1213 lines
46 KiB
Python
1213 lines
46 KiB
Python
import unittest
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from test import test_support
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from itertools import *
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from weakref import proxy
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import sys
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import operator
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import random
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maxsize = test_support.MAX_Py_ssize_t
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minsize = -maxsize-1
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def onearg(x):
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'Test function of one argument'
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return 2*x
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def errfunc(*args):
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'Test function that raises an error'
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raise ValueError
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def gen3():
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'Non-restartable source sequence'
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for i in (0, 1, 2):
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yield i
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def isEven(x):
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'Test predicate'
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return x%2==0
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def isOdd(x):
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'Test predicate'
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return x%2==1
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class StopNow:
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'Class emulating an empty iterable.'
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def __iter__(self):
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return self
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def next(self):
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raise StopIteration
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def take(n, seq):
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'Convenience function for partially consuming a long of infinite iterable'
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return list(islice(seq, n))
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def prod(iterable):
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return reduce(operator.mul, iterable, 1)
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def fact(n):
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'Factorial'
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return prod(range(1, n+1))
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class TestBasicOps(unittest.TestCase):
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def test_chain(self):
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self.assertEqual(list(chain('abc', 'def')), list('abcdef'))
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self.assertEqual(list(chain('abc')), list('abc'))
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self.assertEqual(list(chain('')), [])
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self.assertEqual(take(4, chain('abc', 'def')), list('abcd'))
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self.assertRaises(TypeError, list,chain(2, 3))
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def test_chain_from_iterable(self):
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self.assertEqual(list(chain.from_iterable(['abc', 'def'])), list('abcdef'))
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self.assertEqual(list(chain.from_iterable(['abc'])), list('abc'))
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self.assertEqual(list(chain.from_iterable([''])), [])
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self.assertEqual(take(4, chain.from_iterable(['abc', 'def'])), list('abcd'))
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self.assertRaises(TypeError, list, chain.from_iterable([2, 3]))
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def test_combinations(self):
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self.assertRaises(TypeError, combinations, 'abc') # missing r argument
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self.assertRaises(TypeError, combinations, 'abc', 2, 1) # too many arguments
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self.assertRaises(TypeError, combinations, None) # pool is not iterable
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self.assertRaises(ValueError, combinations, 'abc', -2) # r is negative
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self.assertRaises(ValueError, combinations, 'abc', 32) # r is too big
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self.assertEqual(list(combinations(range(4), 3)),
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[(0,1,2), (0,1,3), (0,2,3), (1,2,3)])
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def combinations1(iterable, r):
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'Pure python version shown in the docs'
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pool = tuple(iterable)
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n = len(pool)
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indices = range(r)
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yield tuple(pool[i] for i in indices)
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while 1:
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for i in reversed(range(r)):
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if indices[i] != i + n - r:
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break
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else:
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return
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indices[i] += 1
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for j in range(i+1, r):
