| 1 | import unittest
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| 2 | from test import test_support
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| 3 | from itertools import *
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| 4 | from weakref import proxy
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| 5 | from decimal import Decimal
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| 6 | from fractions import Fraction
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| 7 | import sys
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| 8 | import operator
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| 9 | import random
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| 10 | import copy
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| 11 | import pickle
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| 12 | from functools import reduce
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| 13 | maxsize = test_support.MAX_Py_ssize_t
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| 14 | minsize = -maxsize-1
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| 15 |
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| 16 | def onearg(x):
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| 17 | 'Test function of one argument'
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| 18 | return 2*x
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| 19 |
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| 20 | def errfunc(*args):
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| 21 | 'Test function that raises an error'
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| 22 | raise ValueError
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| 23 |
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| 24 | def gen3():
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| 25 | 'Non-restartable source sequence'
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| 26 | for i in (0, 1, 2):
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| 27 | yield i
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| 28 |
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| 29 | def isEven(x):
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| 30 | 'Test predicate'
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| 31 | return x%2==0
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| 32 |
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| 33 | def isOdd(x):
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| 34 | 'Test predicate'
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| 35 | return x%2==1
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| 36 |
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| 37 | class StopNow:
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| 38 | 'Class emulating an empty iterable.'
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| 39 | def __iter__(self):
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| 40 | return self
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| 41 | def next(self):
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| 42 | raise StopIteration
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| 43 |
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| 44 | def take(n, seq):
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| 45 | 'Convenience function for partially consuming a long of infinite iterable'
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| 46 | return list(islice(seq, n))
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| 47 |
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| 48 | def prod(iterable):
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| 49 | return reduce(operator.mul, iterable, 1)
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| 50 |
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| 51 | def fact(n):
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| 52 | 'Factorial'
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| 53 | return prod(range(1, n+1))
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| 54 |
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| 55 | class TestBasicOps(unittest.TestCase):
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| 56 | def test_chain(self):
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| 57 |
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| 58 | def chain2(*iterables):
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| 59 | 'Pure python version in the docs'
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| 60 | for it in iterables:
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| 61 | for element in it:
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| 62 | yield element
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| 63 |
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| 64 | for c in (chain, chain2):
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| 65 | self.assertEqual(list(c('abc', 'def')), list('abcdef'))
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| 66 | self.assertEqual(list(c('abc')), list('abc'))
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| 67 | self.assertEqual(list(c('')), [])
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| 68 | self.assertEqual(take(4, c('abc', 'def')), list('abcd'))
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| 69 | self.assertRaises(TypeError, list,c(2, 3))
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| 70 |
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| 71 | def test_chain_from_iterable(self):
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| 72 | self.assertEqual(list(chain.from_iterable(['abc', 'def'])), list('abcdef'))
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| 73 | self.assertEqual(list(chain.from_iterable(['abc'])), list('abc'))
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| 74 | self.assertEqual(list(chain.from_iterable([''])), [])
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| 75 | self.assertEqual(take(4, chain.from_iterable(['abc', 'def'])), list('abcd'))
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| 76 | self.assertRaises(TypeError, list, chain.from_iterable([2, 3]))
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| 77 |
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| 78 | def test_combinations(self):
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| 79 | self.assertRaises(TypeError, combinations, 'abc') # missing r argument
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| 80 | self.assertRaises(TypeError, combinations, 'abc', 2, 1) # too many arguments
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| 81 | self.assertRaises(TypeError, combinations, None) # pool is not iterable
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| 82 | self.assertRaises(ValueError, combinations, 'abc', -2) # r is negative
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| 83 | self.assertEqual(list(combinations('abc', 32)), []) # r > n
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| 84 | self.assertEqual(list(combinations(range(4), 3)),
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| 85 | [(0,1,2), (0,1,3), (0,2,3), (1,2,3)])
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| 86 |
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| 87 | def combinations1(iterable, r):
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| 88 | 'Pure python version shown in the docs'
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| 89 | pool = tuple(iterable)
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| 90 | n = len(pool)
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| 91 | if r > n:
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| 92 | return
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| 93 | indices = range(r)
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| 94 | yield tuple(pool[i] for i in indices)
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| 95 | while 1:
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| 96 | for i in reversed(range(r)):
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| 97 | if indices[i] != i + n - r:
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| 98 | break
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| 99 | else:
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| 100 | return
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| 101 | indices[i] += 1
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| 102 | for j in range(i+1, r):
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| 103 | indices[j] = indices[j-1] + 1
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| 104 | yield tuple(pool[i] for i in indices)
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| 105 |
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| 106 | def combinations2(iterable, r):
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| 107 | 'Pure python version shown in the docs'
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| 108 | pool = tuple(iterable)
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| 109 | n = len(pool)
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| 110 | for indices in permutations(range(n), r):
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| 111 | if sorted(indices) == list(indices):
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| 112 | yield tuple(pool[i] for i in indices)
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| 113 |
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| 114 | def combinations3(iterable, r):
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| 115 | 'Pure python version from cwr()'
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| 116 | pool = tuple(iterable)
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| 117 | n = len(pool)
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| 118 | for indices in combinations_with_replacement(range(n), r):
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| 119 | if len(set(indices)) == r:
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| 120 | yield tuple(pool[i] for i in indices)
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| 121 |
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| 122 | for n in range(7):
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| 123 | values = [5*x-12 for x in range(n)]
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| 124 | for r in range(n+2):
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| 125 | result = list(combinations(values, r))
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| 126 | self.assertEqual(len(result), 0 if r>n else fact(n) // fact(r) // fact(n-r)) # right number of combs
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| 127 | self.assertEqual(len(result), len(set(result))) # no repeats
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| 128 | self.assertEqual(result, sorted(result)) # lexicographic order
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| 129 | for c in result:
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| 130 | self.assertEqual(len(c), r) # r-length combinations
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| 131 | self.assertEqual(len(set(c)), r) # no duplicate elements
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| 132 | self.assertEqual(list(c), sorted(c)) # keep original ordering
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| 133 | self.assertTrue(all(e in values for e in c)) # elements taken from input iterable
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| 134 | self.assertEqual(list(c),
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| 135 | [e for e in values if e in c]) # comb is a subsequence of the input iterable
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| 136 | self.assertEqual(result, list(combinations1(values, r))) # matches first pure python version
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| 137 | self.assertEqual(result, list(combinations2(values, r))) # matches second pure python version
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| 138 | self.assertEqual(result, list(combinations3(values, r))) # matches second pure python version
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| 139 |
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| 140 | @test_support.impl_detail("tuple reuse is specific to CPython")
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| 141 | def test_combinations_tuple_reuse(self):
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| 142 | self.assertEqual(len(set(map(id, combinations('abcde', 3)))), 1)
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| 143 | self.assertNotEqual(len(set(map(id, list(combinations('abcde', 3))))), 1)
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| 144 |
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| 145 | def test_combinations_with_replacement(self):
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| 146 | cwr = combinations_with_replacement
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| 147 | self.assertRaises(TypeError, cwr, 'abc') # missing r argument
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| 148 | self.assertRaises(TypeError, cwr, 'abc', 2, 1) # too many arguments
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| 149 | self.assertRaises(TypeError, cwr, None) # pool is not iterable
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| 150 | self.assertRaises(ValueError, cwr, 'abc', -2) # r is negative
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| 151 | self.assertEqual(list(cwr('ABC', 2)),
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| 152 | [('A','A'), ('A','B'), ('A','C'), ('B','B'), ('B','C'), ('C','C')])
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| 153 |
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| 154 | def cwr1(iterable, r):
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| 155 | 'Pure python version shown in the docs'
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| 156 | # number items returned: (n+r-1)! / r! / (n-1)! when n>0
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| 157 | pool = tuple(iterable)
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| 158 | n = len(pool)
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| 159 | if not n and r:
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| 160 | return
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| 161 | indices = [0] * r
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| 162 | yield tuple(pool[i] for i in indices)
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| 163 | while 1:
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| 164 | for i in reversed(range(r)):
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| 165 | if indices[i] != n - 1:
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| 166 | break
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| 167 | else:
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| 168 | return
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| 169 | indices[i:] = [indices[i] + 1] * (r - i)
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| 170 | yield tuple(pool[i] for i in indices)
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| 171 |
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| 172 | def cwr2(iterable, r):
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| 173 | 'Pure python version shown in the docs'
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| 174 | pool = tuple(iterable)
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| 175 | n = len(pool)
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| 176 | for indices in product(range(n), repeat=r):
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| 177 | if sorted(indices) == list(indices):
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| 178 | yield tuple(pool[i] for i in indices)
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| 179 |
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| 180 | def numcombs(n, r):
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| 181 | if not n:
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| 182 | return 0 if r else 1
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| 183 | return fact(n+r-1) // fact(r) // fact(n-1)
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| 184 |
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| 185 | for n in range(7):
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| 186 | values = [5*x-12 for x in range(n)]
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| 187 | for r in range(n+2):
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| 188 | result = list(cwr(values, r))
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| 189 |
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| 190 | self.assertEqual(len(result), numcombs(n, r)) # right number of combs
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| 191 | self.assertEqual(len(result), len(set(result))) # no repeats
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| 192 | self.assertEqual(result, sorted(result)) # lexicographic order
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| 193 |
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| 194 | regular_combs = list(combinations(values, r)) # compare to combs without replacement
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| 195 | if n == 0 or r <= 1:
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| 196 | self.assertEqual(result, regular_combs) # cases that should be identical
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| 197 | else:
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| 198 | self.assertTrue(set(result) >= set(regular_combs)) # rest should be supersets of regular combs
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| 199 |
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| 200 | for c in result:
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| 201 | self.assertEqual(len(c), r) # r-length combinations
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| 202 | noruns = [k for k,v in groupby(c)] # combo without consecutive repeats
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| 203 | self.assertEqual(len(noruns), len(set(noruns))) # no repeats other than consecutive
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| 204 | self.assertEqual(list(c), sorted(c)) # keep original ordering
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| 205 | self.assertTrue(all(e in values for e in c)) # elements taken from input iterable
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| 206 | self.assertEqual(noruns,
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| 207 | [e for e in values if e in c]) # comb is a subsequence of the input iterable
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| 208 | self.assertEqual(result, list(cwr1(values, r))) # matches first pure python version
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| 209 | self.assertEqual(result, list(cwr2(values, r))) # matches second pure python version
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| 210 |
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| 211 | @test_support.impl_detail("tuple reuse is specific to CPython")
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| 212 | def test_combinations_with_replacement_tuple_reuse(self):
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| 213 | cwr = combinations_with_replacement
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| 214 | self.assertEqual(len(set(map(id, cwr('abcde', 3)))), 1)
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| 215 | self.assertNotEqual(len(set(map(id, list(cwr('abcde', 3))))), 1)
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| 216 |
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| 217 | def test_permutations(self):
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| 218 | self.assertRaises(TypeError, permutations) # too few arguments
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| 219 | self.assertRaises(TypeError, permutations, 'abc', 2, 1) # too many arguments
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| 220 | self.assertRaises(TypeError, permutations, None) # pool is not iterable
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| 221 | self.assertRaises(ValueError, permutations, 'abc', -2) # r is negative
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| 222 | self.assertEqual(list(permutations('abc', 32)), []) # r > n
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| 223 | self.assertRaises(TypeError, permutations, 'abc', 's') # r is not an int or None
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| 224 | self.assertEqual(list(permutations(range(3), 2)),
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| 225 | [(0,1), (0,2), (1,0), (1,2), (2,0), (2,1)])
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| 226 |
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| 227 | def permutations1(iterable, r=None):
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| 228 | 'Pure python version shown in the docs'
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| 229 | pool = tuple(iterable)
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| 230 | n = len(pool)
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| 231 | r = n if r is None else r
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| 232 | if r > n:
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| 233 | return
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| 234 | indices = range(n)
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| 235 | cycles = range(n, n-r, -1)
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| 236 | yield tuple(pool[i] for i in indices[:r])
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| 237 | while n:
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| 238 | for i in reversed(range(r)):
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| 239 | cycles[i] -= 1
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| 240 | if cycles[i] == 0:
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| 241 | indices[i:] = indices[i+1:] + indices[i:i+1]
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| 242 | cycles[i] = n - i
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| 243 | else:
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| 244 | j = cycles[i]
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| 245 | indices[i], indices[-j] = indices[-j], indices[i]
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| 246 | yield tuple(pool[i] for i in indices[:r])
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| 247 | break
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| 248 | else:
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| 249 | return
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| 250 |
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| 251 | def permutations2(iterable, r=None):
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| 252 | 'Pure python version shown in the docs'
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| 253 | pool = tuple(iterable)
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| 254 | n = len(pool)
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| 255 | r = n if r is None else r
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| 256 | for indices in product(range(n), repeat=r):
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| 257 | if len(set(indices)) == r:
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| 258 | yield tuple(pool[i] for i in indices)
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| 259 |
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| 260 | for n in range(7):
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| 261 | values = [5*x-12 for x in range(n)]
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| 262 | for r in range(n+2):
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| 263 | result = list(permutations(values, r))
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| 264 | self.assertEqual(len(result), 0 if r>n else fact(n) // fact(n-r)) # right number of perms
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| 265 | self.assertEqual(len(result), len(set(result))) # no repeats
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| 266 | self.assertEqual(result, sorted(result)) # lexicographic order
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| 267 | for p in result:
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| 268 | self.assertEqual(len(p), r) # r-length permutations
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| 269 | self.assertEqual(len(set(p)), r) # no duplicate elements
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| 270 | self.assertTrue(all(e in values for e in p)) # elements taken from input iterable
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| 271 | self.assertEqual(result, list(permutations1(values, r))) # matches first pure python version
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| 272 | self.assertEqual(result, list(permutations2(values, r))) # matches second pure python version
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| 273 | if r == n:
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| 274 | self.assertEqual(result, list(permutations(values, None))) # test r as None
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| 275 | self.assertEqual(result, list(permutations(values))) # test default r
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| 276 |
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| 277 | @test_support.impl_detail("tuple resuse is CPython specific")
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| 278 | def test_permutations_tuple_reuse(self):
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| 279 | self.assertEqual(len(set(map(id, permutations('abcde', 3)))), 1)
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| 280 | self.assertNotEqual(len(set(map(id, list(permutations('abcde', 3))))), 1)
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| 281 |
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| 282 | def test_combinatorics(self):
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| 283 | # Test relationships between product(), permutations(),
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| 284 | # combinations() and combinations_with_replacement().
