # Test stop=None
- self.assertEqual(list(islice(xrange(10), None)), range(10))
- self.assertEqual(list(islice(xrange(10), None, None)), range(10))
- self.assertEqual(list(islice(xrange(10), None, None, None)), range(10))
- self.assertEqual(list(islice(xrange(10), 2, None)), range(2, 10))
- self.assertEqual(list(islice(xrange(10), 1, None, 2)), range(1, 10, 2))
-
- # Test number of items consumed SF #1171417
- it = iter(range(10))
- self.assertEqual(list(islice(it, 3)), range(3))
- self.assertEqual(list(it), range(3, 10))
-
- # Test invalid arguments
- self.assertRaises(TypeError, islice, xrange(10))
- self.assertRaises(TypeError, islice, xrange(10), 1, 2, 3, 4)
- self.assertRaises(ValueError, islice, xrange(10), -5, 10, 1)
- self.assertRaises(ValueError, islice, xrange(10), 1, -5, -1)
- self.assertRaises(ValueError, islice, xrange(10), 1, 10, -1)
- self.assertRaises(ValueError, islice, xrange(10), 1, 10, 0)
- self.assertRaises(ValueError, islice, xrange(10), 'a')
- self.assertRaises(ValueError, islice, xrange(10), 'a', 1)
- self.assertRaises(ValueError, islice, xrange(10), 1, 'a')
- self.assertRaises(ValueError, islice, xrange(10), 'a', 1, 1)
- self.assertRaises(ValueError, islice, xrange(10), 1, 'a', 1)
- self.assertEqual(len(list(islice(count(), 1, 10, maxsize))), 1)
-
- # Issue #10323: Less islice in a predictable state
- c = count()
- self.assertEqual(list(islice(c, 1, 3, 50)), [1])
- self.assertEqual(next(c), 3)
-
- def test_takewhile(self):
- data = [1, 3, 5, 20, 2, 4, 6, 8]
- underten = lambda x: x<10
- self.assertEqual(list(takewhile(underten, data)), [1, 3, 5])
- self.assertEqual(list(takewhile(underten, [])), [])
- self.assertRaises(TypeError, takewhile)
- self.assertRaises(TypeError, takewhile, operator.pow)
- self.assertRaises(TypeError, takewhile, operator.pow, [(4,5)], 'extra')
- self.assertRaises(TypeError, takewhile(10, [(4,5)]).next)
- self.assertRaises(ValueError, takewhile(errfunc, [(4,5)]).next)
- t = takewhile(bool, [1, 1, 1, 0, 0, 0])
- self.assertEqual(list(t), [1, 1, 1])
- self.assertRaises(StopIteration, t.next)
-
- def test_dropwhile(self):
- data = [1, 3, 5, 20, 2, 4, 6, 8]
- underten = lambda x: x<10
- self.assertEqual(list(dropwhile(underten, data)), [20, 2, 4, 6, 8])
- self.assertEqual(list(dropwhile(underten, [])), [])
- self.assertRaises(TypeError, dropwhile)
- self.assertRaises(TypeError, dropwhile, operator.pow)
- self.assertRaises(TypeError, dropwhile, operator.pow, [(4,5)], 'extra')
- self.assertRaises(TypeError, dropwhile(10, [(4,5)]).next)
- self.assertRaises(ValueError, dropwhile(errfunc, [(4,5)]).next)
-
- def test_tee(self):
- n = 200
- def irange(n):
- for i in xrange(n):
- yield i
-
- a, b = tee([]) # test empty iterator
- self.assertEqual(list(a), [])
- self.assertEqual(list(b), [])
-
- a, b = tee(irange(n)) # test 100% interleaved
- self.assertEqual(zip(a,b), zip(range(n),range(n)))
-
- a, b = tee(irange(n)) # test 0% interleaved
- self.assertEqual(list(a), range(n))
- self.assertEqual(list(b), range(n))
-
- a, b = tee(irange(n)) # test dealloc of leading iterator
- for i in xrange(100):
- self.assertEqual(a.next(), i)
- del a
- self.assertEqual(list(b), range(n))
-
- a, b = tee(irange(n)) # test dealloc of trailing iterator
- for i in xrange(100):
- self.assertEqual(a.next(), i)
- del b
- self.assertEqual(list(a), range(100, n))
-
- for j in xrange(5): # test randomly interleaved
- order = [0]*n + [1]*n