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indices[j] = indices[j-1] + 1
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yield tuple(pool[i] for i in indices)
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def combinations2(iterable, r):
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'Pure python version shown in the docs'
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pool = tuple(iterable)
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n = len(pool)
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for indices in permutations(range(n), r):
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if sorted(indices) == list(indices):
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yield tuple(pool[i] for i in indices)
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for n in range(7):
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values = [5*x-12 for x in range(n)]
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for r in range(n+1):
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result = list(combinations(values, r))
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self.assertEqual(len(result), fact(n) / fact(r) / fact(n-r)) # right number of combs
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self.assertEqual(len(result), len(set(result))) # no repeats
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self.assertEqual(result, sorted(result)) # lexicographic order
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for c in result:
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self.assertEqual(len(c), r) # r-length combinations
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self.assertEqual(len(set(c)), r) # no duplicate elements
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self.assertEqual(list(c), sorted(c)) # keep original ordering
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self.assert_(all(e in values for e in c)) # elements taken from input iterable
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self.assertEqual(list(c),
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[e for e in values if e in c]) # comb is a subsequence of the input iterable
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self.assertEqual(result, list(combinations1(values, r))) # matches first pure python version
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self.assertEqual(result, list(combinations2(values, r))) # matches first pure python version
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# Test implementation detail: tuple re-use
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self.assertEqual(len(set(map(id, combinations('abcde', 3)))), 1)
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self.assertNotEqual(len(set(map(id, list(combinations('abcde', 3))))), 1)
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def test_permutations(self):
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self.assertRaises(TypeError, permutations) # too few arguments
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self.assertRaises(TypeError, permutations, 'abc', 2, 1) # too many arguments
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self.assertRaises(TypeError, permutations, None) # pool is not iterable
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self.assertRaises(ValueError, permutations, 'abc', -2) # r is negative
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self.assertRaises(ValueError, permutations, 'abc', 32) # r is too big
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self.assertRaises(TypeError, permutations, 'abc', 's') # r is not an int or None
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self.assertEqual(list(permutations(range(3), 2)),
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[(0,1), (0,2), (1,0), (1,2), (2,0), (2,1)])
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def permutations1(iterable, r=None):
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'Pure python version shown in the docs'
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pool = tuple(iterable)
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n = len(pool)
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r = n if r is None else r
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indices = range(n)
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cycles = range(n-r+1, n+1)[::-1]
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yield tuple(pool[i] for i in indices[:r])
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while n:
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for i in reversed(range(r)):
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cycles[i] -= 1
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if cycles[i] == 0:
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indices[i:] = indices[i+1:] + indices[i:i+1]
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cycles[i] = n - i
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else:
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j = cycles[i]
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indices[i], indices[-j] = indices[-j], indices[i]
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yield tuple(pool[i] for i in indices[:r])
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break
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else:
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return
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def permutations2(iterable, r=None):
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'Pure python version shown in the docs'
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pool = tuple(iterable)
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n = len(pool)
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r = n if r is None else r
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for indices in product(range(n), repeat=r):
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if len(set(indices)) == r:
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yield tuple(pool[i] for i in indices)
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for n in range(7):
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values = [5*x-12 for x in range(n)]