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| 285 |
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| 286 | for n in range(6):
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| 287 | s = 'ABCDEFG'[:n]
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| 288 | for r in range(8):
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| 289 | prod = list(product(s, repeat=r))
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| 290 | cwr = list(combinations_with_replacement(s, r))
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| 291 | perm = list(permutations(s, r))
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| 292 | comb = list(combinations(s, r))
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| 293 |
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| 294 | # Check size
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| 295 | self.assertEqual(len(prod), n**r)
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| 296 | self.assertEqual(len(cwr), (fact(n+r-1) // fact(r) // fact(n-1)) if n else (not r))
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| 297 | self.assertEqual(len(perm), 0 if r>n else fact(n) // fact(n-r))
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| 298 | self.assertEqual(len(comb), 0 if r>n else fact(n) // fact(r) // fact(n-r))
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| 299 |
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| 300 | # Check lexicographic order without repeated tuples
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| 301 | self.assertEqual(prod, sorted(set(prod)))
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| 302 | self.assertEqual(cwr, sorted(set(cwr)))
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| 303 | self.assertEqual(perm, sorted(set(perm)))
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| 304 | self.assertEqual(comb, sorted(set(comb)))
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| 305 |
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| 306 | # Check interrelationships
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| 307 | self.assertEqual(cwr, [t for t in prod if sorted(t)==list(t)]) # cwr: prods which are sorted
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| 308 | self.assertEqual(perm, [t for t in prod if len(set(t))==r]) # perm: prods with no dups
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| 309 | self.assertEqual(comb, [t for t in perm if sorted(t)==list(t)]) # comb: perms that are sorted
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| 310 | self.assertEqual(comb, [t for t in cwr if len(set(t))==r]) # comb: cwrs without dups
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| 311 | self.assertEqual(comb, filter(set(cwr).__contains__, perm)) # comb: perm that is a cwr
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| 312 | self.assertEqual(comb, filter(set(perm).__contains__, cwr)) # comb: cwr that is a perm
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| 313 | self.assertEqual(comb, sorted(set(cwr) & set(perm))) # comb: both a cwr and a perm
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| 314 |
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| 315 | def test_compress(self):
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| 316 | self.assertEqual(list(compress(data='ABCDEF', selectors=[1,0,1,0,1,1])), list('ACEF'))
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| 317 | self.assertEqual(list(compress('ABCDEF', [1,0,1,0,1,1])), list('ACEF'))
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| 318 | self.assertEqual(list(compress('ABCDEF', [0,0,0,0,0,0])), list(''))
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| 319 | self.assertEqual(list(compress('ABCDEF', [1,1,1,1,1,1])), list('ABCDEF'))
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| 320 | self.assertEqual(list(compress('ABCDEF', [1,0,1])), list('AC'))
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| 321 | self.assertEqual(list(compress('ABC', [0,1,1,1,1,1])), list('BC'))
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| 322 | n = 10000
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| 323 | data = chain.from_iterable(repeat(range(6), n))
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| 324 | selectors = chain.from_iterable(repeat((0, 1)))
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| 325 | self.assertEqual(list(compress(data, selectors)), [1,3,5] * n)
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| 326 | self.assertRaises(TypeError, compress, None, range(6)) # 1st arg not iterable
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| 327 | self.assertRaises(TypeError, compress, range(6), None) # 2nd arg not iterable
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| 328 | self.assertRaises(TypeError, compress, range(6)) # too few args
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| 329 | self.assertRaises(TypeError, compress, range(6), None) # too many args
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| 330 |
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| 331 | def test_count(self):
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| 332 | self.assertEqual(zip('abc',count()), [('a', 0), ('b', 1), ('c', 2)])
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| 333 | self.assertEqual(zip('abc',count(3)), [('a', 3), ('b', 4), ('c', 5)])
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| 334 | self.assertEqual(take(2, zip('abc',count(3))), [('a', 3), ('b', 4)])
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| 335 | self.assertEqual(take(2, zip('abc',count(-1))), [('a', -1), ('b', 0)])
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| 336 | self.assertEqual(take(2, zip('abc',count(-3))), [('a', -3), ('b', -2)])
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| 337 | self.assertRaises(TypeError, count, 2, 3, 4)
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| 338 | self.assertRaises(TypeError, count, 'a')
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| 339 | self.assertEqual(list(islice(count(maxsize-5), 10)), range(maxsize-5, maxsize+5))
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| 340 | self.assertEqual(list(islice(count(-maxsize-5), 10)), range(-maxsize-5, -maxsize+5))
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| 341 | c = count(3)
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| 342 | self.assertEqual(repr(c), 'count(3)')
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| 343 | c.next()
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| 344 | self.assertEqual(repr(c), 'count(4)')
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| 345 | c = count(-9)
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| 346 | self.assertEqual(repr(c), 'count(-9)')
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| 347 | c.next()
|
|---|
| 348 | self.assertEqual(repr(count(10.25)), 'count(10.25)')
|
|---|
| 349 | self.assertEqual(c.next(), -8)
|
|---|
| 350 | for i in (-sys.maxint-5, -sys.maxint+5 ,-10, -1, 0, 10, sys.maxint-5, sys.maxint+5):
|
|---|
| 351 | # Test repr (ignoring the L in longs)
|
|---|
| 352 | r1 = repr(count(i)).replace('L', '')
|
|---|
| 353 | r2 = 'count(%r)'.__mod__(i).replace('L', '')
|
|---|
| 354 | self.assertEqual(r1, r2)
|
|---|
| 355 |
|
|---|
| 356 | # check copy, deepcopy, pickle
|
|---|
| 357 | for value in -3, 3, sys.maxint-5, sys.maxint+5:
|
|---|
| 358 | c = count(value)
|
|---|
| 359 | self.assertEqual(next(copy.copy(c)), value)
|
|---|
| 360 | self.assertEqual(next(copy.deepcopy(c)), value)
|
|---|
| 361 | self.assertEqual(next(pickle.loads(pickle.dumps(c))), value)
|
|---|
| 362 |
|
|---|
| 363 | def test_count_with_stride(self):
|
|---|
| 364 | self.assertEqual(zip('abc',count(2,3)), [('a', 2), ('b', 5), ('c', 8)])
|
|---|
| 365 | self.assertEqual(zip('abc',count(start=2,step=3)),
|
|---|
| 366 | [('a', 2), ('b', 5), ('c', 8)])
|
|---|
| 367 | self.assertEqual(zip('abc',count(step=-1)),
|
|---|
| 368 | [('a', 0), ('b', -1), ('c', -2)])
|
|---|
| 369 | self.assertEqual(zip('abc',count(2,0)), [('a', 2), ('b', 2), ('c', 2)])
|
|---|
| 370 | self.assertEqual(zip('abc',count(2,1)), [('a', 2), ('b', 3), ('c', 4)])
|
|---|
| 371 | self.assertEqual(take(20, count(maxsize-15, 3)), take(20, range(maxsize-15, maxsize+100, 3)))
|
|---|
| 372 | self.assertEqual(take(20, count(-maxsize-15, 3)), take(20, range(-maxsize-15,-maxsize+100, 3)))
|
|---|
| 373 | self.assertEqual(take(3, count(2, 3.25-4j)), [2, 5.25-4j, 8.5-8j])
|
|---|
| 374 | self.assertEqual(take(3, count(Decimal('1.1'), Decimal('.1'))),
|
|---|
| 375 | [Decimal('1.1'), Decimal('1.2'), Decimal('1.3')])
|
|---|
| 376 | self.assertEqual(take(3, count(Fraction(2,3), Fraction(1,7))),
|
|---|
| 377 | [Fraction(2,3), Fraction(17,21), Fraction(20,21)])
|
|---|
| 378 | self.assertEqual(repr(take(3, count(10, 2.5))), repr([10, 12.5, 15.0]))
|
|---|
| 379 | c = count(3, 5)
|
|---|
| 380 | self.assertEqual(repr(c), 'count(3, 5)')
|
|---|
| 381 | c.next()
|
|---|
| 382 | self.assertEqual(repr(c), 'count(8, 5)')
|
|---|
| 383 | c = count(-9, 0)
|
|---|
| 384 | self.assertEqual(repr(c), 'count(-9, 0)')
|
|---|
| 385 | c.next()
|
|---|
| 386 | self.assertEqual(repr(c), 'count(-9, 0)')
|
|---|
| 387 | c = count(-9, -3)
|
|---|
| 388 | self.assertEqual(repr(c), 'count(-9, -3)')
|
|---|
| 389 | c.next()
|
|---|
| 390 | self.assertEqual(repr(c), 'count(-12, -3)')
|
|---|
| 391 | self.assertEqual(repr(c), 'count(-12, -3)')
|
|---|
| 392 | self.assertEqual(repr(count(10.5, 1.25)), 'count(10.5, 1.25)')
|
|---|
| 393 | self.assertEqual(repr(count(10.5, 1)), 'count(10.5)') # suppress step=1 when it's an int
|
|---|
| 394 | self.assertEqual(repr(count(10.5, 1.00)), 'count(10.5, 1.0)') # do show float values lilke 1.0
|
|---|
| 395 | for i in (-sys.maxint-5, -sys.maxint+5 ,-10, -1, 0, 10, sys.maxint-5, sys.maxint+5):
|
|---|
| 396 | for j in (-sys.maxint-5, -sys.maxint+5 ,-10, -1, 0, 1, 10, sys.maxint-5, sys.maxint+5):
|
|---|
| 397 | # Test repr (ignoring the L in longs)
|
|---|