- random.shuffle(order)
- lists = ([], [])
- its = tee(irange(n))
- for i in order:
- value = its[i].next()
- lists[i].append(value)
- self.assertEqual(lists[0], range(n))
- self.assertEqual(lists[1], range(n))
-
- # test argument format checking
- self.assertRaises(TypeError, tee)
- self.assertRaises(TypeError, tee, 3)
- self.assertRaises(TypeError, tee, [1,2], 'x')
- self.assertRaises(TypeError, tee, [1,2], 3, 'x')
-
- # tee object should be instantiable
- a, b = tee('abc')
- c = type(a)('def')
- self.assertEqual(list(c), list('def'))
-
- # test long-lagged and multi-way split
- a, b, c = tee(xrange(2000), 3)
- for i in xrange(100):
- self.assertEqual(a.next(), i)
- self.assertEqual(list(b), range(2000))
- self.assertEqual([c.next(), c.next()], range(2))
- self.assertEqual(list(a), range(100,2000))
- self.assertEqual(list(c), range(2,2000))
-
- # test values of n
- self.assertRaises(TypeError, tee, 'abc', 'invalid')
- self.assertRaises(ValueError, tee, [], -1)
- for n in xrange(5):
- result = tee('abc', n)
- self.assertEqual(type(result), tuple)
- self.assertEqual(len(result), n)
- self.assertEqual(map(list, result), [list('abc')]*n)
-
- # tee pass-through to copyable iterator
- a, b = tee('abc')
- c, d = tee(a)
- self.assertTrue(a is c)
-
- # test tee_new
- t1, t2 = tee('abc')
- tnew = type(t1)
- self.assertRaises(TypeError, tnew)
- self.assertRaises(TypeError, tnew, 10)
- t3 = tnew(t1)
- self.assertTrue(list(t1) == list(t2) == list(t3) == list('abc'))
-
- # test that tee objects are weak referencable
- a, b = tee(xrange(10))
- p = proxy(a)
- self.assertEqual(getattr(p, '__class__'), type(b))
- del a
- self.assertRaises(ReferenceError, getattr, p, '__class__')
-
- # Issue 13454: Crash when deleting backward iterator from tee()
- def test_tee_del_backward(self):
- forward, backward = tee(repeat(None, 20000000))
- any(forward) # exhaust the iterator
- del backward
-
- def test_StopIteration(self):
- self.assertRaises(StopIteration, izip().next)
-
- for f in (chain, cycle, izip, groupby):
- self.assertRaises(StopIteration, f([]).next)
- self.assertRaises(StopIteration, f(StopNow()).next)
-
- self.assertRaises(StopIteration, islice([], None).next)
- self.assertRaises(StopIteration, islice(StopNow(), None).next)
-
- p, q = tee([])
- self.assertRaises(StopIteration, p.next)
- self.assertRaises(StopIteration, q.next)
- p, q = tee(StopNow())
- self.assertRaises(StopIteration, p.next)
- self.assertRaises(StopIteration, q.next)
-
- self.assertRaises(StopIteration, repeat(None, 0).next)
-
- for f in (ifilter, ifilterfalse, imap, takewhile, dropwhile, starmap):
- self.assertRaises(StopIteration, f(lambda x:x, []).next)
- self.assertRaises(StopIteration, f(lambda x:x, StopNow()).next)
-
-class TestExamples(unittest.TestCase):
-
- def test_chain(self):
- self.assertEqual(''.join(chain('ABC', 'DEF')), 'ABCDEF')
-
- def test_chain_from_iterable(self):
- self.assertEqual(''.join(chain.from_iterable(['ABC', 'DEF'])), 'ABCDEF')
-
- def test_combinations(self):
- self.assertEqual(list(combinations('ABCD', 2)),
- [('A','B'), ('A','C'), ('A','D'), ('B','C'), ('B','D'), ('C','D')])
- self.assertEqual(list(combinations(range(4), 3)),
- [(0,1,2), (0,1,3), (0,2,3), (1,2,3)])
-
- def test_combinations_with_replacement(self):
- self.assertEqual(list(combinations_with_replacement('ABC', 2)),
- [('A','A'), ('A','B'), ('A','C'), ('B','B'), ('B','C'), ('C','C')])
-
- def test_compress(self):