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for r in range(n+1):
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result = list(permutations(values, r))
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self.assertEqual(len(result), fact(n) / fact(n-r)) # right number of perms
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self.assertEqual(len(result), len(set(result))) # no repeats
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self.assertEqual(result, sorted(result)) # lexicographic order
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for p in result:
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self.assertEqual(len(p), r) # r-length permutations
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self.assertEqual(len(set(p)), r) # no duplicate elements
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self.assert_(all(e in values for e in p)) # elements taken from input iterable
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self.assertEqual(result, list(permutations1(values, r))) # matches first pure python version
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self.assertEqual(result, list(permutations2(values, r))) # matches first pure python version
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if r == n:
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self.assertEqual(result, list(permutations(values, None))) # test r as None
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self.assertEqual(result, list(permutations(values))) # test default r
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# Test implementation detail: tuple re-use
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self.assertEqual(len(set(map(id, permutations('abcde', 3)))), 1)
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self.assertNotEqual(len(set(map(id, list(permutations('abcde', 3))))), 1)
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def test_count(self):
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self.assertEqual(zip('abc',count()), [('a', 0), ('b', 1), ('c', 2)])
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self.assertEqual(zip('abc',count(3)), [('a', 3), ('b', 4), ('c', 5)])
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self.assertEqual(take(2, zip('abc',count(3))), [('a', 3), ('b', 4)])
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self.assertEqual(take(2, zip('abc',count(-1))), [('a', -1), ('b', 0)])
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self.assertEqual(take(2, zip('abc',count(-3))), [('a', -3), ('b', -2)])
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self.assertRaises(TypeError, count, 2, 3)
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self.assertRaises(TypeError, count, 'a')
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self.assertEqual(list(islice(count(maxsize-5), 10)), range(maxsize-5, maxsize+5))
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self.assertEqual(list(islice(count(-maxsize-5), 10)), range(-maxsize-5, -maxsize+5))
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c = count(3)
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self.assertEqual(repr(c), 'count(3)')
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c.next()
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self.assertEqual(repr(c), 'count(4)')
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c = count(-9)
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self.assertEqual(repr(c), 'count(-9)')
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c.next()
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self.assertEqual(c.next(), -8)
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for i in (-sys.maxint-5, -sys.maxint+5 ,-10, -1, 0, 10, sys.maxint-5, sys.maxint+5):
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# Test repr (ignoring the L in longs)
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r1 = repr(count(i)).replace('L', '')
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r2 = 'count(%r)'.__mod__(i).replace('L', '')
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self.assertEqual(r1, r2)
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def test_cycle(self):
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self.assertEqual(take(10, cycle('abc')), list('abcabcabca'))
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self.assertEqual(list(cycle('')), [])
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self.assertRaises(TypeError, cycle)
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self.assertRaises(TypeError, cycle, 5)
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self.assertEqual(list(islice(cycle(gen3()),10)), [0,1,2,0,1,2,0,1,2,0])
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def test_groupby(self):
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# Check whether it accepts arguments correctly
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self.assertEqual([], list(groupby([])))
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self.assertEqual([], list(groupby([], key=id)))
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self.assertRaises(TypeError, list, groupby('abc', []))
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self.assertRaises(TypeError, groupby, None)
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self.assertRaises(TypeError, groupby, 'abc', lambda x:x, 10)
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# Check normal input
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s = [(0, 10, 20), (0, 11,21), (0,12,21), (1,13,21), (1,14,22),
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(2,15,22), (3,16,23), (3,17,23)]
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dup = []
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for k, g in groupby(s, lambda r:r[0]):
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for elem in g:
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self.assertEqual(k, elem[0])
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dup.append(elem)
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self.assertEqual(s, dup)
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# Check nested case