| 398 | r1 = repr(count(i, j)).replace('L', '')
|
|---|
| 399 | if j == 1:
|
|---|
| 400 | r2 = ('count(%r)' % i).replace('L', '')
|
|---|
| 401 | else:
|
|---|
| 402 | r2 = ('count(%r, %r)' % (i, j)).replace('L', '')
|
|---|
| 403 | self.assertEqual(r1, r2)
|
|---|
| 404 |
|
|---|
| 405 | def test_cycle(self):
|
|---|
| 406 | self.assertEqual(take(10, cycle('abc')), list('abcabcabca'))
|
|---|
| 407 | self.assertEqual(list(cycle('')), [])
|
|---|
| 408 | self.assertRaises(TypeError, cycle)
|
|---|
| 409 | self.assertRaises(TypeError, cycle, 5)
|
|---|
| 410 | self.assertEqual(list(islice(cycle(gen3()),10)), [0,1,2,0,1,2,0,1,2,0])
|
|---|
| 411 |
|
|---|
| 412 | def test_groupby(self):
|
|---|
| 413 | # Check whether it accepts arguments correctly
|
|---|
| 414 | self.assertEqual([], list(groupby([])))
|
|---|
| 415 | self.assertEqual([], list(groupby([], key=id)))
|
|---|
| 416 | self.assertRaises(TypeError, list, groupby('abc', []))
|
|---|
| 417 | self.assertRaises(TypeError, groupby, None)
|
|---|
| 418 | self.assertRaises(TypeError, groupby, 'abc', lambda x:x, 10)
|
|---|
| 419 |
|
|---|
| 420 | # Check normal input
|
|---|
| 421 | s = [(0, 10, 20), (0, 11,21), (0,12,21), (1,13,21), (1,14,22),
|
|---|
| 422 | (2,15,22), (3,16,23), (3,17,23)]
|
|---|
| 423 | dup = []
|
|---|
| 424 | for k, g in groupby(s, lambda r:r[0]):
|
|---|
| 425 | for elem in g:
|
|---|
| 426 | self.assertEqual(k, elem[0])
|
|---|
| 427 | dup.append(elem)
|
|---|
| 428 | self.assertEqual(s, dup)
|
|---|
| 429 |
|
|---|
| 430 | # Check nested case
|
|---|
| 431 | dup = []
|
|---|
| 432 | for k, g in groupby(s, lambda r:r[0]):
|
|---|
| 433 | for ik, ig in groupby(g, lambda r:r[2]):
|
|---|
| 434 | for elem in ig:
|
|---|
| 435 | self.assertEqual(k, elem[0])
|
|---|
| 436 | self.assertEqual(ik, elem[2])
|
|---|
| 437 | dup.append(elem)
|
|---|
| 438 | self.assertEqual(s, dup)
|
|---|
| 439 |
|
|---|
| 440 | # Check case where inner iterator is not used
|
|---|
| 441 | keys = [k for k, g in groupby(s, lambda r:r[0])]
|
|---|
| 442 | expectedkeys = set([r[0] for r in s])
|
|---|
| 443 | self.assertEqual(set(keys), expectedkeys)
|
|---|
| 444 | self.assertEqual(len(keys), len(expectedkeys))
|
|---|
| 445 |
|
|---|
| 446 | # Exercise pipes and filters style
|
|---|
| 447 | s = 'abracadabra'
|
|---|
| 448 | # sort s | uniq
|
|---|
| 449 | r = [k for k, g in groupby(sorted(s))]
|
|---|
| 450 | self.assertEqual(r, ['a', 'b', 'c', 'd', 'r'])
|
|---|
| 451 | # sort s | uniq -d
|
|---|
| 452 | r = [k for k, g in groupby(sorted(s)) if list(islice(g,1,2))]
|
|---|
| 453 | self.assertEqual(r, ['a', 'b', 'r'])
|
|---|
| 454 | # sort s | uniq -c
|
|---|
| 455 | r = [(len(list(g)), k) for k, g in groupby(sorted(s))]
|
|---|
| 456 | self.assertEqual(r, [(5, 'a'), (2, 'b'), (1, 'c'), (1, 'd'), (2, 'r')])
|
|---|
| 457 | # sort s | uniq -c | sort -rn | head -3
|
|---|
| 458 | r = sorted([(len(list(g)) , k) for k, g in groupby(sorted(s))], reverse=True)[:3]
|
|---|
| 459 | self.assertEqual(r, [(5, 'a'), (2, 'r'), (2, 'b')])
|
|---|
| 460 |
|
|---|
| 461 | # iter.next failure
|
|---|
| 462 | class ExpectedError(Exception):
|
|---|
| 463 | pass
|
|---|
| 464 | def delayed_raise(n=0):
|
|---|
| 465 | for i in range(n):
|
|---|
| 466 | yield 'yo'
|
|---|
| 467 | raise ExpectedError
|
|---|
| 468 | def gulp(iterable, keyp=None, func=list):
|
|---|
| 469 | return [func(g) for k, g in groupby(iterable, keyp)]
|
|---|
| 470 |
|
|---|
| 471 | # iter.next failure on outer object
|
|---|
| 472 | self.assertRaises(ExpectedError, gulp, delayed_raise(0))
|
|---|
| 473 | # iter.next failure on inner object
|
|---|
| 474 | self.assertRaises(ExpectedError, gulp, delayed_raise(1))
|
|---|
| 475 |
|
|---|
| 476 | # __cmp__ failure
|
|---|
| 477 | class DummyCmp:
|
|---|
| 478 | def __cmp__(self, dst):
|
|---|
| 479 | raise ExpectedError
|
|---|
| 480 | s = [DummyCmp(), DummyCmp(), None]
|
|---|
| 481 |
|
|---|
| 482 | # __cmp__ failure on outer object
|
|---|
| 483 | self.assertRaises(ExpectedError, gulp, s, func=id)
|
|---|
| 484 | # __cmp__ failure on inner object
|
|---|
| 485 | self.assertRaises(ExpectedError, gulp, s)
|
|---|
| 486 |
|
|---|
| 487 | # keyfunc failure
|
|---|
| 488 | def keyfunc(obj):
|
|---|
| 489 | if keyfunc.skip > 0:
|
|---|
| 490 | keyfunc.skip -= 1
|
|---|
| 491 | return obj
|
|---|
| 492 | else:
|
|---|
| 493 | raise ExpectedError
|
|---|
| 494 |
|
|---|
| 495 | # keyfunc failure on outer object
|
|---|
| 496 | keyfunc.skip = 0
|
|---|
| 497 | self.assertRaises(ExpectedError, gulp, [None], keyfunc)
|
|---|
| 498 | keyfunc.skip = 1
|
|---|
| 499 | self.assertRaises(ExpectedError, gulp, [None, None], keyfunc)
|
|---|
| 500 |
|
|---|
| 501 | def test_ifilter(self):
|
|---|
| 502 | self.assertEqual(list(ifilter(isEven, range(6))), [0,2,4])
|
|---|
| 503 | self.assertEqual(list(ifilter(None, [0,1,0,2,0])), [1,2])
|
|---|
| 504 | self.assertEqual(list(ifilter(bool, [0,1,0,2,0])), [1,2])
|
|---|
| 505 | self.assertEqual(take(4, ifilter(isEven, count())), [0,2,4,6])
|
|---|
| 506 | self.assertRaises(TypeError, ifilter)
|
|---|
| 507 | self.assertRaises(TypeError, ifilter, lambda x:x)
|
|---|
| 508 | self.assertRaises(TypeError, ifilter, lambda x:x, range(6), 7)
|
|---|
| 509 | self.assertRaises(TypeError, ifilter, isEven, 3)
|
|---|
| 510 | self.assertRaises(TypeError, ifilter(range(6), range(6)).next)
|
|---|
| 511 |
|
|---|
| 512 | def test_ifilterfalse(self):
|
|---|
| 513 | self.assertEqual(list(ifilterfalse(isEven, range(6))), [1,3,5])
|
|---|
| 514 | self.assertEqual(list(ifilterfalse(None, [0,1,0,2,0])), [0,0,0])
|
|---|
| 515 | self.assertEqual(list(ifilterfalse(bool, [0,1,0,2,0])), [0,0,0])
|
|---|
| 516 | self.assertEqual(take(4, ifilterfalse(isEven, count())), [1,3,5,7])
|
|---|
| 517 | self.assertRaises(TypeError, ifilterfalse)
|
|---|
| 518 | self.assertRaises(TypeError, ifilterfalse, lambda x:x)
|
|---|
| 519 | self.assertRaises(TypeError, ifilterfalse, lambda x:x, range(6), 7)
|
|---|
| 520 | self.assertRaises(TypeError, ifilterfalse, isEven, 3)
|
|---|
| 521 | self.assertRaises(TypeError, ifilterfalse(range(6), range(6)).next)
|
|---|
| 522 |
|
|---|
| 523 | def test_izip(self):
|
|---|
| 524 | ans = [(x,y) for x, y in izip('abc',count())]
|
|---|
| 525 | self.assertEqual(ans, [('a', 0), ('b', 1), ('c', 2)])
|
|---|
| 526 | self.assertEqual(list(izip('abc', range(6))), zip('abc', range(6)))
|
|---|
| 527 | self.assertEqual(list(izip('abcdef', range(3))), zip('abcdef', range(3)))
|
|---|
| 528 | self.assertEqual(take(3,izip('abcdef', count())), zip('abcdef', range(3)))
|
|---|
| 529 | self.assertEqual(list(izip('abcdef')), zip('abcdef'))
|
|---|
| 530 | self.assertEqual(list(izip()), zip())
|
|---|
| 531 | self.assertRaises(TypeError, izip, 3)
|
|---|
| 532 | self.assertRaises(TypeError, izip, range(3), 3)
|
|---|
| 533 | self.assertEqual([tuple(list(pair)) for pair in izip('abc', 'def')],
|
|---|
| 534 | zip('abc', 'def'))
|
|---|
| 535 | self.assertEqual([pair for pair in izip('abc', 'def')],
|
|---|
| 536 | zip('abc', 'def'))
|
|---|
| 537 |
|
|---|
| 538 | @test_support.impl_detail("tuple reuse is specific to CPython")
|
|---|
| 539 | def test_izip_tuple_resuse(self):
|
|---|
| 540 | ids = map(id, izip('abc', 'def'))
|
|---|
| 541 | self.assertEqual(min(ids), max(ids))
|
|---|
| 542 | ids = map(id, list(izip('abc', 'def')))
|
|---|
| 543 | self.assertEqual(len(dict.fromkeys(ids)), len(ids))
|
|---|
| 544 |
|
|---|
| 545 | def test_iziplongest(self):
|
|---|
| 546 | for args in [
|
|---|
| 547 | ['abc', range(6)],
|
|---|
| 548 | [range(6), 'abc'],
|
|---|
| 549 | [range(1000), range(2000,2100), range(3000,3050)],
|
|---|
| 550 | [range(1000), range(0), range(3000,3050), range(1200), range(1500)],
|
|---|
| 551 | [range(1000), range(0), range(3000,3050), range(1200), range(1500), range(0)],
|
|---|
| 552 | ]:
|
|---|
| 553 | # target = map(None, *args) <- this raises a py3k warning
|
|---|
| 554 | # this is the replacement:
|
|---|
| 555 | target = [tuple([arg[i] if i < len(arg) else None for arg in args])
|
|---|
| 556 | for i in range(max(map(len, args)))]
|
|---|
| 557 | self.assertEqual(list(izip_longest(*args)), target)
|
|---|
| 558 | self.assertEqual(list(izip_longest(*args, **{})), target)
|
|---|
| 559 | target = [tuple((e is None and 'X' or e) for e in t) for t in target] # Replace None fills with 'X'
|
|---|
| 560 | self.assertEqual(list(izip_longest(*args, **dict(fillvalue='X'))), target)
|
|---|
| 561 |
|
|---|
| 562 | self.assertEqual(take(3,izip_longest('abcdef', count())), zip('abcdef', range(3))) # take 3 from infinite input
|
|---|
| 563 |
|
|---|
| 564 | self.assertEqual(list(izip_longest()), zip())
|
|---|
| 565 | self.assertEqual(list(izip_longest([])), zip([]))
|
|---|
| 566 | self.assertEqual(list(izip_longest('abcdef')), zip('abcdef'))
|
|---|
| 567 |
|
|---|
| 568 | self.assertEqual(list(izip_longest('abc', 'defg', **{})),
|
|---|
| 569 | zip(list('abc') + [None], 'defg')) # empty keyword dict
|
|---|
| 570 | self.assertRaises(TypeError, izip_longest, 3)
|
|---|
| 571 | self.assertRaises(TypeError, izip_longest, range(3), 3)
|
|---|
| 572 |
|
|---|
| 573 | for stmt in [
|
|---|
| 574 | "izip_longest('abc', fv=1)",
|
|---|
| 575 | "izip_longest('abc', fillvalue=1, bogus_keyword=None)",
|
|---|
| 576 | ]:
|
|---|
| 577 | try:
|
|---|
| 578 | eval(stmt, globals(), locals())
|
|---|
| 579 | except TypeError:
|
|---|
| 580 | pass
|
|---|
| 581 | else:
|
|---|
| 582 | self.fail('Did not raise Type in: ' + stmt)
|
|---|
| 583 |
|
|---|
| 584 | self.assertEqual([tuple(list(pair)) for pair in izip_longest('abc', 'def')],
|
|---|
| 585 | zip('abc', 'def'))
|
|---|
| 586 | self.assertEqual([pair for pair in izip_longest('abc', 'def')],
|
|---|
| 587 | zip('abc', 'def'))
|
|---|
| 588 |
|
|---|
| 589 | @test_support.impl_detail("tuple reuse is specific to CPython")
|
|---|
| 590 | def test_izip_longest_tuple_reuse(self):
|
|---|
| 591 | ids = map(id, izip_longest('abc', 'def'))
|
|---|
| 592 | self.assertEqual(min(ids), max(ids))
|
|---|
| 593 | ids = map(id, list(izip_longest('abc', 'def')))