- self.assertEqual(list(compress('ABCDEF', [1,0,1,0,1,1])), list('ACEF'))
-
- def test_count(self):
- self.assertEqual(list(islice(count(10), 5)), [10, 11, 12, 13, 14])
-
- def test_cycle(self):
- self.assertEqual(list(islice(cycle('ABCD'), 12)), list('ABCDABCDABCD'))
-
- def test_dropwhile(self):
- self.assertEqual(list(dropwhile(lambda x: x<5, [1,4,6,4,1])), [6,4,1])
-
- def test_groupby(self):
- self.assertEqual([k for k, g in groupby('AAAABBBCCDAABBB')],
- list('ABCDAB'))
- self.assertEqual([(list(g)) for k, g in groupby('AAAABBBCCD')],
- [list('AAAA'), list('BBB'), list('CC'), list('D')])
-
- def test_ifilter(self):
- self.assertEqual(list(ifilter(lambda x: x%2, range(10))), [1,3,5,7,9])
-
- def test_ifilterfalse(self):
- self.assertEqual(list(ifilterfalse(lambda x: x%2, range(10))), [0,2,4,6,8])
-
- def test_imap(self):
- self.assertEqual(list(imap(pow, (2,3,10), (5,2,3))), [32, 9, 1000])
-
- def test_islice(self):
- self.assertEqual(list(islice('ABCDEFG', 2)), list('AB'))
- self.assertEqual(list(islice('ABCDEFG', 2, 4)), list('CD'))
- self.assertEqual(list(islice('ABCDEFG', 2, None)), list('CDEFG'))
- self.assertEqual(list(islice('ABCDEFG', 0, None, 2)), list('ACEG'))
-
- def test_izip(self):
- self.assertEqual(list(izip('ABCD', 'xy')), [('A', 'x'), ('B', 'y')])
-
- def test_izip_longest(self):
- self.assertEqual(list(izip_longest('ABCD', 'xy', fillvalue='-')),
- [('A', 'x'), ('B', 'y'), ('C', '-'), ('D', '-')])
-
- def test_permutations(self):
- self.assertEqual(list(permutations('ABCD', 2)),
- map(tuple, 'AB AC AD BA BC BD CA CB CD DA DB DC'.split()))
- self.assertEqual(list(permutations(range(3))),
- [(0,1,2), (0,2,1), (1,0,2), (1,2,0), (2,0,1), (2,1,0)])
-
- def test_product(self):
- self.assertEqual(list(product('ABCD', 'xy')),
- map(tuple, 'Ax Ay Bx By Cx Cy Dx Dy'.split()))
- self.assertEqual(list(product(range(2), repeat=3)),
- [(0,0,0), (0,0,1), (0,1,0), (0,1,1),
- (1,0,0), (1,0,1), (1,1,0), (1,1,1)])
-
- def test_repeat(self):
- self.assertEqual(list(repeat(10, 3)), [10, 10, 10])
-
- def test_stapmap(self):
- self.assertEqual(list(starmap(pow, [(2,5), (3,2), (10,3)])),
- [32, 9, 1000])
-
- def test_takewhile(self):
- self.assertEqual(list(takewhile(lambda x: x<5, [1,4,6,4,1])), [1,4])
-
-
-class TestGC(unittest.TestCase):
-
- def makecycle(self, iterator, container):
- container.append(iterator)
- iterator.next()
- del container, iterator
-
- def test_chain(self):
- a = []
- self.makecycle(chain(a), a)
-
- def test_chain_from_iterable(self):
- a = []
- self.makecycle(chain.from_iterable([a]), a)
-
- def test_combinations(self):
- a = []
- self.makecycle(combinations([1,2,a,3], 3), a)
-
- def test_combinations_with_replacement(self):
- a = []
- self.makecycle(combinations_with_replacement([1,2,a,3], 3), a)
-
- def test_compress(self):
- a = []
- self.makecycle(compress('ABCDEF', [1,0,1,0,1,0]), a)
-
- def test_count(self):
- a = []
- Int = type('Int', (int,), dict(x=a))
- self.makecycle(count(Int(0), Int(1)), a)
-
- def test_cycle(self):
- a = []
- self.makecycle(cycle([a]*2), a)
-
- def test_dropwhile(self):
- a = []
- self.makecycle(dropwhile(bool, [0, a, a]), a)
-
- def test_groupby(self):
- a = []
- self.makecycle(groupby([a]*2, lambda x:x), a)
-
- def test_issue2246(self):
- # Issue 2246 -- the _grouper iterator was not included in GC
- n = 10
- keyfunc = lambda x: x
- for i, j in groupby(xrange(n), key=keyfunc):