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dup = []
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for k, g in groupby(s, lambda r:r[0]):
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for ik, ig in groupby(g, lambda r:r[2]):
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for elem in ig:
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self.assertEqual(k, elem[0])
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self.assertEqual(ik, elem[2])
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dup.append(elem)
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self.assertEqual(s, dup)
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# Check case where inner iterator is not used
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keys = [k for k, g in groupby(s, lambda r:r[0])]
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expectedkeys = set([r[0] for r in s])
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self.assertEqual(set(keys), expectedkeys)
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self.assertEqual(len(keys), len(expectedkeys))
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# Exercise pipes and filters style
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s = 'abracadabra'
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# sort s | uniq
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r = [k for k, g in groupby(sorted(s))]
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self.assertEqual(r, ['a', 'b', 'c', 'd', 'r'])
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# sort s | uniq -d
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r = [k for k, g in groupby(sorted(s)) if list(islice(g,1,2))]
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self.assertEqual(r, ['a', 'b', 'r'])
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# sort s | uniq -c
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r = [(len(list(g)), k) for k, g in groupby(sorted(s))]
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self.assertEqual(r, [(5, 'a'), (2, 'b'), (1, 'c'), (1, 'd'), (2, 'r')])
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# sort s | uniq -c | sort -rn | head -3
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r = sorted([(len(list(g)) , k) for k, g in groupby(sorted(s))], reverse=True)[:3]
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self.assertEqual(r, [(5, 'a'), (2, 'r'), (2, 'b')])
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# iter.next failure
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class ExpectedError(Exception):
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pass
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def delayed_raise(n=0):
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for i in range(n):
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yield 'yo'
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raise ExpectedError
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def gulp(iterable, keyp=None, func=list):
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return [func(g) for k, g in groupby(iterable, keyp)]
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# iter.next failure on outer object
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self.assertRaises(ExpectedError, gulp, delayed_raise(0))
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# iter.next failure on inner object
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self.assertRaises(ExpectedError, gulp, delayed_raise(1))
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# __cmp__ failure
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class DummyCmp:
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def __cmp__(self, dst):
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raise ExpectedError
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s = [DummyCmp(), DummyCmp(), None]
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# __cmp__ failure on outer object
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self.assertRaises(ExpectedError, gulp, s, func=id)
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# __cmp__ failure on inner object
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self.assertRaises(ExpectedError, gulp, s)
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# keyfunc failure
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def keyfunc(obj):
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if keyfunc.skip > 0:
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keyfunc.skip -= 1
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return obj
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else:
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raise ExpectedError
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# keyfunc failure on outer object
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keyfunc.skip = 0
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self.assertRaises(ExpectedError, gulp, [None], keyfunc)
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keyfunc.skip = 1
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self.assertRaises(ExpectedError, gulp, [None, None], keyfunc)
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def test_ifilter(self):
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self.assertEqual(list(ifilter(isEven, range(6))), [0,2,4])
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self.assertEqual(list(ifilter(None, [0,1,0,2,0])), [1,2])
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self.assertEqual(list(ifilter(bool, [0,1,0,2,0])), [1,2])
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self.assertEqual(take(4, ifilter(isEven, count())), [0,2,4,6])
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self.assertRaises(TypeError, ifilter)
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self.assertRaises(TypeError, ifilter, lambda x:x)
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self.assertRaises(TypeError, ifilter, lambda x:x, range(6), 7)
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self.assertRaises(TypeError, ifilter, isEven, 3)
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self.assertRaises(TypeError, ifilter(range(6), range(6)).next)