|
|---|
| 594 | self.assertEqual(len(dict.fromkeys(ids)), len(ids))
|
|---|
| 595 |
|
|---|
| 596 | def test_bug_7244(self):
|
|---|
| 597 |
|
|---|
| 598 | class Repeater(object):
|
|---|
| 599 | # this class is similar to itertools.repeat
|
|---|
| 600 | def __init__(self, o, t, e):
|
|---|
| 601 | self.o = o
|
|---|
| 602 | self.t = int(t)
|
|---|
| 603 | self.e = e
|
|---|
| 604 | def __iter__(self): # its iterator is itself
|
|---|
| 605 | return self
|
|---|
| 606 | def next(self):
|
|---|
| 607 | if self.t > 0:
|
|---|
| 608 | self.t -= 1
|
|---|
| 609 | return self.o
|
|---|
| 610 | else:
|
|---|
| 611 | raise self.e
|
|---|
| 612 |
|
|---|
| 613 | # Formerly this code in would fail in debug mode
|
|---|
| 614 | # with Undetected Error and Stop Iteration
|
|---|
| 615 | r1 = Repeater(1, 3, StopIteration)
|
|---|
| 616 | r2 = Repeater(2, 4, StopIteration)
|
|---|
| 617 | def run(r1, r2):
|
|---|
| 618 | result = []
|
|---|
| 619 | for i, j in izip_longest(r1, r2, fillvalue=0):
|
|---|
| 620 | with test_support.captured_output('stdout'):
|
|---|
| 621 | print (i, j)
|
|---|
| 622 | result.append((i, j))
|
|---|
| 623 | return result
|
|---|
| 624 | self.assertEqual(run(r1, r2), [(1,2), (1,2), (1,2), (0,2)])
|
|---|
| 625 |
|
|---|
| 626 | # Formerly, the RuntimeError would be lost
|
|---|
| 627 | # and StopIteration would stop as expected
|
|---|
| 628 | r1 = Repeater(1, 3, RuntimeError)
|
|---|
| 629 | r2 = Repeater(2, 4, StopIteration)
|
|---|
| 630 | it = izip_longest(r1, r2, fillvalue=0)
|
|---|
| 631 | self.assertEqual(next(it), (1, 2))
|
|---|
| 632 | self.assertEqual(next(it), (1, 2))
|
|---|
| 633 | self.assertEqual(next(it), (1, 2))
|
|---|
| 634 | self.assertRaises(RuntimeError, next, it)
|
|---|
| 635 |
|
|---|
| 636 | def test_product(self):
|
|---|
| 637 | for args, result in [
|
|---|
| 638 | ([], [()]), # zero iterables
|
|---|
| 639 | (['ab'], [('a',), ('b',)]), # one iterable
|
|---|
| 640 | ([range(2), range(3)], [(0,0), (0,1), (0,2), (1,0), (1,1), (1,2)]), # two iterables
|
|---|
| 641 | ([range(0), range(2), range(3)], []), # first iterable with zero length
|
|---|
| 642 | ([range(2), range(0), range(3)], []), # middle iterable with zero length
|
|---|
| 643 | ([range(2), range(3), range(0)], []), # last iterable with zero length
|
|---|
| 644 | ]:
|
|---|
| 645 | self.assertEqual(list(product(*args)), result)
|
|---|
| 646 | for r in range(4):
|
|---|
| 647 | self.assertEqual(list(product(*(args*r))),
|
|---|
| 648 | list(product(*args, **dict(repeat=r))))
|
|---|
| 649 | self.assertEqual(len(list(product(*[range(7)]*6))), 7**6)
|
|---|
| 650 | self.assertRaises(TypeError, product, range(6), None)
|
|---|
| 651 |
|
|---|
| 652 | def product1(*args, **kwds):
|
|---|
| 653 | pools = map(tuple, args) * kwds.get('repeat', 1)
|
|---|
| 654 | n = len(pools)
|
|---|
| 655 | if n == 0:
|
|---|
| 656 | yield ()
|
|---|
| 657 | return
|
|---|
| 658 | if any(len(pool) == 0 for pool in pools):
|
|---|
| 659 | return
|
|---|
| 660 | indices = [0] * n
|
|---|
| 661 | yield tuple(pool[i] for pool, i in zip(pools, indices))
|
|---|
| 662 | while 1:
|
|---|
| 663 | for i in reversed(range(n)): # right to left
|
|---|
| 664 | if indices[i] == len(pools[i]) - 1:
|
|---|
| 665 | continue
|
|---|
| 666 | indices[i] += 1
|
|---|
| 667 | for j in range(i+1, n):
|
|---|
| 668 | indices[j] = 0
|
|---|
| 669 | yield tuple(pool[i] for pool, i in zip(pools, indices))
|
|---|
| 670 | break
|
|---|
| 671 | else:
|
|---|
| 672 | return
|
|---|
| 673 |
|
|---|
| 674 | def product2(*args, **kwds):
|
|---|
| 675 | 'Pure python version used in docs'
|
|---|
| 676 | pools = map(tuple, args) * kwds.get('repeat', 1)
|
|---|
| 677 | result = [[]]
|
|---|
| 678 | for pool in pools:
|
|---|
| 679 | result = [x+[y] for x in result for y in pool]
|
|---|
| 680 | for prod in result:
|
|---|
| 681 | yield tuple(prod)
|
|---|
| 682 |
|
|---|
| 683 | argtypes = ['', 'abc', '', xrange(0), xrange(4), dict(a=1, b=2, c=3),
|
|---|
| 684 | set('abcdefg'), range(11), tuple(range(13))]
|
|---|
| 685 | for i in range(100):
|
|---|
| 686 | args = [random.choice(argtypes) for j in range(random.randrange(5))]
|
|---|
| 687 | expected_len = prod(map(len, args))
|
|---|
| 688 | self.assertEqual(len(list(product(*args))), expected_len)
|
|---|
| 689 | self.assertEqual(list(product(*args)), list(product1(*args)))
|
|---|
| 690 | self.assertEqual(list(product(*args)), list(product2(*args)))
|
|---|
| 691 | args = map(iter, args)
|
|---|
| 692 | self.assertEqual(len(list(product(*args))), expected_len)
|
|---|
| 693 |
|
|---|
| 694 | @test_support.impl_detail("tuple reuse is specific to CPython")
|
|---|
| 695 | def test_product_tuple_reuse(self):
|
|---|
| 696 | self.assertEqual(len(set(map(id, product('abc', 'def')))), 1)
|
|---|
| 697 | self.assertNotEqual(len(set(map(id, list(product('abc', 'def'))))), 1)
|
|---|
| 698 |
|
|---|
| 699 | def test_repeat(self):
|
|---|
| 700 | self.assertEqual(list(repeat(object='a', times=3)), ['a', 'a', 'a'])
|
|---|
| 701 | self.assertEqual(zip(xrange(3),repeat('a')),
|
|---|
| 702 | [(0, 'a'), (1, 'a'), (2, 'a')])
|
|---|
| 703 | self.assertEqual(list(repeat('a', 3)), ['a', 'a', 'a'])
|
|---|
| 704 | self.assertEqual(take(3, repeat('a')), ['a', 'a', 'a'])
|
|---|
| 705 | self.assertEqual(list(repeat('a', 0)), [])
|
|---|
| 706 | self.assertEqual(list(repeat('a', -3)), [])
|
|---|
| 707 | self.assertRaises(TypeError, repeat)
|
|---|
| 708 | self.assertRaises(TypeError, repeat, None, 3, 4)
|
|---|
| 709 | self.assertRaises(TypeError, repeat, None, 'a')
|
|---|
| 710 | r = repeat(1+0j)
|
|---|
| 711 | self.assertEqual(repr(r), 'repeat((1+0j))')
|
|---|
| 712 | r = repeat(1+0j, 5)
|
|---|
| 713 | self.assertEqual(repr(r), 'repeat((1+0j), 5)')
|
|---|
| 714 | list(r)
|
|---|
| 715 | self.assertEqual(repr(r), 'repeat((1+0j), 0)')
|
|---|
| 716 |
|
|---|
| 717 | def test_imap(self):
|
|---|
| 718 | self.assertEqual(list(imap(operator.pow, range(3), range(1,7))),
|
|---|
| 719 | [0**1, 1**2, 2**3])
|
|---|
| 720 | self.assertEqual(list(imap(None, 'abc', range(5))),
|
|---|
| 721 | [('a',0),('b',1),('c',2)])
|
|---|
| 722 | self.assertEqual(list(imap(None, 'abc', count())),
|
|---|
| 723 | [('a',0),('b',1),('c',2)])
|
|---|
| 724 | self.assertEqual(take(2,imap(None, 'abc', count())),
|
|---|
| 725 | [('a',0),('b',1)])
|
|---|
| 726 | self.assertEqual(list(imap(operator.pow, [])), [])
|
|---|
| 727 | self.assertRaises(TypeError, imap)
|
|---|
| 728 | self.assertRaises(TypeError, imap, operator.neg)
|
|---|
| 729 | self.assertRaises(TypeError, imap(10, range(5)).next)
|
|---|
| 730 | self.assertRaises(ValueError, imap(errfunc, [4], [5]).next)
|
|---|
| 731 | self.assertRaises(TypeError, imap(onearg, [4], [5]).next)
|
|---|
| 732 |
|
|---|
| 733 | def test_starmap(self):
|
|---|
| 734 | self.assertEqual(list(starmap(operator.pow, zip(range(3), range(1,7)))),
|
|---|
| 735 | [0**1, 1**2, 2**3])
|
|---|
| 736 | self.assertEqual(take(3, starmap(operator.pow, izip(count(), count(1)))),
|
|---|
| 737 | [0**1, 1**2, 2**3])
|
|---|
| 738 | self.assertEqual(list(starmap(operator.pow, [])), [])
|
|---|
| 739 | self.assertEqual(list(starmap(operator.pow, [iter([4,5])])), [4**5])
|
|---|
| 740 | self.assertRaises(TypeError, list, starmap(operator.pow, [None]))
|
|---|
| 741 | self.assertRaises(TypeError, starmap)
|
|---|
| 742 | self.assertRaises(TypeError, starmap, operator.pow, [(4,5)], 'extra')
|
|---|
| 743 | self.assertRaises(TypeError, starmap(10, [(4,5)]).next)
|
|---|
| 744 | self.assertRaises(ValueError, starmap(errfunc, [(4,5)]).next)
|
|---|
| 745 | self.assertRaises(TypeError, starmap(onearg, [(4,5)]).next)
|
|---|
| 746 |
|
|---|
| 747 | def test_islice(self):
|
|---|
| 748 | for args in [ # islice(args) should agree with range(args)
|
|---|
| 749 | (10, 20, 3),
|
|---|
| 750 | (10, 3, 20),
|
|---|
| 751 | (10, 20),
|
|---|
| 752 | (10, 3),
|
|---|
| 753 | (20,)
|
|---|
| 754 | ]:
|
|---|
| 755 | self.assertEqual(list(islice(xrange(100), *args)), range(*args))
|
|---|
| 756 |
|
|---|
| 757 | for args, tgtargs in [ # Stop when seqn is exhausted
|
|---|
| 758 | ((10, 110, 3), ((10, 100, 3))),
|
|---|
| 759 | ((10, 110), ((10, 100))),
|
|---|
| 760 | ((110,), (100,))
|
|---|
| 761 | ]:
|
|---|
| 762 | self.assertEqual(list(islice(xrange(100), *args)), range(*tgtargs))
|
|---|
| 763 |
|
|---|
| 764 | # Test stop=None
|
|---|
| 765 | self.assertEqual(list(islice(xrange(10), None)), range(10))
|
|---|
| 766 | self.assertEqual(list(islice(xrange(10), None, None)), range(10))
|
|---|
| 767 | self.assertEqual(list(islice(xrange(10), None, None, None)), range(10))
|
|---|
| 768 | self.assertEqual(list(islice(xrange(10), 2, None)), range(2, 10))
|
|---|
| 769 | self.assertEqual(list(islice(xrange(10), 1, None, 2)), range(1, 10, 2))
|
|---|
| 770 |
|
|---|
| 771 | # Test number of items consumed SF #1171417
|
|---|
| 772 | it = iter(range(10))
|
|---|
| 773 | self.assertEqual(list(islice(it, 3)), range(3))
|
|---|
| 774 | self.assertEqual(list(it), range(3, 10))
|
|---|
| 775 |
|
|---|
| 776 | # Test invalid arguments
|
|---|
| 777 | self.assertRaises(TypeError, islice, xrange(10))
|
|---|
| 778 | self.assertRaises(TypeError, islice, xrange(10), 1, 2, 3, 4)
|
|---|
| 779 | self.assertRaises(ValueError, islice, xrange(10), -5, 10, 1)
|
|---|
| 780 | self.assertRaises(ValueError, islice, xrange(10), 1, -5, -1)
|
|---|
| 781 | self.assertRaises(ValueError, islice, xrange(10), 1, 10, -1)
|
|---|
| 782 | self.assertRaises(ValueError, islice, xrange(10), 1, 10, 0)
|
|---|
| 783 | self.assertRaises(ValueError, islice, xrange(10), 'a')
|
|---|
| 784 | self.assertRaises(ValueError, islice, xrange(10), 'a', 1)
|
|---|
| 785 | self.assertRaises(ValueError, islice, xrange(10), 1, 'a')
|
|---|
| 786 | self.assertRaises(ValueError, islice, xrange(10), 'a', 1, 1)
|
|---|
| 787 | self.assertRaises(ValueError, islice, xrange(10), 1, 'a', 1)
|
|---|
| 788 | self.assertEqual(len(list(islice(count(), 1, 10, maxsize))), 1)
|
|---|
| 789 |
|
|---|
| 790 | # Issue #10323: Less islice in a predictable state