- keyfunc.__dict__.setdefault('x',[]).append(j)
-
- def test_ifilter(self):
- a = []
- self.makecycle(ifilter(lambda x:True, [a]*2), a)
-
- def test_ifilterfalse(self):
- a = []
- self.makecycle(ifilterfalse(lambda x:False, a), a)
-
- def test_izip(self):
- a = []
- self.makecycle(izip([a]*2, [a]*3), a)
-
- def test_izip_longest(self):
- a = []
- self.makecycle(izip_longest([a]*2, [a]*3), a)
- b = [a, None]
- self.makecycle(izip_longest([a]*2, [a]*3, fillvalue=b), a)
-
- def test_imap(self):
- a = []
- self.makecycle(imap(lambda x:x, [a]*2), a)
-
- def test_islice(self):
- a = []
- self.makecycle(islice([a]*2, None), a)
-
- def test_permutations(self):
- a = []
- self.makecycle(permutations([1,2,a,3], 3), a)
-
- def test_product(self):
- a = []
- self.makecycle(product([1,2,a,3], repeat=3), a)
-
- def test_repeat(self):
- a = []
- self.makecycle(repeat(a), a)
-
- def test_starmap(self):
- a = []
- self.makecycle(starmap(lambda *t: t, [(a,a)]*2), a)
-
- def test_takewhile(self):
- a = []
- self.makecycle(takewhile(bool, [1, 0, a, a]), a)
-
-def R(seqn):
- 'Regular generator'
- for i in seqn:
- yield i
-
-class G:
- 'Sequence using __getitem__'
- def __init__(self, seqn):
- self.seqn = seqn
- def __getitem__(self, i):
- return self.seqn[i]
-
-class I:
- 'Sequence using iterator protocol'
- def __init__(self, seqn):
- self.seqn = seqn
- self.i = 0
- def __iter__(self):
- return self
- def next(self):
- if self.i >= len(self.seqn): raise StopIteration
- v = self.seqn[self.i]
- self.i += 1
- return v
-
-class Ig:
- 'Sequence using iterator protocol defined with a generator'
- def __init__(self, seqn):
- self.seqn = seqn
- self.i = 0
- def __iter__(self):
- for val in self.seqn:
- yield val
-
-class X:
- 'Missing __getitem__ and __iter__'
- def __init__(self, seqn):
- self.seqn = seqn
- self.i = 0
- def next(self):
- if self.i >= len(self.seqn): raise StopIteration
- v = self.seqn[self.i]
- self.i += 1
- return v
-
-class N:
- 'Iterator missing next()'
- def __init__(self, seqn):
- self.seqn = seqn
- self.i = 0
- def __iter__(self):
- return self
-
-class E:
- 'Test propagation of exceptions'
- def __init__(self, seqn):
- self.seqn = seqn
- self.i = 0
- def __iter__(self):
- return self
- def next(self):
- 3 // 0
-
-class S:
- 'Test immediate stop'
- def __init__(self, seqn):
- pass
- def __iter__(self):
- return self
- def next(self):
- raise StopIteration
-
-def L(seqn):
- 'Test multiple tiers of iterators'
- return chain(imap(lambda x:x, R(Ig(G(seqn)))))
-
-
-class TestVariousIteratorArgs(unittest.TestCase):
-
- def test_chain(self):
- for s in ("123", "", range(1000), ('do', 1.2), xrange(2000,2200,5)):
- for g in (G, I, Ig, S, L, R):
- self.assertEqual(list(chain(g(s))), list(g(s)))
- self.assertEqual(list(chain(g(s), g(s))), list(g(s))+list(g(s)))
- self.assertRaises(TypeError, list, chain(X(s)))
- self.assertRaises(TypeError, list, chain(N(s)))
- self.assertRaises(ZeroDivisionError, list, chain(E(s)))
-
- def test_compress(self):
- for s in ("123", "", range(1000), ('do', 1.2), xrange(2000,2200,5)):
- n = len(s)
- for g in (G, I, Ig, S, L, R):
- self.assertEqual(list(compress(g(s), repeat(1))), list(g(s)))
- self.assertRaises(TypeError, compress, X(s), repeat(1))
- self.assertRaises(TypeError, list, compress(N(s), repeat(1)))
- self.assertRaises(ZeroDivisionError, list, compress(E(s), repeat(1)))
-
- def test_product(self):