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def test_ifilterfalse(self):
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self.assertEqual(list(ifilterfalse(isEven, range(6))), [1,3,5])
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self.assertEqual(list(ifilterfalse(None, [0,1,0,2,0])), [0,0,0])
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self.assertEqual(list(ifilterfalse(bool, [0,1,0,2,0])), [0,0,0])
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self.assertEqual(take(4, ifilterfalse(isEven, count())), [1,3,5,7])
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self.assertRaises(TypeError, ifilterfalse)
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self.assertRaises(TypeError, ifilterfalse, lambda x:x)
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self.assertRaises(TypeError, ifilterfalse, lambda x:x, range(6), 7)
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self.assertRaises(TypeError, ifilterfalse, isEven, 3)
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self.assertRaises(TypeError, ifilterfalse(range(6), range(6)).next)
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def test_izip(self):
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ans = [(x,y) for x, y in izip('abc',count())]
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self.assertEqual(ans, [('a', 0), ('b', 1), ('c', 2)])
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self.assertEqual(list(izip('abc', range(6))), zip('abc', range(6)))
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self.assertEqual(list(izip('abcdef', range(3))), zip('abcdef', range(3)))
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self.assertEqual(take(3,izip('abcdef', count())), zip('abcdef', range(3)))
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self.assertEqual(list(izip('abcdef')), zip('abcdef'))
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self.assertEqual(list(izip()), zip())
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self.assertRaises(TypeError, izip, 3)
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self.assertRaises(TypeError, izip, range(3), 3)
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# Check tuple re-use (implementation detail)
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self.assertEqual([tuple(list(pair)) for pair in izip('abc', 'def')],
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zip('abc', 'def'))
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self.assertEqual([pair for pair in izip('abc', 'def')],
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zip('abc', 'def'))
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ids = map(id, izip('abc', 'def'))
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self.assertEqual(min(ids), max(ids))
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ids = map(id, list(izip('abc', 'def')))
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self.assertEqual(len(dict.fromkeys(ids)), len(ids))
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def test_iziplongest(self):
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for args in [
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['abc', range(6)],
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[range(6), 'abc'],
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[range(1000), range(2000,2100), range(3000,3050)],
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[range(1000), range(0), range(3000,3050), range(1200), range(1500)],
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[range(1000), range(0), range(3000,3050), range(1200), range(1500), range(0)],
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]:
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target = map(None, *args)
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self.assertEqual(list(izip_longest(*args)), target)
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self.assertEqual(list(izip_longest(*args, **{})), target)
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target = [tuple((e is None and 'X' or e) for e in t) for t in target] # Replace None fills with 'X'
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self.assertEqual(list(izip_longest(*args, **dict(fillvalue='X'))), target)
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self.assertEqual(take(3,izip_longest('abcdef', count())), zip('abcdef', range(3))) # take 3 from infinite input
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self.assertEqual(list(izip_longest()), zip())
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self.assertEqual(list(izip_longest([])), zip([]))
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self.assertEqual(list(izip_longest('abcdef')), zip('abcdef'))
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self.assertEqual(list(izip_longest('abc', 'defg', **{})), map(None, 'abc', 'defg')) # empty keyword dict
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self.assertRaises(TypeError, izip_longest, 3)
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self.assertRaises(TypeError, izip_longest, range(3), 3)
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for stmt in [
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"izip_longest('abc', fv=1)",
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"izip_longest('abc', fillvalue=1, bogus_keyword=None)",
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]:
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try:
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eval(stmt, globals(), locals())
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except TypeError:
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pass
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else:
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self.fail('Did not raise Type in: ' + stmt)
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# Check tuple re-use (implementation detail)
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self.assertEqual([tuple(list(pair)) for pair in izip_longest('abc', 'def')],
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zip('abc', 'def'))