|
|---|
| 791 | c = count()
|
|---|
| 792 | self.assertEqual(list(islice(c, 1, 3, 50)), [1])
|
|---|
| 793 | self.assertEqual(next(c), 3)
|
|---|
| 794 |
|
|---|
| 795 | def test_takewhile(self):
|
|---|
| 796 | data = [1, 3, 5, 20, 2, 4, 6, 8]
|
|---|
| 797 | underten = lambda x: x<10
|
|---|
| 798 | self.assertEqual(list(takewhile(underten, data)), [1, 3, 5])
|
|---|
| 799 | self.assertEqual(list(takewhile(underten, [])), [])
|
|---|
| 800 | self.assertRaises(TypeError, takewhile)
|
|---|
| 801 | self.assertRaises(TypeError, takewhile, operator.pow)
|
|---|
| 802 | self.assertRaises(TypeError, takewhile, operator.pow, [(4,5)], 'extra')
|
|---|
| 803 | self.assertRaises(TypeError, takewhile(10, [(4,5)]).next)
|
|---|
| 804 | self.assertRaises(ValueError, takewhile(errfunc, [(4,5)]).next)
|
|---|
| 805 | t = takewhile(bool, [1, 1, 1, 0, 0, 0])
|
|---|
| 806 | self.assertEqual(list(t), [1, 1, 1])
|
|---|
| 807 | self.assertRaises(StopIteration, t.next)
|
|---|
| 808 |
|
|---|
| 809 | def test_dropwhile(self):
|
|---|
| 810 | data = [1, 3, 5, 20, 2, 4, 6, 8]
|
|---|
| 811 | underten = lambda x: x<10
|
|---|
| 812 | self.assertEqual(list(dropwhile(underten, data)), [20, 2, 4, 6, 8])
|
|---|
| 813 | self.assertEqual(list(dropwhile(underten, [])), [])
|
|---|
| 814 | self.assertRaises(TypeError, dropwhile)
|
|---|
| 815 | self.assertRaises(TypeError, dropwhile, operator.pow)
|
|---|
| 816 | self.assertRaises(TypeError, dropwhile, operator.pow, [(4,5)], 'extra')
|
|---|
| 817 | self.assertRaises(TypeError, dropwhile(10, [(4,5)]).next)
|
|---|
| 818 | self.assertRaises(ValueError, dropwhile(errfunc, [(4,5)]).next)
|
|---|
| 819 |
|
|---|
| 820 | def test_tee(self):
|
|---|
| 821 | n = 200
|
|---|
| 822 | def irange(n):
|
|---|
| 823 | for i in xrange(n):
|
|---|
| 824 | yield i
|
|---|
| 825 |
|
|---|
| 826 | a, b = tee([]) # test empty iterator
|
|---|
| 827 | self.assertEqual(list(a), [])
|
|---|
| 828 | self.assertEqual(list(b), [])
|
|---|
| 829 |
|
|---|
| 830 | a, b = tee(irange(n)) # test 100% interleaved
|
|---|
| 831 | self.assertEqual(zip(a,b), zip(range(n),range(n)))
|
|---|
| 832 |
|
|---|
| 833 | a, b = tee(irange(n)) # test 0% interleaved
|
|---|
| 834 | self.assertEqual(list(a), range(n))
|
|---|
| 835 | self.assertEqual(list(b), range(n))
|
|---|
| 836 |
|
|---|
| 837 | a, b = tee(irange(n)) # test dealloc of leading iterator
|
|---|
| 838 | for i in xrange(100):
|
|---|
| 839 | self.assertEqual(a.next(), i)
|
|---|
| 840 | del a
|
|---|
| 841 | self.assertEqual(list(b), range(n))
|
|---|
| 842 |
|
|---|
| 843 | a, b = tee(irange(n)) # test dealloc of trailing iterator
|
|---|
| 844 | for i in xrange(100):
|
|---|
| 845 | self.assertEqual(a.next(), i)
|
|---|
| 846 | del b
|
|---|
| 847 | self.assertEqual(list(a), range(100, n))
|
|---|
| 848 |
|
|---|
| 849 | for j in xrange(5): # test randomly interleaved
|
|---|
| 850 | order = [0]*n + [1]*n
|
|---|
| 851 | random.shuffle(order)
|
|---|
| 852 | lists = ([], [])
|
|---|
| 853 | its = tee(irange(n))
|
|---|
| 854 | for i in order:
|
|---|
| 855 | value = its[i].next()
|
|---|
| 856 | lists[i].append(value)
|
|---|
| 857 | self.assertEqual(lists[0], range(n))
|
|---|
| 858 | self.assertEqual(lists[1], range(n))
|
|---|
| 859 |
|
|---|
| 860 | # test argument format checking
|
|---|
| 861 | self.assertRaises(TypeError, tee)
|
|---|
| 862 | self.assertRaises(TypeError, tee, 3)
|
|---|
| 863 | self.assertRaises(TypeError, tee, [1,2], 'x')
|
|---|
| 864 | self.assertRaises(TypeError, tee, [1,2], 3, 'x')
|
|---|
| 865 |
|
|---|
| 866 | # tee object should be instantiable
|
|---|
| 867 | a, b = tee('abc')
|
|---|
| 868 | c = type(a)('def')
|
|---|
| 869 | self.assertEqual(list(c), list('def'))
|
|---|
| 870 |
|
|---|
| 871 | # test long-lagged and multi-way split
|
|---|
| 872 | a, b, c = tee(xrange(2000), 3)
|
|---|
| 873 | for i in xrange(100):
|
|---|
| 874 | self.assertEqual(a.next(), i)
|
|---|
| 875 | self.assertEqual(list(b), range(2000))
|
|---|
| 876 | self.assertEqual([c.next(), c.next()], range(2))
|
|---|
| 877 | self.assertEqual(list(a), range(100,2000))
|
|---|
| 878 | self.assertEqual(list(c), range(2,2000))
|
|---|
| 879 |
|
|---|
| 880 | # test values of n
|
|---|
| 881 | self.assertRaises(TypeError, tee, 'abc', 'invalid')
|
|---|
| 882 | self.assertRaises(ValueError, tee, [], -1)
|
|---|
| 883 | for n in xrange(5):
|
|---|
| 884 | result = tee('abc', n)
|
|---|
| 885 | self.assertEqual(type(result), tuple)
|
|---|
| 886 | self.assertEqual(len(result), n)
|
|---|
| 887 | self.assertEqual(map(list, result), [list('abc')]*n)
|
|---|
| 888 |
|
|---|
| 889 | # tee pass-through to copyable iterator
|
|---|
| 890 | a, b = tee('abc')
|
|---|
| 891 | c, d = tee(a)
|
|---|
| 892 | self.assertTrue(a is c)
|
|---|
| 893 |
|
|---|
| 894 | # test tee_new
|
|---|
| 895 | t1, t2 = tee('abc')
|
|---|
| 896 | tnew = type(t1)
|
|---|
| 897 | self.assertRaises(TypeError, tnew)
|
|---|
| 898 | self.assertRaises(TypeError, tnew, 10)
|
|---|
| 899 | t3 = tnew(t1)
|
|---|
| 900 | self.assertTrue(list(t1) == list(t2) == list(t3) == list('abc'))
|
|---|
| 901 |
|
|---|
| 902 | # test that tee objects are weak referencable
|
|---|
| 903 | a, b = tee(xrange(10))
|
|---|
| 904 | p = proxy(a)
|
|---|
| 905 | self.assertEqual(getattr(p, '__class__'), type(b))
|
|---|
| 906 | del a
|
|---|
| 907 | self.assertRaises(ReferenceError, getattr, p, '__class__')
|
|---|
| 908 |
|
|---|
| 909 | # Issue 13454: Crash when deleting backward iterator from tee()
|
|---|
| 910 | def test_tee_del_backward(self):
|
|---|
| 911 | forward, backward = tee(repeat(None, 20000000))
|
|---|
| 912 | any(forward) # exhaust the iterator
|
|---|
| 913 | del backward
|
|---|
| 914 |
|
|---|
| 915 | def test_StopIteration(self):
|
|---|
| 916 | self.assertRaises(StopIteration, izip().next)
|
|---|
| 917 |
|
|---|
| 918 | for f in (chain, cycle, izip, groupby):
|
|---|
| 919 | self.assertRaises(StopIteration, f([]).next)
|
|---|
| 920 | self.assertRaises(StopIteration, f(StopNow()).next)
|
|---|
| 921 |
|
|---|
| 922 | self.assertRaises(StopIteration, islice([], None).next)
|
|---|
| 923 | self.assertRaises(StopIteration, islice(StopNow(), None).next)
|
|---|
| 924 |
|
|---|
| 925 | p, q = tee([])
|
|---|
| 926 | self.assertRaises(StopIteration, p.next)
|
|---|
| 927 | self.assertRaises(StopIteration, q.next)
|
|---|
| 928 | p, q = tee(StopNow())
|
|---|
| 929 | self.assertRaises(StopIteration, p.next)
|
|---|
| 930 | self.assertRaises(StopIteration, q.next)
|
|---|
| 931 |
|
|---|
| 932 | self.assertRaises(StopIteration, repeat(None, 0).next)
|
|---|
| 933 |
|
|---|
| 934 | for f in (ifilter, ifilterfalse, imap, takewhile, dropwhile, starmap):
|
|---|
| 935 | self.assertRaises(StopIteration, f(lambda x:x, []).next)
|
|---|
| 936 | self.assertRaises(StopIteration, f(lambda x:x, StopNow()).next)
|
|---|
| 937 |
|
|---|
| 938 | class TestExamples(unittest.TestCase):
|
|---|
| 939 |
|
|---|
| 940 | def test_chain(self):
|
|---|
| 941 | self.assertEqual(''.join(chain('ABC', 'DEF')), 'ABCDEF')
|
|---|
| 942 |
|
|---|
| 943 | def test_chain_from_iterable(self):
|
|---|
| 944 | self.assertEqual(''.join(chain.from_iterable(['ABC', 'DEF'])), 'ABCDEF')
|
|---|
| 945 |
|
|---|
| 946 | def test_combinations(self):
|
|---|
| 947 | self.assertEqual(list(combinations('ABCD', 2)),
|
|---|
| 948 | [('A','B'), ('A','C'), ('A','D'), ('B','C'), ('B','D'), ('C','D')])
|
|---|
| 949 | self.assertEqual(list(combinations(range(4), 3)),
|
|---|
| 950 | [(0,1,2), (0,1,3), (0,2,3), (1,2,3)])
|
|---|
| 951 |
|
|---|
| 952 | def test_combinations_with_replacement(self):
|
|---|
| 953 | self.assertEqual(list(combinations_with_replacement('ABC', 2)),
|
|---|
| 954 | [('A','A'), ('A','B'), ('A','C'), ('B','B'), ('B','C'), ('C','C')])
|
|---|
| 955 |
|
|---|
| 956 | def test_compress(self):
|
|---|
| 957 | self.assertEqual(list(compress('ABCDEF', [1,0,1,0,1,1])), list('ACEF'))
|
|---|
| 958 |
|
|---|
| 959 | def test_count(self):
|
|---|
| 960 | self.assertEqual(list(islice(count(10), 5)), [10, 11, 12, 13, 14])
|
|---|
| 961 |
|
|---|
| 962 | def test_cycle(self):
|
|---|
| 963 | self.assertEqual(list(islice(cycle('ABCD'), 12)), list('ABCDABCDABCD'))
|
|---|
| 964 |
|
|---|
| 965 | def test_dropwhile(self):
|
|---|
| 966 | self.assertEqual(list(dropwhile(lambda x: x<5, [1,4,6,4,1])), [6,4,1])
|
|---|
| 967 |
|
|---|
| 968 | def test_groupby(self):
|
|---|
| 969 | self.assertEqual([k for k, g in groupby('AAAABBBCCDAABBB')],
|
|---|
| 970 | list('ABCDAB'))
|
|---|
| 971 | self.assertEqual([(list(g)) for k, g in groupby('AAAABBBCCD')],
|
|---|
| 972 | [list('AAAA'), list('BBB'), list('CC'), list('D')])
|
|---|
| 973 |
|
|---|
| 974 | def test_ifilter(self):
|
|---|
| 975 | self.assertEqual(list(ifilter(lambda x: x%2, range(10))), [1,3,5,7,9])
|
|---|
| 976 |
|
|---|
| 977 | def test_ifilterfalse(self):
|
|---|
| 978 | self.assertEqual(list(ifilterfalse(lambda x: x%2, range(10))), [0,2,4,6,8])
|
|---|
| 979 |
|
|---|
| 980 | def test_imap(self):
|
|---|
| 981 | self.assertEqual(list(imap(pow, (2,3,10), (5,2,3))), [32, 9, 1000])
|
|---|
| 982 |
|
|---|
| 983 | def test_islice(self):
|
|---|
| 984 | self.assertEqual(list(islice('ABCDEFG', 2)), list('AB'))
|
|---|
| 985 | self.assertEqual(list(islice('ABCDEFG', 2, 4)), list('CD'))
|
|---|
| 986 | self.assertEqual(list(islice('ABCDEFG', 2, None)), list('CDEFG'))
|
|---|
| 987 | self.assertEqual(list(islice('ABCDEFG', 0, None, 2)), list('ACEG'))
|
|---|
| 988 |
|
|---|
| 989 | def test_izip(self):
|
|---|
| 990 | self.assertEqual(list(izip('ABCD', 'xy')), [('A', 'x'), ('B', 'y')])
|
|---|
| 991 |
|
|---|
| 992 | def test_izip_longest(self):
|
|---|
| 993 | self.assertEqual(list(izip_longest('ABCD', 'xy', fillvalue='-')),
|
|---|
| 994 | [('A', 'x'), ('B', 'y'), ('C', '-'), ('D', '-')])
|
|---|
| 995 |
|
|---|
| 996 | def test_permutations(self):
|
|---|
| 997 | self.assertEqual(list(permutations('ABCD', 2)),
|
|---|
| 998 | map(tuple, 'AB AC AD BA BC BD CA CB CD DA DB DC'.split()))
|
|---|
| 999 | self.assertEqual(list(permutations(range(3))),