- for s in ("123", "", range(1000), ('do', 1.2), xrange(2000,2200,5)):
- self.assertRaises(TypeError, product, X(s))
- self.assertRaises(TypeError, product, N(s))
- self.assertRaises(ZeroDivisionError, product, E(s))
-
- def test_cycle(self):
- for s in ("123", "", range(1000), ('do', 1.2), xrange(2000,2200,5)):
- for g in (G, I, Ig, S, L, R):
- tgtlen = len(s) * 3
- expected = list(g(s))*3
- actual = list(islice(cycle(g(s)), tgtlen))
- self.assertEqual(actual, expected)
- self.assertRaises(TypeError, cycle, X(s))
- self.assertRaises(TypeError, list, cycle(N(s)))
- self.assertRaises(ZeroDivisionError, list, cycle(E(s)))
-
- def test_groupby(self):
- for s in (range(10), range(0), range(1000), (7,11), xrange(2000,2200,5)):
- for g in (G, I, Ig, S, L, R):
- self.assertEqual([k for k, sb in groupby(g(s))], list(g(s)))
- self.assertRaises(TypeError, groupby, X(s))
- self.assertRaises(TypeError, list, groupby(N(s)))
- self.assertRaises(ZeroDivisionError, list, groupby(E(s)))
-
- def test_ifilter(self):
- for s in (range(10), range(0), range(1000), (7,11), xrange(2000,2200,5)):
- for g in (G, I, Ig, S, L, R):
- self.assertEqual(list(ifilter(isEven, g(s))), filter(isEven, g(s)))
- self.assertRaises(TypeError, ifilter, isEven, X(s))
- self.assertRaises(TypeError, list, ifilter(isEven, N(s)))
- self.assertRaises(ZeroDivisionError, list, ifilter(isEven, E(s)))
-
- def test_ifilterfalse(self):
- for s in (range(10), range(0), range(1000), (7,11), xrange(2000,2200,5)):
- for g in (G, I, Ig, S, L, R):
- self.assertEqual(list(ifilterfalse(isEven, g(s))), filter(isOdd, g(s)))
- self.assertRaises(TypeError, ifilterfalse, isEven, X(s))
- self.assertRaises(TypeError, list, ifilterfalse(isEven, N(s)))
- self.assertRaises(ZeroDivisionError, list, ifilterfalse(isEven, E(s)))
-
- def test_izip(self):
- for s in ("123", "", range(1000), ('do', 1.2), xrange(2000,2200,5)):
- for g in (G, I, Ig, S, L, R):
- self.assertEqual(list(izip(g(s))), zip(g(s)))
- self.assertEqual(list(izip(g(s), g(s))), zip(g(s), g(s)))
- self.assertRaises(TypeError, izip, X(s))
- self.assertRaises(TypeError, list, izip(N(s)))
- self.assertRaises(ZeroDivisionError, list, izip(E(s)))
-
- def test_iziplongest(self):
- for s in ("123", "", range(1000), ('do', 1.2), xrange(2000,2200,5)):
- for g in (G, I, Ig, S, L, R):
- self.assertEqual(list(izip_longest(g(s))), zip(g(s)))
- self.assertEqual(list(izip_longest(g(s), g(s))), zip(g(s), g(s)))
- self.assertRaises(TypeError, izip_longest, X(s))
- self.assertRaises(TypeError, list, izip_longest(N(s)))
- self.assertRaises(ZeroDivisionError, list, izip_longest(E(s)))
-
- def test_imap(self):
- for s in (range(10), range(0), range(100), (7,11), xrange(20,50,5)):
- for g in (G, I, Ig, S, L, R):
- self.assertEqual(list(imap(onearg, g(s))), map(onearg, g(s)))
- self.assertEqual(list(imap(operator.pow, g(s), g(s))), map(operator.pow, g(s), g(s)))
- self.assertRaises(TypeError, imap, onearg, X(s))
- self.assertRaises(TypeError, list, imap(onearg, N(s)))
- self.assertRaises(ZeroDivisionError, list, imap(onearg, E(s)))
-
- def test_islice(self):
- for s in ("12345", "", range(1000), ('do', 1.2), xrange(2000,2200,5)):
- for g in (G, I, Ig, S, L, R):
- self.assertEqual(list(islice(g(s),1,None,2)), list(g(s))[1::2])
- self.assertRaises(TypeError, islice, X(s), 10)
- self.assertRaises(TypeError, list, islice(N(s), 10))
- self.assertRaises(ZeroDivisionError, list, islice(E(s), 10))
-
- def test_starmap(self):