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self.assertEqual([pair for pair in izip_longest('abc', 'def')],
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zip('abc', 'def'))
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ids = map(id, izip_longest('abc', 'def'))
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self.assertEqual(min(ids), max(ids))
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ids = map(id, list(izip_longest('abc', 'def')))
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self.assertEqual(len(dict.fromkeys(ids)), len(ids))
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def test_product(self):
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for args, result in [
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([], [()]), # zero iterables
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(['ab'], [('a',), ('b',)]), # one iterable
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([range(2), range(3)], [(0,0), (0,1), (0,2), (1,0), (1,1), (1,2)]), # two iterables
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([range(0), range(2), range(3)], []), # first iterable with zero length
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([range(2), range(0), range(3)], []), # middle iterable with zero length
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([range(2), range(3), range(0)], []), # last iterable with zero length
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]:
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self.assertEqual(list(product(*args)), result)
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for r in range(4):
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self.assertEqual(list(product(*(args*r))),
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list(product(*args, **dict(repeat=r))))
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self.assertEqual(len(list(product(*[range(7)]*6))), 7**6)
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self.assertRaises(TypeError, product, range(6), None)
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def product2(*args, **kwds):
|
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'Pure python version used in docs'
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pools = map(tuple, args) * kwds.get('repeat', 1)
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result = [[]]
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for pool in pools:
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result = [x+[y] for x in result for y in pool]
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for prod in result:
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yield tuple(prod)
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|
|
argtypes = ['', 'abc', '', xrange(0), xrange(4), dict(a=1, b=2, c=3),
|
|
set('abcdefg'), range(11), tuple(range(13))]
|
|
for i in range(100):
|
|
args = [random.choice(argtypes) for j in range(random.randrange(5))]
|
|
expected_len = prod(map(len, args))
|
|
self.assertEqual(len(list(product(*args))), expected_len)
|
|
self.assertEqual(list(product(*args)), list(product2(*args)))
|
|
args = map(iter, args)
|
|
self.assertEqual(len(list(product(*args))), expected_len)
|
|
|
|
# Test implementation detail: tuple re-use
|
|
self.assertEqual(len(set(map(id, product('abc', 'def')))), 1)
|
|
self.assertNotEqual(len(set(map(id, list(product('abc', 'def'))))), 1)
|
|
|
|
def test_repeat(self):
|
|
self.assertEqual(zip(xrange(3),repeat('a')),
|
|
[(0, 'a'), (1, 'a'), (2, 'a')])
|
|
self.assertEqual(list(repeat('a', 3)), ['a', 'a', 'a'])
|
|
self.assertEqual(take(3, repeat('a')), ['a', 'a', 'a'])
|
|
self.assertEqual(list(repeat('a', 0)), [])
|
|
self.assertEqual(list(repeat('a', -3)), [])
|
|
self.assertRaises(TypeError, repeat)
|
|
self.assertRaises(TypeError, repeat, None, 3, 4)
|
|
self.assertRaises(TypeError, repeat, None, 'a')
|
|
r = repeat(1+0j)
|
|
self.assertEqual(repr(r), 'repeat((1+0j))')
|
|
r = repeat(1+0j, 5)
|
|
self.assertEqual(repr(r), 'repeat((1+0j), 5)')
|
|
list(r)
|
|
self.assertEqual(repr(r), 'repeat((1+0j), 0)')
|
|
|
|
def test_imap(self):
|
|
self.assertEqual(list(imap(operator.pow, range(3), range(1,7))),
|
|
[0**1, 1**2, 2**3])
|
|
self.assertEqual(list(imap(None, 'abc', range(5))),
|
|
[('a',0),('b',1),('c',2)])
|
|
self.assertEqual(list(imap(None, 'abc', count())),
|
|
[('a',0),('b',1),('c',2)])
|
|
self.assertEqual(take(2,imap(None, 'abc', count())),
|
|
[('a',0),('b',1)])
|
|
self.assertEqual(list(imap(operator.pow, [])), [])
|
|
self.assertRaises(TypeError, imap)
|
|
self.assertRaises(TypeError, imap, operator.neg)
|
|
self.assertRaises(TypeError, imap(10, range(5)).next)
|
|
self.assertRaises(ValueError, imap(errfunc, [4], [5]).next)
|
|
self.assertRaises(TypeError, imap(onearg, [4], [5]).next)
|
|
|
|
def test_starmap(self):
|
|
self.assertEqual(list(starmap(operator.pow, zip(range(3), range(1,7)))),
|
|
[0**1, 1**2, 2**3])
|
|
self.assertEqual(take(3, starmap(operator.pow, izip(count(), count(1)))),
|
|
[0**1, 1**2, 2**3])
|
|
self.assertEqual(list(starmap(operator.pow, [])), [])
|
|
self.assertEqual(list(starmap(operator.pow, [iter([4,5])])), [4**5])
|
|
self.assertRaises(TypeError, list, starmap(operator.pow, [None]))
|
|
self.assertRaises(TypeError, starmap)
|
|
self.assertRaises(TypeError, starmap, operator.pow, [(4,5)], 'extra')
|
|
self.assertRaises(TypeError, starmap(10, [(4,5)]).next)
|
|
self.assertRaises(ValueError, starmap(errfunc, [(4,5)]).next)
|
|
self.assertRaises(TypeError, starmap(onearg, [(4,5)]).next)
|
|
|
|
def test_islice(self):
|
|
for args in [ # islice(args) should agree with range(args)
|
|
(10, 20, 3),
|
|
(10, 3, 20),
|
|
(10, 20),
|
|
(10, 3),
|
|
(20,)
|
|
]:
|
|
self.assertEqual(list(islice(xrange(100), *args)), range(*args))
|
|
|
|
for args, tgtargs in [ # Stop when seqn is exhausted
|
|
((10, 110, 3), ((10, 100, 3))),
|
|
((10, 110), ((10, 100))),
|
|
((110,), (100,))
|
|
]:
|
|
self.assertEqual(list(islice(xrange(100), *args)), range(*tgtargs))
|
|
|
|
# Test stop=None
|
|
self.assertEqual(list(islice(xrange(10), None)), range(10))
|
|
self.assertEqual(list(islice(xrange(10), None, None)), range(10))
|
|
self.assertEqual(list(islice(xrange(10), None, None, None)), range(10))
|
|