|
|---|
| 1000 | [(0,1,2), (0,2,1), (1,0,2), (1,2,0), (2,0,1), (2,1,0)])
|
|---|
| 1001 |
|
|---|
| 1002 | def test_product(self):
|
|---|
| 1003 | self.assertEqual(list(product('ABCD', 'xy')),
|
|---|
| 1004 | map(tuple, 'Ax Ay Bx By Cx Cy Dx Dy'.split()))
|
|---|
| 1005 | self.assertEqual(list(product(range(2), repeat=3)),
|
|---|
| 1006 | [(0,0,0), (0,0,1), (0,1,0), (0,1,1),
|
|---|
| 1007 | (1,0,0), (1,0,1), (1,1,0), (1,1,1)])
|
|---|
| 1008 |
|
|---|
| 1009 | def test_repeat(self):
|
|---|
| 1010 | self.assertEqual(list(repeat(10, 3)), [10, 10, 10])
|
|---|
| 1011 |
|
|---|
| 1012 | def test_stapmap(self):
|
|---|
| 1013 | self.assertEqual(list(starmap(pow, [(2,5), (3,2), (10,3)])),
|
|---|
| 1014 | [32, 9, 1000])
|
|---|
| 1015 |
|
|---|
| 1016 | def test_takewhile(self):
|
|---|
| 1017 | self.assertEqual(list(takewhile(lambda x: x<5, [1,4,6,4,1])), [1,4])
|
|---|
| 1018 |
|
|---|
| 1019 |
|
|---|
| 1020 | class TestGC(unittest.TestCase):
|
|---|
| 1021 |
|
|---|
| 1022 | def makecycle(self, iterator, container):
|
|---|
| 1023 | container.append(iterator)
|
|---|
| 1024 | iterator.next()
|
|---|
| 1025 | del container, iterator
|
|---|
| 1026 |
|
|---|
| 1027 | def test_chain(self):
|
|---|
| 1028 | a = []
|
|---|
| 1029 | self.makecycle(chain(a), a)
|
|---|
| 1030 |
|
|---|
| 1031 | def test_chain_from_iterable(self):
|
|---|
| 1032 | a = []
|
|---|
| 1033 | self.makecycle(chain.from_iterable([a]), a)
|
|---|
| 1034 |
|
|---|
| 1035 | def test_combinations(self):
|
|---|
| 1036 | a = []
|
|---|
| 1037 | self.makecycle(combinations([1,2,a,3], 3), a)
|
|---|
| 1038 |
|
|---|
| 1039 | def test_combinations_with_replacement(self):
|
|---|
| 1040 | a = []
|
|---|
| 1041 | self.makecycle(combinations_with_replacement([1,2,a,3], 3), a)
|
|---|
| 1042 |
|
|---|
| 1043 | def test_compress(self):
|
|---|
| 1044 | a = []
|
|---|
| 1045 | self.makecycle(compress('ABCDEF', [1,0,1,0,1,0]), a)
|
|---|
| 1046 |
|
|---|
| 1047 | def test_count(self):
|
|---|
| 1048 | a = []
|
|---|
| 1049 | Int = type('Int', (int,), dict(x=a))
|
|---|
| 1050 | self.makecycle(count(Int(0), Int(1)), a)
|
|---|
| 1051 |
|
|---|
| 1052 | def test_cycle(self):
|
|---|
| 1053 | a = []
|
|---|
| 1054 | self.makecycle(cycle([a]*2), a)
|
|---|
| 1055 |
|
|---|
| 1056 | def test_dropwhile(self):
|
|---|
| 1057 | a = []
|
|---|
| 1058 | self.makecycle(dropwhile(bool, [0, a, a]), a)
|
|---|
| 1059 |
|
|---|
| 1060 | def test_groupby(self):
|
|---|
| 1061 | a = []
|
|---|
| 1062 | self.makecycle(groupby([a]*2, lambda x:x), a)
|
|---|
| 1063 |
|
|---|
| 1064 | def test_issue2246(self):
|
|---|
| 1065 | # Issue 2246 -- the _grouper iterator was not included in GC
|
|---|
| 1066 | n = 10
|
|---|
| 1067 | keyfunc = lambda x: x
|
|---|
| 1068 | for i, j in groupby(xrange(n), key=keyfunc):
|
|---|
| 1069 | keyfunc.__dict__.setdefault('x',[]).append(j)
|
|---|
| 1070 |
|
|---|
| 1071 | def test_ifilter(self):
|
|---|
| 1072 | a = []
|
|---|
| 1073 | self.makecycle(ifilter(lambda x:True, [a]*2), a)
|
|---|
| 1074 |
|
|---|
| 1075 | def test_ifilterfalse(self):
|
|---|
| 1076 | a = []
|
|---|
| 1077 | self.makecycle(ifilterfalse(lambda x:False, a), a)
|
|---|
| 1078 |
|
|---|
| 1079 | def test_izip(self):
|
|---|
| 1080 | a = []
|
|---|
| 1081 | self.makecycle(izip([a]*2, [a]*3), a)
|
|---|
| 1082 |
|
|---|
| 1083 | def test_izip_longest(self):
|
|---|
| 1084 | a = []
|
|---|
| 1085 | self.makecycle(izip_longest([a]*2, [a]*3), a)
|
|---|
| 1086 | b = [a, None]
|
|---|
| 1087 | self.makecycle(izip_longest([a]*2, [a]*3, fillvalue=b), a)
|
|---|
| 1088 |
|
|---|
| 1089 | def test_imap(self):
|
|---|
| 1090 | a = []
|
|---|
| 1091 | self.makecycle(imap(lambda x:x, [a]*2), a)
|
|---|
| 1092 |
|
|---|
| 1093 | def test_islice(self):
|
|---|
| 1094 | a = []
|
|---|
| 1095 | self.makecycle(islice([a]*2, None), a)
|
|---|
| 1096 |
|
|---|
| 1097 | def test_permutations(self):
|
|---|
| 1098 | a = []
|
|---|
| 1099 | self.makecycle(permutations([1,2,a,3], 3), a)
|
|---|
| 1100 |
|
|---|
| 1101 | def test_product(self):
|
|---|
| 1102 | a = []
|
|---|
| 1103 | self.makecycle(product([1,2,a,3], repeat=3), a)
|
|---|
| 1104 |
|
|---|
| 1105 | def test_repeat(self):
|
|---|
| 1106 | a = []
|
|---|
| 1107 | self.makecycle(repeat(a), a)
|
|---|
| 1108 |
|
|---|
| 1109 | def test_starmap(self):
|
|---|
| 1110 | a = []
|
|---|
| 1111 | self.makecycle(starmap(lambda *t: t, [(a,a)]*2), a)
|
|---|
| 1112 |
|
|---|
| 1113 | def test_takewhile(self):
|
|---|
| 1114 | a = []
|
|---|
| 1115 | self.makecycle(takewhile(bool, [1, 0, a, a]), a)
|
|---|
| 1116 |
|
|---|
| 1117 | def R(seqn):
|
|---|
| 1118 | 'Regular generator'
|
|---|
| 1119 | for i in seqn:
|
|---|
| 1120 | yield i
|
|---|
| 1121 |
|
|---|
| 1122 | class G:
|
|---|
| 1123 | 'Sequence using __getitem__'
|
|---|
| 1124 | def __init__(self, seqn):
|
|---|
| 1125 | self.seqn = seqn
|
|---|
| 1126 | def __getitem__(self, i):
|
|---|
| 1127 | return self.seqn[i]
|
|---|
| 1128 |
|
|---|
| 1129 | class I:
|
|---|
| 1130 | 'Sequence using iterator protocol'
|
|---|
| 1131 | def __init__(self, seqn):
|
|---|
| 1132 | self.seqn = seqn
|
|---|
| 1133 | self.i = 0
|
|---|
| 1134 | def __iter__(self):
|
|---|
| 1135 | return self
|
|---|
| 1136 | def next(self):
|
|---|
| 1137 | if self.i >= len(self.seqn): raise StopIteration
|
|---|
| 1138 | v = self.seqn[self.i]
|
|---|
| 1139 | self.i += 1
|
|---|
| 1140 | return v
|
|---|
| 1141 |
|
|---|
| 1142 | class Ig:
|
|---|
| 1143 | 'Sequence using iterator protocol defined with a generator'
|
|---|
| 1144 | def __init__(self, seqn):
|
|---|
| 1145 | self.seqn = seqn
|
|---|
| 1146 | self.i = 0
|
|---|
| 1147 | def __iter__(self):
|
|---|
| 1148 | for val in self.seqn:
|
|---|
| 1149 | yield val
|
|---|
| 1150 |
|
|---|
| 1151 | class X:
|
|---|
| 1152 | 'Missing __getitem__ and __iter__'
|
|---|
| 1153 | def __init__(self, seqn):
|
|---|
| 1154 | self.seqn = seqn
|
|---|
| 1155 | self.i = 0
|
|---|
| 1156 | def next(self):
|
|---|
| 1157 | if self.i >= len(self.seqn): raise StopIteration
|
|---|
| 1158 | v = self.seqn[self.i]
|
|---|
| 1159 | self.i += 1
|
|---|
| 1160 | return v
|
|---|
| 1161 |
|
|---|
| 1162 | class N:
|
|---|
| 1163 | 'Iterator missing next()'
|
|---|
| 1164 | def __init__(self, seqn):
|
|---|
| 1165 | self.seqn = seqn
|
|---|
| 1166 | self.i = 0
|
|---|
| 1167 | def __iter__(self):
|
|---|
| 1168 | return self
|
|---|
| 1169 |
|
|---|
| 1170 | class E:
|
|---|
| 1171 | 'Test propagation of exceptions'
|
|---|
| 1172 | def __init__(self, seqn):
|
|---|
| 1173 | self.seqn = seqn
|
|---|
| 1174 | self.i = 0
|
|---|
| 1175 | def __iter__(self):
|
|---|
| 1176 | return self
|
|---|
| 1177 | def next(self):
|
|---|
| 1178 | 3 // 0
|
|---|
| 1179 |
|
|---|
| 1180 | class S:
|
|---|
| 1181 | 'Test immediate stop'
|
|---|
| 1182 | def __init__(self, seqn):
|
|---|
| 1183 | pass
|
|---|
| 1184 | def __iter__(self):
|
|---|
| 1185 | return self
|
|---|
| 1186 | def next(self):
|
|---|
| 1187 | raise StopIteration
|
|---|
| 1188 |
|
|---|
| 1189 | def L(seqn):
|
|---|
| 1190 | 'Test multiple tiers of iterators'
|
|---|
| 1191 | return chain(imap(lambda x:x, R(Ig(G(seqn)))))
|
|---|
| 1192 |
|
|---|
| 1193 |
|
|---|
| 1194 | class TestVariousIteratorArgs(unittest.TestCase):
|
|---|
| 1195 |
|
|---|
| 1196 | def test_chain(self):
|
|---|
| 1197 | for s in ("123", "", range(1000), ('do', 1.2), xrange(2000,2200,5)):
|
|---|
| 1198 | for g in (G, I, Ig, S, L, R):
|
|---|
| 1199 | self.assertEqual(list(chain(g(s))), list(g(s)))
|
|---|
| 1200 | self.assertEqual(list(chain(g(s), g(s))), list(g(s))+list(g(s)))
|
|---|
| 1201 | self.assertRaises(TypeError, list, chain(X(s)))
|
|---|
| 1202 | self.assertRaises(TypeError, list, chain(N(s)))
|
|---|
| 1203 | self.assertRaises(ZeroDivisionError, list, chain(E(s)))
|
|---|
| 1204 |
|
|---|
| 1205 | def test_compress(self):
|
|---|
| 1206 | for s in ("123", "", range(1000), ('do', 1.2), xrange(2000,2200,5)):
|
|---|
| 1207 | n = len(s)
|
|---|
| 1208 | for g in (G, I, Ig, S, L, R):
|
|---|
| 1209 | self.assertEqual(list(compress(g(s), repeat(1))), list(g(s)))
|
|---|
| 1210 | self.assertRaises(TypeError, compress, X(s), repeat(1))
|
|---|
| 1211 | self.assertRaises(TypeError, list, compress(N(s), repeat(1)))
|
|---|
| 1212 | self.assertRaises(ZeroDivisionError, list, compress(E(s), repeat(1)))
|
|---|
| 1213 |
|
|---|
| 1214 | def test_product(self):
|
|---|
| 1215 | for s in ("123", "", range(1000), ('do', 1.2), xrange(2000,2200,5)):
|
|---|
| 1216 | self.assertRaises(TypeError, product, X(s))
|
|---|
| 1217 | self.assertRaises(TypeError, product, N(s))
|
|---|
| 1218 | self.assertRaises(ZeroDivisionError, product, E(s))
|
|---|
| 1219 |
|
|---|
| 1220 | def test_cycle(self):
|
|---|
| 1221 | for s in ("123", "", range(1000), ('do', 1.2), xrange(2000,2200,5)):
|
|---|
| 1222 | for g in (G, I, Ig, S, L, R):
|
|---|
| 1223 | tgtlen = len(s) * 3
|
|---|
| 1224 | expected = list(g(s))*3
|
|---|
| 1225 | actual = list(islice(cycle(g(s)), tgtlen))
|
|---|
| 1226 | self.assertEqual(actual, expected)
|
|---|
| 1227 | self.assertRaises(TypeError, cycle, X(s))
|
|---|
| 1228 | self.assertRaises(TypeError, list, cycle(N(s)))
|
|---|
| 1229 | self.assertRaises(ZeroDivisionError, list, cycle(E(s)))
|
|---|
| 1230 |
|
|---|
| 1231 | def test_groupby(self):
|
|---|
| 1232 | for s in (range(10), range(0), range(1000), (7,11), xrange(2000,2200,5)):
|
|---|
| 1233 | for g in (G, I, Ig, S, L, R):
|
|---|
| 1234 | self.assertEqual([k for k, sb in groupby(g(s))], list(g(s)))
|
|---|
| 1235 | self.assertRaises(TypeError, groupby, X(s))
|
|---|
| 1236 | self.assertRaises(TypeError, list, groupby(N(s)))
|
|---|
| 1237 | self.assertRaises(ZeroDivisionError, list, groupby(E(s)))
|
|---|
| 1238 |
|
|---|
| 1239 | def test_ifilter(self):
|
|---|
| 1240 | for s in (range(10), range(0), range(1000), (7,11), xrange(2000,2200,5)):
|
|---|
| 1241 | for g in (G, I, Ig, S, L, R):
|
|---|
| 1242 | self.assertEqual(list(ifilter(isEven, g(s))), filter(isEven, g(s)))
|
|---|
| 1243 | self.assertRaises(TypeError, ifilter, isEven, X(s))