- for s in (range(10), range(0), range(100), (7,11), xrange(20,50,5)):
- for g in (G, I, Ig, S, L, R):
- ss = zip(s, s)
- self.assertEqual(list(starmap(operator.pow, g(ss))), map(operator.pow, g(s), g(s)))
- self.assertRaises(TypeError, starmap, operator.pow, X(ss))
- self.assertRaises(TypeError, list, starmap(operator.pow, N(ss)))
- self.assertRaises(ZeroDivisionError, list, starmap(operator.pow, E(ss)))
-
- def test_takewhile(self):
- for s in (range(10), range(0), range(1000), (7,11), xrange(2000,2200,5)):
- for g in (G, I, Ig, S, L, R):
- tgt = []
- for elem in g(s):
- if not isEven(elem): break
- tgt.append(elem)
- self.assertEqual(list(takewhile(isEven, g(s))), tgt)
- self.assertRaises(TypeError, takewhile, isEven, X(s))
- self.assertRaises(TypeError, list, takewhile(isEven, N(s)))
- self.assertRaises(ZeroDivisionError, list, takewhile(isEven, E(s)))
-
- def test_dropwhile(self):
- for s in (range(10), range(0), range(1000), (7,11), xrange(2000,2200,5)):
- for g in (G, I, Ig, S, L, R):
- tgt = []
- for elem in g(s):
- if not tgt and isOdd(elem): continue
- tgt.append(elem)
- self.assertEqual(list(dropwhile(isOdd, g(s))), tgt)
- self.assertRaises(TypeError, dropwhile, isOdd, X(s))
- self.assertRaises(TypeError, list, dropwhile(isOdd, N(s)))
- self.assertRaises(ZeroDivisionError, list, dropwhile(isOdd, E(s)))
-
- def test_tee(self):
- for s in ("123", "", range(1000), ('do', 1.2), xrange(2000,2200,5)):
- for g in (G, I, Ig, S, L, R):
- it1, it2 = tee(g(s))
- self.assertEqual(list(it1), list(g(s)))
- self.assertEqual(list(it2), list(g(s)))
- self.assertRaises(TypeError, tee, X(s))
- self.assertRaises(TypeError, list, tee(N(s))[0])
- self.assertRaises(ZeroDivisionError, list, tee(E(s))[0])
-
-class LengthTransparency(unittest.TestCase):
-
- def test_repeat(self):
- from test.test_iterlen import len
- self.assertEqual(len(repeat(None, 50)), 50)
- self.assertRaises(TypeError, len, repeat(None))
-
-class RegressionTests(unittest.TestCase):
-
- def test_sf_793826(self):
- # Fix Armin Rigo's successful efforts to wreak havoc
-
- def mutatingtuple(tuple1, f, tuple2):
- # this builds a tuple t which is a copy of tuple1,
- # then calls f(t), then mutates t to be equal to tuple2
- # (needs len(tuple1) == len(tuple2)).
- def g(value, first=[1]):
- if first:
- del first[:]
- f(z.next())
- return value
- items = list(tuple2)
- items[1:1] = list(tuple1)
- gen = imap(g, items)
- z = izip(*[gen]*len(tuple1))
- z.next()
-
- def f(t):
- global T
- T = t
- first[:] = list(T)
-
- first = []
- mutatingtuple((1,2,3), f, (4,5,6))
- second = list(T)
- self.assertEqual(first, second)
-
-
- def test_sf_950057(self):
- # Make sure that chain() and cycle() catch exceptions immediately
- # rather than when shifting between input sources
-
- def gen1():
- hist.append(0)
- yield 1
- hist.append(1)
- raise AssertionError
- hist.append(2)
-
- def gen2(x):
- hist.append(3)
- yield 2
- hist.append(4)
- if x:
- raise StopIteration
-
- hist = []
- self.assertRaises(AssertionError, list, chain(gen1(), gen2(False)))
- self.assertEqual(hist, [0,1])
-
- hist = []
- self.assertRaises(AssertionError, list, chain(gen1(), gen2(True)))
- self.assertEqual(hist, [0,1])
-
- hist = []
- self.assertRaises(AssertionError, list, cycle(gen1()))
- self.assertEqual(hist, [0,1])
-
-class SubclassWithKwargsTest(unittest.TestCase):
- def test_keywords_in_subclass(self):
- # count is not subclassable...