self.assertEqual(list(islice(xrange(10), 2, None)), range(2, 10))
|
|
self.assertEqual(list(islice(xrange(10), 1, None, 2)), range(1, 10, 2))
|
|
|
|
# Test number of items consumed SF #1171417
|
|
it = iter(range(10))
|
|
self.assertEqual(list(islice(it, 3)), range(3))
|
|
self.assertEqual(list(it), range(3, 10))
|
|
|
|
# Test invalid arguments
|
|
self.assertRaises(TypeError, islice, xrange(10))
|
|
self.assertRaises(TypeError, islice, xrange(10), 1, 2, 3, 4)
|
|
self.assertRaises(ValueError, islice, xrange(10), -5, 10, 1)
|
|
self.assertRaises(ValueError, islice, xrange(10), 1, -5, -1)
|
|
self.assertRaises(ValueError, islice, xrange(10), 1, 10, -1)
|
|
self.assertRaises(ValueError, islice, xrange(10), 1, 10, 0)
|
|
self.assertRaises(ValueError, islice, xrange(10), 'a')
|
|
self.assertRaises(ValueError, islice, xrange(10), 'a', 1)
|
|
self.assertRaises(ValueError, islice, xrange(10), 1, 'a')
|
|
self.assertRaises(ValueError, islice, xrange(10), 'a', 1, 1)
|
|
self.assertRaises(ValueError, islice, xrange(10), 1, 'a', 1)
|
|
self.assertEqual(len(list(islice(count(), 1, 10, maxsize))), 1)
|
|
|
|
def test_takewhile(self):
|
|
data = [1, 3, 5, 20, 2, 4, 6, 8]
|
|
underten = lambda x: x<10
|
|
self.assertEqual(list(takewhile(underten, data)), [1, 3, 5])
|
|
self.assertEqual(list(takewhile(underten, [])), [])
|
|
self.assertRaises(TypeError, takewhile)
|
|
self.assertRaises(TypeError, takewhile, operator.pow)
|
|
self.assertRaises(TypeError, takewhile, operator.pow, [(4,5)], 'extra')
|
|
self.assertRaises(TypeError, takewhile(10, [(4,5)]).next)
|
|
self.assertRaises(ValueError, takewhile(errfunc, [(4,5)]).next)
|
|
t = takewhile(bool, [1, 1, 1, 0, 0, 0])
|
|
self.assertEqual(list(t), [1, 1, 1])
|
|
self.assertRaises(StopIteration, t.next)
|
|
|
|
def test_dropwhile(self):
|
|
data = [1, 3, 5, 20, 2, 4, 6, 8]
|
|
underten = lambda x: x<10
|
|
self.assertEqual(list(dropwhile(underten, data)), [20, 2, 4, 6, 8])
|
|
self.assertEqual(list(dropwhile(underten, [])), [])
|
|
self.assertRaises(TypeError, dropwhile)
|
|
self.assertRaises(TypeError, dropwhile, operator.pow)
|
|
self.assertRaises(TypeError, dropwhile, operator.pow, [(4,5)], 'extra')
|
|
self.assertRaises(TypeError, dropwhile(10, [(4,5)]).next)
|
|
self.assertRaises(ValueError, dropwhile(errfunc, [(4,5)]).next)
|
|
|
|
def test_tee(self):
|
|
n = 200
|
|
def irange(n):
|
|
for i in xrange(n):
|
|
yield i
|
|
|
|
a, b = tee([]) # test empty iterator
|
|
self.assertEqual(list(a), [])
|
|
self.assertEqual(list(b), [])
|
|
|
|
a, b = tee(irange(n)) # test 100% interleaved
|
|
self.assertEqual(zip(a,b), zip(range(n),range(n)))
|
|
|
|
a, b = tee(irange(n)) # test 0% interleaved
|
|
self.assertEqual(list(a), range(n))
|
|
self.assertEqual(list(b), range(n))
|
|
|
|
a, b = tee(irange(n)) # test dealloc of leading iterator
|
|
for i in xrange(100):
|
|
self.assertEqual(a.next(), i)
|
|
del a
|
|
self.assertEqual(list(b), range(n))
|
|
|
|
a, b = tee(irange(n)) # test dealloc of trailing iterator
|
|
for i in xrange(100):
|
|
self.assertEqual(a.next(), i)
|
|
del b
|
|
self.assertEqual(list(a), range(100, n))
|
|
|
|
for j in xrange(5): # test randomly interleaved
|
|
order = [0]*n + [1]*n
|
|
random.shuffle(order)
|
|
lists = ([], [])
|
|
its = tee(irange(n))
|
|
for i in order:
|
|
value = its[i].next()
|
|
lists[i].append(value)
|
|
self.assertEqual(lists[0], range(n))
|
|
self.assertEqual(lists[1], range(n))
|
|
|
|
# test argument format checking
|
|
self.assertRaises(TypeError, tee)
|
|
self.assertRaises(TypeError, tee, 3)
|
|
self.assertRaises(TypeError, tee, [1,2], 'x')
|
|
self.assertRaises(TypeError, tee, [1,2], 3, 'x')
|
|
|
|
# tee object should be instantiable
|
|
a, b = tee('abc')
|
|
c = type(a)('def')
|
|
self.assertEqual(list(c), list('def'))
|
|
|
|
# test long-lagged and multi-way split
|
|
a, b, c = tee(xrange(2000), 3)
|
|
for i in xrange(100):
|
|
self.assertEqual(a.next(), i)
|
|
self.assertEqual(list(b), range(2000))
|
|
self.assertEqual([c.next(), c.next()], range(2))
|
|
self.assertEqual(list(a), range(100,2000))
|
|
self.assertEqual(list(c), range(2,2000))
|
|
|
|
# test values of n
|
|
self.assertRaises(TypeError, tee, 'abc', 'invalid')
|
|
self.assertRaises(ValueError, tee, [], -1)
|
|
for n in xrange(5):
|
|
result = tee('abc', n)
|
|
self.assertEqual(type(result), tuple)
|
|
self.assertEqual(len(result), n)
|
|
self.assertEqual(map(list, result), [list('abc')]*n)
|
|
|
|
# tee pass-through to copyable iterator
|
|
a, b = tee('abc')
|
|
c, d = tee(a)
|
|
self.assert_(a is c)
|
|
|
|
# test tee_new
|
|
t1, t2 = tee('abc')
|
|
tnew = type(t1)
|
|
self.assertRaises(TypeError, tnew)
|
|
self.assertRaises(TypeError, tnew, 10)
|
|
t3 = tnew(t1)
|
|
self.assert_(list(t1) == list(t2) == list(t3) == list('abc'))
|
|
|
|
# test that tee objects are weak referencable
|
|
a, b = tee(xrange(10))
|
|
p = proxy(a)
|
|
self.assertEqual(getattr(p, '__class__'), type(b))
|
|
del a
|
|
self.assertRaises(ReferenceError, getattr, p, '__class__')
|
|
|
|
def test_StopIteration(self):
|
|
self.assertRaises(StopIteration, izip().next)
|
|
|
|
for f in (chain, cycle, izip, groupby):
|
|
self.assertRaises(StopIteration, f([]).next)
|
|
self.assertRaises(StopIteration, f(StopNow()).next)
|
|
|
|
self.assertRaises(StopIteration, islice([], None).next)
|
|
self.assertRaises(StopIteration, islice(StopNow(), None).next)
|
|
|
|
p, q = tee([])
|
|
self.assertRaises(StopIteration, p.next)
|
|
self.assertRaises(StopIteration, q.next)
|
|
p, q = tee(StopNow())
|
|
self.assertRaises(StopIteration, p.next)
|
|
self.assertRaises(StopIteration, q.next)
|
|
|
|
self.assertRaises(StopIteration, repeat(None, 0).next)
|
|
|
|
for f in (ifilter, ifilterfalse, imap, takewhile, dropwhile, starmap):
|
|
self.assertRaises(StopIteration, f(lambda x:x, []).next)
|
|
self.assertRaises(StopIteration, f(lambda x:x, StopNow()).next)
|
|
|
|
class TestGC(unittest.TestCase):
|
|
|
|
def makecycle(self, iterator, container):
|
|
container.append(iterator)
|
|
iterator.next()
|
|
del container, iterator
|
|
|
|
def test_chain(self):
|
|
a = []
|
|
self.makecycle(chain(a), a)
|
|
|
|
def test_cycle(self):
|
|
a = []
|
|
self.makecycle(cycle([a]*2), a)
|
|
|
|
def test_dropwhile(self):
|
|
a = []
|
|
self.makecycle(dropwhile(bool, [0, a, a]), a)