|
|---|
| 1244 | self.assertRaises(TypeError, list, ifilter(isEven, N(s)))
|
|---|
| 1245 | self.assertRaises(ZeroDivisionError, list, ifilter(isEven, E(s)))
|
|---|
| 1246 |
|
|---|
| 1247 | def test_ifilterfalse(self):
|
|---|
| 1248 | for s in (range(10), range(0), range(1000), (7,11), xrange(2000,2200,5)):
|
|---|
| 1249 | for g in (G, I, Ig, S, L, R):
|
|---|
| 1250 | self.assertEqual(list(ifilterfalse(isEven, g(s))), filter(isOdd, g(s)))
|
|---|
| 1251 | self.assertRaises(TypeError, ifilterfalse, isEven, X(s))
|
|---|
| 1252 | self.assertRaises(TypeError, list, ifilterfalse(isEven, N(s)))
|
|---|
| 1253 | self.assertRaises(ZeroDivisionError, list, ifilterfalse(isEven, E(s)))
|
|---|
| 1254 |
|
|---|
| 1255 | def test_izip(self):
|
|---|
| 1256 | for s in ("123", "", range(1000), ('do', 1.2), xrange(2000,2200,5)):
|
|---|
| 1257 | for g in (G, I, Ig, S, L, R):
|
|---|
| 1258 | self.assertEqual(list(izip(g(s))), zip(g(s)))
|
|---|
| 1259 | self.assertEqual(list(izip(g(s), g(s))), zip(g(s), g(s)))
|
|---|
| 1260 | self.assertRaises(TypeError, izip, X(s))
|
|---|
| 1261 | self.assertRaises(TypeError, list, izip(N(s)))
|
|---|
| 1262 | self.assertRaises(ZeroDivisionError, list, izip(E(s)))
|
|---|
| 1263 |
|
|---|
| 1264 | def test_iziplongest(self):
|
|---|
| 1265 | for s in ("123", "", range(1000), ('do', 1.2), xrange(2000,2200,5)):
|
|---|
| 1266 | for g in (G, I, Ig, S, L, R):
|
|---|
| 1267 | self.assertEqual(list(izip_longest(g(s))), zip(g(s)))
|
|---|
| 1268 | self.assertEqual(list(izip_longest(g(s), g(s))), zip(g(s), g(s)))
|
|---|
| 1269 | self.assertRaises(TypeError, izip_longest, X(s))
|
|---|
| 1270 | self.assertRaises(TypeError, list, izip_longest(N(s)))
|
|---|
| 1271 | self.assertRaises(ZeroDivisionError, list, izip_longest(E(s)))
|
|---|
| 1272 |
|
|---|
| 1273 | def test_imap(self):
|
|---|
| 1274 | for s in (range(10), range(0), range(100), (7,11), xrange(20,50,5)):
|
|---|
| 1275 | for g in (G, I, Ig, S, L, R):
|
|---|
| 1276 | self.assertEqual(list(imap(onearg, g(s))), map(onearg, g(s)))
|
|---|
| 1277 | self.assertEqual(list(imap(operator.pow, g(s), g(s))), map(operator.pow, g(s), g(s)))
|
|---|
| 1278 | self.assertRaises(TypeError, imap, onearg, X(s))
|
|---|
| 1279 | self.assertRaises(TypeError, list, imap(onearg, N(s)))
|
|---|
| 1280 | self.assertRaises(ZeroDivisionError, list, imap(onearg, E(s)))
|
|---|
| 1281 |
|
|---|
| 1282 | def test_islice(self):
|
|---|
| 1283 | for s in ("12345", "", range(1000), ('do', 1.2), xrange(2000,2200,5)):
|
|---|
| 1284 | for g in (G, I, Ig, S, L, R):
|
|---|
| 1285 | self.assertEqual(list(islice(g(s),1,None,2)), list(g(s))[1::2])
|
|---|
| 1286 | self.assertRaises(TypeError, islice, X(s), 10)
|
|---|
| 1287 | self.assertRaises(TypeError, list, islice(N(s), 10))
|
|---|
| 1288 | self.assertRaises(ZeroDivisionError, list, islice(E(s), 10))
|
|---|
| 1289 |
|
|---|
| 1290 | def test_starmap(self):
|
|---|
| 1291 | for s in (range(10), range(0), range(100), (7,11), xrange(20,50,5)):
|
|---|
| 1292 | for g in (G, I, Ig, S, L, R):
|
|---|
| 1293 | ss = zip(s, s)
|
|---|
| 1294 | self.assertEqual(list(starmap(operator.pow, g(ss))), map(operator.pow, g(s), g(s)))
|
|---|
| 1295 | self.assertRaises(TypeError, starmap, operator.pow, X(ss))
|
|---|
| 1296 | self.assertRaises(TypeError, list, starmap(operator.pow, N(ss)))
|
|---|
| 1297 | self.assertRaises(ZeroDivisionError, list, starmap(operator.pow, E(ss)))
|
|---|
| 1298 |
|
|---|
| 1299 | def test_takewhile(self):
|
|---|
| 1300 | for s in (range(10), range(0), range(1000), (7,11), xrange(2000,2200,5)):
|
|---|
| 1301 | for g in (G, I, Ig, S, L, R):
|
|---|
| 1302 | tgt = []
|
|---|
| 1303 | for elem in g(s):
|
|---|
| 1304 | if not isEven(elem): break
|
|---|
| 1305 | tgt.append(elem)
|
|---|
| 1306 | self.assertEqual(list(takewhile(isEven, g(s))), tgt)
|
|---|
| 1307 | self.assertRaises(TypeError, takewhile, isEven, X(s))
|
|---|
| 1308 | self.assertRaises(TypeError, list, takewhile(isEven, N(s)))
|
|---|
| 1309 | self.assertRaises(ZeroDivisionError, list, takewhile(isEven, E(s)))
|
|---|
| 1310 |
|
|---|
| 1311 | def test_dropwhile(self):
|
|---|
| 1312 | for s in (range(10), range(0), range(1000), (7,11), xrange(2000,2200,5)):
|
|---|
| 1313 | for g in (G, I, Ig, S, L, R):
|
|---|
| 1314 | tgt = []
|
|---|
| 1315 | for elem in g(s):
|
|---|
| 1316 | if not tgt and isOdd(elem): continue
|
|---|
| 1317 | tgt.append(elem)
|
|---|
| 1318 | self.assertEqual(list(dropwhile(isOdd, g(s))), tgt)
|
|---|
| 1319 | self.assertRaises(TypeError, dropwhile, isOdd, X(s))
|
|---|
| 1320 | self.assertRaises(TypeError, list, dropwhile(isOdd, N(s)))
|
|---|
| 1321 | self.assertRaises(ZeroDivisionError, list, dropwhile(isOdd, E(s)))
|
|---|
| 1322 |
|
|---|
| 1323 | def test_tee(self):
|
|---|
| 1324 | for s in ("123", "", range(1000), ('do', 1.2), xrange(2000,2200,5)):
|
|---|
| 1325 | for g in (G, I, Ig, S, L, R):
|
|---|
| 1326 | it1, it2 = tee(g(s))
|
|---|
| 1327 | self.assertEqual(list(it1), list(g(s)))
|
|---|
| 1328 | self.assertEqual(list(it2), list(g(s)))
|
|---|
| 1329 | self.assertRaises(TypeError, tee, X(s))
|
|---|
| 1330 | self.assertRaises(TypeError, list, tee(N(s))[0])
|
|---|
| 1331 | self.assertRaises(ZeroDivisionError, list, tee(E(s))[0])
|
|---|
| 1332 |
|
|---|
| 1333 | class LengthTransparency(unittest.TestCase):
|
|---|
| 1334 |
|
|---|
| 1335 | def test_repeat(self):
|
|---|
| 1336 | from test.test_iterlen import len
|
|---|
| 1337 | self.assertEqual(len(repeat(None, 50)), 50)
|
|---|
| 1338 | self.assertRaises(TypeError, len, repeat(None))
|
|---|
| 1339 |
|
|---|
| 1340 | class RegressionTests(unittest.TestCase):
|
|---|
| 1341 |
|
|---|
| 1342 | def test_sf_793826(self):
|
|---|
| 1343 | # Fix Armin Rigo's successful efforts to wreak havoc
|
|---|
| 1344 |
|
|---|
| 1345 | def mutatingtuple(tuple1, f, tuple2):
|
|---|
| 1346 | # this builds a tuple t which is a copy of tuple1,
|
|---|
| 1347 | # then calls f(t), then mutates t to be equal to tuple2
|
|---|
| 1348 | # (needs len(tuple1) == len(tuple2)).
|
|---|
| 1349 | def g(value, first=[1]):
|
|---|
| 1350 | if first:
|
|---|
| 1351 | del first[:]
|
|---|
| 1352 | f(z.next())
|
|---|
| 1353 | return value
|
|---|
| 1354 | items = list(tuple2)
|
|---|
| 1355 | items[1:1] = list(tuple1)
|
|---|
| 1356 | gen = imap(g, items)
|
|---|
| 1357 | z = izip(*[gen]*len(tuple1))
|
|---|
| 1358 | z.next()
|
|---|
| 1359 |
|
|---|
| 1360 | def f(t):
|
|---|
| 1361 | global T
|
|---|
| 1362 | T = t
|
|---|
| 1363 | first[:] = list(T)
|
|---|
| 1364 |
|
|---|
| 1365 | first = []
|
|---|
| 1366 | mutatingtuple((1,2,3), f, (4,5,6))
|
|---|
| 1367 | second = list(T)
|
|---|
| 1368 | self.assertEqual(first, second)
|
|---|
| 1369 |
|
|---|
| 1370 |
|
|---|
| 1371 | def test_sf_950057(self):
|
|---|
| 1372 | # Make sure that chain() and cycle() catch exceptions immediately
|
|---|
| 1373 | # rather than when shifting between input sources
|
|---|
| 1374 |
|
|---|
| 1375 | def gen1():
|
|---|
| 1376 | hist.append(0)
|
|---|
| 1377 | yield 1
|
|---|
| 1378 | hist.append(1)
|
|---|
| 1379 | raise AssertionError
|
|---|
| 1380 | hist.append(2)
|
|---|
| 1381 |
|
|---|
| 1382 | def gen2(x):
|
|---|
| 1383 | hist.append(3)
|
|---|
| 1384 | yield 2
|
|---|
| 1385 | hist.append(4)
|
|---|
| 1386 | if x:
|
|---|
| 1387 | raise StopIteration
|
|---|
| 1388 |
|
|---|
| 1389 | hist = []
|
|---|
| 1390 | self.assertRaises(AssertionError, list, chain(gen1(), gen2(False)))
|
|---|
| 1391 | self.assertEqual(hist, [0,1])
|
|---|
| 1392 |
|
|---|
| 1393 | hist = []
|
|---|
| 1394 | self.assertRaises(AssertionError, list, chain(gen1(), gen2(True)))
|
|---|
| 1395 | self.assertEqual(hist, [0,1])
|
|---|
| 1396 |
|
|---|
| 1397 | hist = []
|
|---|
| 1398 | self.assertRaises(AssertionError, list, cycle(gen1()))
|
|---|
| 1399 | self.assertEqual(hist, [0,1])
|
|---|
| 1400 |
|
|---|
| 1401 | class SubclassWithKwargsTest(unittest.TestCase):
|
|---|
| 1402 | def test_keywords_in_subclass(self):
|
|---|
| 1403 | # count is not subclassable...
|
|---|
| 1404 | for cls in (repeat, izip, ifilter, ifilterfalse, chain, imap,
|
|---|
| 1405 | starmap, islice, takewhile, dropwhile, cycle, compress):
|
|---|
| 1406 | class Subclass(cls):
|
|---|
| 1407 | def __init__(self, newarg=None, *args):
|
|---|
| 1408 | cls.__init__(self, *args)
|
|---|
| 1409 | try:
|
|---|
| 1410 | Subclass(newarg=1)
|
|---|
| 1411 | except TypeError, err:
|
|---|
| 1412 | # we expect type errors because of wrong argument count
|
|---|
| 1413 | self.assertNotIn("does not take keyword arguments", err.args[0])
|
|---|
| 1414 |
|
|---|
| 1415 |
|
|---|
| 1416 | libreftest = """ Doctest for examples in the library reference: libitertools.tex
|
|---|
| 1417 |
|
|---|
| 1418 |
|
|---|
| 1419 | >>> amounts = [120.15, 764.05, 823.14]
|
|---|
| 1420 | >>> for checknum, amount in izip(count(1200), amounts):
|
|---|
| 1421 | ... print 'Check %d is for $%.2f' % (checknum, amount)
|
|---|
| 1422 | ...
|
|---|
| 1423 | Check 1200 is for $120.15
|
|---|
| 1424 | Check 1201 is for $764.05
|
|---|
| 1425 | Check 1202 is for $823.14
|
|---|
| 1426 |
|
|---|
| 1427 | >>> import operator
|
|---|
| 1428 | >>> for cube in imap(operator.pow, xrange(1,4), repeat(3)):
|
|---|
| 1429 | ... print cube
|
|---|
| 1430 | ...
|
|---|
| 1431 | 1
|
|---|
| 1432 | 8
|
|---|
| 1433 | 27
|
|---|
| 1434 |
|
|---|
| 1435 | >>> reportlines = ['EuroPython', 'Roster', '', 'alex', '', 'laura', '', 'martin', '', 'walter', '', 'samuele']
|
|---|
| 1436 | >>> for name in islice(reportlines, 3, None, 2):
|
|---|
| 1437 | ... print name.title()
|
|---|
| 1438 | ...
|
|---|
| 1439 | Alex
|
|---|
| 1440 | Laura
|
|---|
| 1441 | Martin
|
|---|
| 1442 | Walter
|
|---|
| 1443 | Samuele
|
|---|
| 1444 |
|
|---|
| 1445 | >>> from operator import itemgetter
|
|---|
| 1446 | >>> d = dict(a=1, b=2, c=1, d=2, e=1, f=2, g=3)
|
|---|
| 1447 | >>> di = sorted(sorted(d.iteritems()), key=itemgetter(1))
|
|---|
| 1448 | >>> for k, g in groupby(di, itemgetter(1)):
|
|---|
| 1449 | ... print k, map(itemgetter(0), g)
|
|---|
| 1450 | ...