- for cls in (repeat, izip, ifilter, ifilterfalse, chain, imap,
- starmap, islice, takewhile, dropwhile, cycle, compress):
- class Subclass(cls):
- def __init__(self, newarg=None, *args):
- cls.__init__(self, *args)
- try:
- Subclass(newarg=1)
- except TypeError, err:
- # we expect type errors because of wrong argument count
- self.assertNotIn("does not take keyword arguments", err.args[0])
-
-
-libreftest = """ Doctest for examples in the library reference: libitertools.tex
-
-
->>> amounts = [120.15, 764.05, 823.14]
->>> for checknum, amount in izip(count(1200), amounts):
-... print 'Check %d is for $%.2f' % (checknum, amount)
-...
-Check 1200 is for $120.15
-Check 1201 is for $764.05
-Check 1202 is for $823.14
-
->>> import operator
->>> for cube in imap(operator.pow, xrange(1,4), repeat(3)):
-... print cube
-...
-1
-8
-27
-
->>> reportlines = ['EuroPython', 'Roster', '', 'alex', '', 'laura', '', 'martin', '', 'walter', '', 'samuele']
->>> for name in islice(reportlines, 3, None, 2):
-... print name.title()
-...
-Alex
-Laura
-Martin
-Walter
-Samuele
-
->>> from operator import itemgetter
->>> d = dict(a=1, b=2, c=1, d=2, e=1, f=2, g=3)
->>> di = sorted(sorted(d.iteritems()), key=itemgetter(1))
->>> for k, g in groupby(di, itemgetter(1)):
-... print k, map(itemgetter(0), g)
-...
-1 ['a', 'c', 'e']
-2 ['b', 'd', 'f']
-3 ['g']
-
-# Find runs of consecutive numbers using groupby. The key to the solution
-# is differencing with a range so that consecutive numbers all appear in
-# same group.
->>> data = [ 1, 4,5,6, 10, 15,16,17,18, 22, 25,26,27,28]
->>> for k, g in groupby(enumerate(data), lambda t:t[0]-t[1]):
-... print map(operator.itemgetter(1), g)
-...
-[1]
-[4, 5, 6]
-[10]
-[15, 16, 17, 18]
-[22]
-[25, 26, 27, 28]
-
->>> def take(n, iterable):
-... "Return first n items of the iterable as a list"
-... return list(islice(iterable, n))
-
->>> def enumerate(iterable, start=0):
-... return izip(count(start), iterable)
-
->>> def tabulate(function, start=0):
-... "Return function(0), function(1), ..."
-... return imap(function, count(start))
-
->>> def nth(iterable, n, default=None):
-... "Returns the nth item or a default value"
-... return next(islice(iterable, n, None), default)
-
->>> def quantify(iterable, pred=bool):
-... "Count how many times the predicate is true"
-... return sum(imap(pred, iterable))
-
->>> def padnone(iterable):
-... "Returns the sequence elements and then returns None indefinitely"
-... return chain(iterable, repeat(None))
-
->>> def ncycles(iterable, n):
-... "Returns the sequence elements n times"
-... return chain(*repeat(iterable, n))
-
->>> def dotproduct(vec1, vec2):
-... return sum(imap(operator.mul, vec1, vec2))
-
->>> def flatten(listOfLists):
-... return list(chain.from_iterable(listOfLists))
-
->>> def repeatfunc(func, times=None, *args):
-... "Repeat calls to func with specified arguments."
-... " Example: repeatfunc(random.random)"
-... if times is None:
-... return starmap(func, repeat(args))
-... else:
-... return starmap(func, repeat(args, times))
-
->>> def pairwise(iterable):
-... "s -> (s0,s1), (s1,s2), (s2, s3), ..."
-... a, b = tee(iterable)
-... for elem in b:
-... break
-... return izip(a, b)
-
->>> def grouper(n, iterable, fillvalue=None):
-... "grouper(3, 'ABCDEFG', 'x') --> ABC DEF Gxx"
-... args = [iter(iterable)] * n
-... return izip_longest(fillvalue=fillvalue, *args)
-
->>> def roundrobin(*iterables):
-... "roundrobin('ABC', 'D', 'EF') --> A D E B F C"
-... # Recipe credited to George Sakkis
-... pending = len(iterables)
-... nexts = cycle(iter(it).next for it in iterables)
-... while pending:
-... try:
-... for next in nexts:
-... yield next()
-... except StopIteration:
-... pending -= 1
-... nexts = cycle(islice(nexts, pending))
-
->>> def powerset(iterable):
-... "powerset([1,2,3]) --> () (1,) (2,) (3,) (1,2) (1,3) (2,3) (1,2,3)"
-... s = list(iterable)
-... return chain.from_iterable(combinations(s, r) for r in range(len(s)+1))
-
->>> def unique_everseen(iterable, key=None):
-... "List unique elements, preserving order. Remember all elements ever seen."
-... # unique_everseen('AAAABBBCCDAABBB') --> A B C D
-... # unique_everseen('ABBCcAD', str.lower) --> A B C D
-... seen = set()
-... seen_add = seen.add
-... if key is None:
-... for element in iterable:
-... if element not in seen:
-... seen_add(element)
-... yield element
-... else:
-... for element in iterable:
-... k = key(element)
-... if k not in seen:
-... seen_add(k)
-... yield element
-
->>> def unique_justseen(iterable, key=None):
-... "List unique elements, preserving order. Remember only the element just seen."
-... # unique_justseen('AAAABBBCCDAABBB') --> A B C D A B
-... # unique_justseen('ABBCcAD', str.lower) --> A B C A D
-... return imap(next, imap(itemgetter(1), groupby(iterable, key)))
-
-This is not part of the examples but it tests to make sure the definitions
-perform as purported.
-
->>> take(10, count())
-[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
-
->>> list(enumerate('abc'))
-[(0, 'a'), (1, 'b'), (2, 'c')]
-
->>> list(islice(tabulate(lambda x: 2*x), 4))
-[0, 2, 4, 6]
-
->>> nth('abcde', 3)
-'d'
-
->>> nth('abcde', 9) is None
-True
-
->>> quantify(xrange(99), lambda x: x%2==0)
-50
-
->>> a = [[1, 2, 3], [4, 5, 6]]
->>> flatten(a)
-[1, 2, 3, 4, 5, 6]
-
->>> list(repeatfunc(pow, 5, 2, 3))
-[8, 8, 8, 8, 8]
-
->>> import random
->>> take(5, imap(int, repeatfunc(random.random)))
-[0, 0, 0, 0, 0]
-
->>> list(pairwise('abcd'))
-[('a', 'b'), ('b', 'c'), ('c', 'd')]
-
->>> list(pairwise([]))
-[]
-
->>> list(pairwise('a'))
-[]
-
->>> list(islice(padnone('abc'), 0, 6))
-['a', 'b', 'c', None, None, None]
-
->>> list(ncycles('abc', 3))
-['a', 'b', 'c', 'a', 'b', 'c', 'a', 'b', 'c']
-
->>> dotproduct([1,2,3], [4,5,6])
-32
-
->>> list(grouper(3, 'abcdefg', 'x'))
-[('a', 'b', 'c'), ('d', 'e', 'f'), ('g', 'x', 'x')]
-
->>> list(roundrobin('abc', 'd', 'ef'))
-['a', 'd', 'e', 'b', 'f', 'c']
-
->>> list(powerset([1,2,3]))
-[(), (1,), (2,), (3,), (1, 2), (1, 3), (2, 3), (1, 2, 3)]
-
->>> all(len(list(powerset(range(n)))) == 2**n for n in range(18))
-True
-
->>> list(powerset('abcde')) == sorted(sorted(set(powerset('abcde'))), key=len)
-True
-
->>> list(unique_everseen('AAAABBBCCDAABBB'))
-['A', 'B', 'C', 'D']
-
->>> list(unique_everseen('ABBCcAD', str.lower))
-['A', 'B', 'C', 'D']
-
->>> list(unique_justseen('AAAABBBCCDAABBB'))
-['A', 'B', 'C', 'D', 'A', 'B']
-
->>> list(unique_justseen('ABBCcAD', str.lower))
-['A', 'B', 'C', 'A', 'D']
-
-"""
-
-__test__ = {'libreftest' : libreftest}
-
-def test_main(verbose=None):
- test_classes = (TestBasicOps, TestVariousIteratorArgs, TestGC,
- RegressionTests, LengthTransparency,
- SubclassWithKwargsTest, TestExamples)
- test_support.run_unittest(*test_classes)
-
- # verify reference counting
- if verbose and hasattr(sys, "gettotalrefcount"):
- import gc
- counts = [None] * 5
- for i in xrange(len(counts)):
- test_support.run_unittest(*test_classes)
- gc.collect()
- counts[i] = sys.gettotalrefcount()
- print counts
-
- # doctest the examples in the library reference
- test_support.run_doctest(sys.modules[__name__], verbose)
-
-if __name__ == "__main__":
- test_main(verbose=True)
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-21 16:23:46 +0000