|
|---|
| 1451 | 1 ['a', 'c', 'e']
|
|---|
| 1452 | 2 ['b', 'd', 'f']
|
|---|
| 1453 | 3 ['g']
|
|---|
| 1454 |
|
|---|
| 1455 | # Find runs of consecutive numbers using groupby. The key to the solution
|
|---|
| 1456 | # is differencing with a range so that consecutive numbers all appear in
|
|---|
| 1457 | # same group.
|
|---|
| 1458 | >>> data = [ 1, 4,5,6, 10, 15,16,17,18, 22, 25,26,27,28]
|
|---|
| 1459 | >>> for k, g in groupby(enumerate(data), lambda t:t[0]-t[1]):
|
|---|
| 1460 | ... print map(operator.itemgetter(1), g)
|
|---|
| 1461 | ...
|
|---|
| 1462 | [1]
|
|---|
| 1463 | [4, 5, 6]
|
|---|
| 1464 | [10]
|
|---|
| 1465 | [15, 16, 17, 18]
|
|---|
| 1466 | [22]
|
|---|
| 1467 | [25, 26, 27, 28]
|
|---|
| 1468 |
|
|---|
| 1469 | >>> def take(n, iterable):
|
|---|
| 1470 | ... "Return first n items of the iterable as a list"
|
|---|
| 1471 | ... return list(islice(iterable, n))
|
|---|
| 1472 |
|
|---|
| 1473 | >>> def enumerate(iterable, start=0):
|
|---|
| 1474 | ... return izip(count(start), iterable)
|
|---|
| 1475 |
|
|---|
| 1476 | >>> def tabulate(function, start=0):
|
|---|
| 1477 | ... "Return function(0), function(1), ..."
|
|---|
| 1478 | ... return imap(function, count(start))
|
|---|
| 1479 |
|
|---|
| 1480 | >>> def nth(iterable, n, default=None):
|
|---|
| 1481 | ... "Returns the nth item or a default value"
|
|---|
| 1482 | ... return next(islice(iterable, n, None), default)
|
|---|
| 1483 |
|
|---|
| 1484 | >>> def quantify(iterable, pred=bool):
|
|---|
| 1485 | ... "Count how many times the predicate is true"
|
|---|
| 1486 | ... return sum(imap(pred, iterable))
|
|---|
| 1487 |
|
|---|
| 1488 | >>> def padnone(iterable):
|
|---|
| 1489 | ... "Returns the sequence elements and then returns None indefinitely"
|
|---|
| 1490 | ... return chain(iterable, repeat(None))
|
|---|
| 1491 |
|
|---|
| 1492 | >>> def ncycles(iterable, n):
|
|---|
| 1493 | ... "Returns the sequence elements n times"
|
|---|
| 1494 | ... return chain(*repeat(iterable, n))
|
|---|
| 1495 |
|
|---|
| 1496 | >>> def dotproduct(vec1, vec2):
|
|---|
| 1497 | ... return sum(imap(operator.mul, vec1, vec2))
|
|---|
| 1498 |
|
|---|
| 1499 | >>> def flatten(listOfLists):
|
|---|
| 1500 | ... return list(chain.from_iterable(listOfLists))
|
|---|
| 1501 |
|
|---|
| 1502 | >>> def repeatfunc(func, times=None, *args):
|
|---|
| 1503 | ... "Repeat calls to func with specified arguments."
|
|---|
| 1504 | ... " Example: repeatfunc(random.random)"
|
|---|
| 1505 | ... if times is None:
|
|---|
| 1506 | ... return starmap(func, repeat(args))
|
|---|
| 1507 | ... else:
|
|---|
| 1508 | ... return starmap(func, repeat(args, times))
|
|---|
| 1509 |
|
|---|
| 1510 | >>> def pairwise(iterable):
|
|---|
| 1511 | ... "s -> (s0,s1), (s1,s2), (s2, s3), ..."
|
|---|
| 1512 | ... a, b = tee(iterable)
|
|---|
| 1513 | ... for elem in b:
|
|---|
| 1514 | ... break
|
|---|
| 1515 | ... return izip(a, b)
|
|---|
| 1516 |
|
|---|
| 1517 | >>> def grouper(n, iterable, fillvalue=None):
|
|---|
| 1518 | ... "grouper(3, 'ABCDEFG', 'x') --> ABC DEF Gxx"
|
|---|
| 1519 | ... args = [iter(iterable)] * n
|
|---|
| 1520 | ... return izip_longest(fillvalue=fillvalue, *args)
|
|---|
| 1521 |
|
|---|
| 1522 | >>> def roundrobin(*iterables):
|
|---|
| 1523 | ... "roundrobin('ABC', 'D', 'EF') --> A D E B F C"
|
|---|
| 1524 | ... # Recipe credited to George Sakkis
|
|---|
| 1525 | ... pending = len(iterables)
|
|---|
| 1526 | ... nexts = cycle(iter(it).next for it in iterables)
|
|---|
| 1527 | ... while pending:
|
|---|
| 1528 | ... try:
|
|---|
| 1529 | ... for next in nexts:
|
|---|
| 1530 | ... yield next()
|
|---|
| 1531 | ... except StopIteration:
|
|---|
| 1532 | ... pending -= 1
|
|---|
| 1533 | ... nexts = cycle(islice(nexts, pending))
|
|---|
| 1534 |
|
|---|
| 1535 | >>> def powerset(iterable):
|
|---|
| 1536 | ... "powerset([1,2,3]) --> () (1,) (2,) (3,) (1,2) (1,3) (2,3) (1,2,3)"
|
|---|
| 1537 | ... s = list(iterable)
|
|---|
| 1538 | ... return chain.from_iterable(combinations(s, r) for r in range(len(s)+1))
|
|---|
| 1539 |
|
|---|
| 1540 | >>> def unique_everseen(iterable, key=None):
|
|---|
| 1541 | ... "List unique elements, preserving order. Remember all elements ever seen."
|
|---|
| 1542 | ... # unique_everseen('AAAABBBCCDAABBB') --> A B C D
|
|---|
| 1543 | ... # unique_everseen('ABBCcAD', str.lower) --> A B C D
|
|---|
| 1544 | ... seen = set()
|
|---|
| 1545 | ... seen_add = seen.add
|
|---|
| 1546 | ... if key is None:
|
|---|
| 1547 | ... for element in iterable:
|
|---|
| 1548 | ... if element not in seen:
|
|---|
| 1549 | ... seen_add(element)
|
|---|
| 1550 | ... yield element
|
|---|
| 1551 | ... else:
|
|---|
| 1552 | ... for element in iterable:
|
|---|
| 1553 | ... k = key(element)
|
|---|
| 1554 | ... if k not in seen:
|
|---|
| 1555 | ... seen_add(k)
|
|---|
| 1556 | ... yield element
|
|---|
| 1557 |
|
|---|
| 1558 | >>> def unique_justseen(iterable, key=None):
|
|---|
| 1559 | ... "List unique elements, preserving order. Remember only the element just seen."
|
|---|
| 1560 | ... # unique_justseen('AAAABBBCCDAABBB') --> A B C D A B
|
|---|
| 1561 | ... # unique_justseen('ABBCcAD', str.lower) --> A B C A D
|
|---|
| 1562 | ... return imap(next, imap(itemgetter(1), groupby(iterable, key)))
|
|---|
| 1563 |
|
|---|
| 1564 | This is not part of the examples but it tests to make sure the definitions
|
|---|
| 1565 | perform as purported.
|
|---|
| 1566 |
|
|---|
| 1567 | >>> take(10, count())
|
|---|
| 1568 | [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
|
|---|
| 1569 |
|
|---|
| 1570 | >>> list(enumerate('abc'))
|
|---|
| 1571 | [(0, 'a'), (1, 'b'), (2, 'c')]
|
|---|
| 1572 |
|
|---|
| 1573 | >>> list(islice(tabulate(lambda x: 2*x), 4))
|
|---|
| 1574 | [0, 2, 4, 6]
|
|---|
| 1575 |
|
|---|
| 1576 | >>> nth('abcde', 3)
|
|---|
| 1577 | 'd'
|
|---|
| 1578 |
|
|---|
| 1579 | >>> nth('abcde', 9) is None
|
|---|
| 1580 | True
|
|---|
| 1581 |
|
|---|
| 1582 | >>> quantify(xrange(99), lambda x: x%2==0)
|
|---|
| 1583 | 50
|
|---|
| 1584 |
|
|---|
| 1585 | >>> a = [[1, 2, 3], [4, 5, 6]]
|
|---|
| 1586 | >>> flatten(a)
|
|---|
| 1587 | [1, 2, 3, 4, 5, 6]
|
|---|
| 1588 |
|
|---|
| 1589 | >>> list(repeatfunc(pow, 5, 2, 3))
|
|---|
| 1590 | [8, 8, 8, 8, 8]
|
|---|
| 1591 |
|
|---|
| 1592 | >>> import random
|
|---|
| 1593 | >>> take(5, imap(int, repeatfunc(random.random)))
|
|---|
| 1594 | [0, 0, 0, 0, 0]
|
|---|
| 1595 |
|
|---|
| 1596 | >>> list(pairwise('abcd'))
|
|---|
| 1597 | [('a', 'b'), ('b', 'c'), ('c', 'd')]
|
|---|
| 1598 |
|
|---|
| 1599 | >>> list(pairwise([]))
|
|---|
| 1600 | []
|
|---|
| 1601 |
|
|---|
| 1602 | >>> list(pairwise('a'))
|
|---|
| 1603 | []
|
|---|
| 1604 |
|
|---|
| 1605 | >>> list(islice(padnone('abc'), 0, 6))
|
|---|
| 1606 | ['a', 'b', 'c', None, None, None]
|
|---|
| 1607 |
|
|---|
| 1608 | >>> list(ncycles('abc', 3))
|
|---|
| 1609 | ['a', 'b', 'c', 'a', 'b', 'c', 'a', 'b', 'c']
|
|---|
| 1610 |
|
|---|
| 1611 | >>> dotproduct([1,2,3], [4,5,6])
|
|---|
| 1612 | 32
|
|---|
| 1613 |
|
|---|
| 1614 | >>> list(grouper(3, 'abcdefg', 'x'))
|
|---|
| 1615 | [('a', 'b', 'c'), ('d', 'e', 'f'), ('g', 'x', 'x')]
|
|---|
| 1616 |
|
|---|
| 1617 | >>> list(roundrobin('abc', 'd', 'ef'))
|
|---|
| 1618 | ['a', 'd', 'e', 'b', 'f', 'c']
|
|---|
| 1619 |
|
|---|
| 1620 | >>> list(powerset([1,2,3]))
|
|---|
| 1621 | [(), (1,), (2,), (3,), (1, 2), (1, 3), (2, 3), (1, 2, 3)]
|
|---|
| 1622 |
|
|---|
| 1623 | >>> all(len(list(powerset(range(n)))) == 2**n for n in range(18))
|
|---|
| 1624 | True
|
|---|
| 1625 |
|
|---|
| 1626 | >>> list(powerset('abcde')) == sorted(sorted(set(powerset('abcde'))), key=len)
|
|---|
| 1627 | True
|
|---|
| 1628 |
|
|---|
| 1629 | >>> list(unique_everseen('AAAABBBCCDAABBB'))
|
|---|
| 1630 | ['A', 'B', 'C', 'D']
|
|---|
| 1631 |
|
|---|
| 1632 | >>> list(unique_everseen('ABBCcAD', str.lower))
|
|---|
| 1633 | ['A', 'B', 'C', 'D']
|
|---|
| 1634 |
|
|---|
| 1635 | >>> list(unique_justseen('AAAABBBCCDAABBB'))
|
|---|
| 1636 | ['A', 'B', 'C', 'D', 'A', 'B']
|
|---|
| 1637 |
|
|---|
| 1638 | >>> list(unique_justseen('ABBCcAD', str.lower))
|
|---|
| 1639 | ['A', 'B', 'C', 'A', 'D']
|
|---|
| 1640 |
|
|---|
| 1641 | """
|
|---|
| 1642 |
|
|---|
| 1643 | __test__ = {'libreftest' : libreftest}
|
|---|
| 1644 |
|
|---|
| 1645 | def test_main(verbose=None):
|
|---|
| 1646 | test_classes = (TestBasicOps, TestVariousIteratorArgs, TestGC,
|
|---|
| 1647 | RegressionTests, LengthTransparency,
|
|---|
| 1648 | SubclassWithKwargsTest, TestExamples)
|
|---|
| 1649 | test_support.run_unittest(*test_classes)
|
|---|
| 1650 |
|
|---|
| 1651 | # verify reference counting
|
|---|
| 1652 | if verbose and hasattr(sys, "gettotalrefcount"):
|
|---|
| 1653 | import gc
|
|---|
| 1654 | counts = [None] * 5
|
|---|
| 1655 | for i in xrange(len(counts)):
|
|---|
| 1656 | test_support.run_unittest(*test_classes)
|
|---|
| 1657 | gc.collect()
|
|---|
| 1658 | counts[i] = sys.gettotalrefcount()
|
|---|
| 1659 | print counts
|
|---|
| 1660 |
|
|---|
| 1661 | # doctest the examples in the library reference
|
|---|
| 1662 | test_support.run_doctest(sys.modules[__name__], verbose)
|
|---|
| 1663 |
|
|---|
| 1664 | if __name__ == "__main__":
|
|---|
| 1665 | test_main(verbose=True)
|
|---|