|
|
|
|
def test_groupby(self):
|
|
a = []
|
|
self.makecycle(groupby([a]*2, lambda x:x), a)
|
|
|
|
def test_ifilter(self):
|
|
a = []
|
|
self.makecycle(ifilter(lambda x:True, [a]*2), a)
|
|
|
|
def test_ifilterfalse(self):
|
|
a = []
|
|
self.makecycle(ifilterfalse(lambda x:False, a), a)
|
|
|
|
def test_izip(self):
|
|
a = []
|
|
self.makecycle(izip([a]*2, [a]*3), a)
|
|
|
|
def test_imap(self):
|
|
a = []
|
|
self.makecycle(imap(lambda x:x, [a]*2), a)
|
|
|
|
def test_islice(self):
|
|
a = []
|
|
self.makecycle(islice([a]*2, None), a)
|
|
|
|
def test_repeat(self):
|
|
a = []
|
|
self.makecycle(repeat(a), a)
|
|
|
|
def test_starmap(self):
|
|
a = []
|
|
self.makecycle(starmap(lambda *t: t, [(a,a)]*2), a)
|
|
|
|
def test_takewhile(self):
|
|
a = []
|
|
self.makecycle(takewhile(bool, [1, 0, a, a]), a)
|
|
|
|
def R(seqn):
|
|
'Regular generator'
|
|
for i in seqn:
|
|
yield i
|
|
|
|
class G:
|
|
'Sequence using __getitem__'
|
|
def __init__(self, seqn):
|
|
self.seqn = seqn
|
|
def __getitem__(self, i):
|
|
return self.seqn[i]
|
|
|
|
class I:
|
|
'Sequence using iterator protocol'
|
|
def __init__(self, seqn):
|
|
self.seqn = seqn
|
|
self.i = 0
|
|
def __iter__(self):
|
|
return self
|
|
def next(self):
|
|
if self.i >= len(self.seqn): raise StopIteration
|
|
v = self.seqn[self.i]
|
|
self.i += 1
|
|
return v
|
|
|
|
class Ig:
|
|
'Sequence using iterator protocol defined with a generator'
|
|
def __init__(self, seqn):
|
|
self.seqn = seqn
|
|
self.i = 0
|
|
def __iter__(self):
|
|
for val in self.seqn:
|
|
yield val
|
|
|
|
class X:
|
|
'Missing __getitem__ and __iter__'
|
|
def __init__(self, seqn):
|
|
self.seqn = seqn
|
|
self.i = 0
|
|
def next(self):
|
|
if self.i >= len(self.seqn): raise StopIteration
|
|
v = self.seqn[self.i]
|
|
self.i += 1
|
|
return v
|
|
|
|
class N:
|
|
'Iterator missing next()'
|
|
def __init__(self, seqn):
|
|
self.seqn = seqn
|
|
self.i = 0
|
|
def __iter__(self):
|
|
return self
|
|
|
|
class E:
|
|
'Test propagation of exceptions'
|
|
def __init__(self, seqn):
|
|
self.seqn = seqn
|
|
self.i = 0
|
|
def __iter__(self):
|
|
return self
|
|
def next(self):
|
|
3 // 0
|
|
|
|
class S:
|
|
'Test immediate stop'
|
|
def __init__(self, seqn):
|
|
pass
|
|
def __iter__(self):
|
|
return self
|
|
def next(self):
|
|
raise StopIteration
|
|
|
|
def L(seqn):
|
|
'Test multiple tiers of iterators'
|
|
return chain(imap(lambda x:x, R(Ig(G(seqn)))))
|
|
|
|
|
|
class TestVariousIteratorArgs(unittest.TestCase):
|
|
|
|
def test_chain(self):
|
|
for s in ("123", "", range(1000), ('do', 1.2), xrange(2000,2200,5)):
|
|
for g in (G, I, Ig, S, L, R):
|
|
self.assertEqual(list(chain(g(s))), list(g(s)))
|
|
self.assertEqual(list(chain(g(s), g(s))), list(g(s))+list(g(s)))
|
|
self.assertRaises(TypeError, list, chain(X(s)))
|
|
self.assertRaises(TypeError, list, chain(N(s)))
|
|
self.assertRaises(ZeroDivisionError, list, chain(E(s)))
|
|
|
|
def test_product(self):
|
|
for s in ("123", "", range(1000), ('do', 1.2), xrange(2000,2200,5)):
|
|
self.assertRaises(TypeError, product, X(s))
|
|
self.assertRaises(TypeError, product, N(s))
|
|
self.assertRaises(ZeroDivisionError, product, E(s))
|
|
|
|
def test_cycle(self):
|
|
for s in ("123", "", range(1000), ('do', 1.2), xrange(2000,2200,5)):
|
|
for g in (G, I, Ig, S, L, R):
|
|
tgtlen = len(s) * 3
|
|
expected = list(g(s))*3
|
|
actual = list(islice(cycle(g(s)), tgtlen))
|
|
self.assertEqual(actual, expected)
|
|
self.assertRaises(TypeError, cycle, X(s))
|
|
self.assertRaises(TypeError, list, cycle(N(s)))
|
|
self.assertRaises(ZeroDivisionError, list, cycle(E(s)))
|
|
|
|
def test_groupby(self):
|
|
for s in (range(10), range(0), range(1000), (7,11), xrange(2000,2200,5)):
|
|
for g in (G, I, Ig, S, L, R):
|
|
self.assertEqual([k for k, sb in groupby(g(s))], list(g(s)))
|
|
self.assertRaises(TypeError, groupby, X(s))
|
|
self.assertRaises(TypeError, list, groupby(N(s)))
|
|
self.assertRaises(ZeroDivisionError, list, groupby(E(s)))
|
|
|
|
def test_ifilter(self):
|
|
for s in (range(10), range(0), range(1000), (7,11), xrange(2000,2200,5)):
|
|
for g in (G, I, Ig, S, L, R):
|
|
self.assertEqual(list(ifilter(isEven, g(s))), filter(isEven, g(s)))
|
|
self.assertRaises(TypeError, ifilter, isEven, X(s))
|
|
self.assertRaises(TypeError, list, ifilter(isEven, N(s)))
|
|
self.assertRaises(ZeroDivisionError, list, ifilter(isEven, E(s)))
|
|
|
|
def test_ifilterfalse(self):
|
|
for s in (range(10), range(0), range(1000), (7,11), xrange(2000,2200,5)):
|
|
for g in (G, I, Ig, S, L, R):
|
|
self.assertEqual(list(ifilterfalse(isEven, g(s))), filter(isOdd, g(s)))
|
|
self.assertRaises(TypeError, ifilterfalse, isEven, X(s))
|
|
self.assertRaises(TypeError, list, ifilterfalse(isEven, N(s)))
|
|
self.assertRaises(ZeroDivisionError, list, ifilterfalse(isEven, E(s)))
|
|
|
|
def test_izip(self):
|
|
for s in ("123", "", range(1000), ('do', 1.2), xrange(2000,2200,5)):
|
|
for g in (G, I, Ig, S, L, R):
|
|
self.assertEqual(list(izip(g(s))), zip(g(s)))
|
|
self.assertEqual(list(izip(g(s), g(s))), zip(g(s), g(s)))
|
|
self.assertRaises(TypeError, izip, X(s))
|
|
self.assertRaises(TypeError, list, izip(N(s)))
|
|
self.assertRaises(ZeroDivisionError, list, izip(E(s)))
|
|
|
|
def test_iziplongest(self):
|
|
for s in ("123", "", range(1000), ('do', 1.2), xrange(2000,2200,5)):
|
|
for g in (G, I, Ig, S, L, R):
|
|
self.assertEqual(list(izip_longest(g(s))), zip(g(s)))
|
|
self.assertEqual(list(izip_longest(g(s), g(s))), zip(g(s), g(s)))
|
|
self.assertRaises(TypeError, izip_longest, X(s))
|
|
self.assertRaises(TypeError, list, izip_longest(N(s)))
|
|
self.assertRaises(ZeroDivisionError, list, izip_longest(E(s)))
|
|
|
|
def test_imap(self):
|
|
for s in (range(10), range(0), range(100), (7,11), xrange(20,50,5)):
|
|
for g in (G, I, Ig, S, L, R):
|
|
self.assertEqual(list(imap(onearg, g(s))), map(onearg, g(s)))
|
|
self.assertEqual(list(imap(operator.pow, g(s), g(s))), map(operator.pow, g(s), g(s)))
|
|
self.assertRaises(TypeError, imap, onearg, X(s))
|
|
self.assertRaises(TypeError, list, imap(onearg, N(s)))
|
|
self.assertRaises(ZeroDivisionError, list, imap(onearg, E(s)))
|
|
|
|
def test_islice(self):
|
|
for s in ("12345", "", range(1000), ('do', 1.2), xrange(2000,2200,5)):
|
|
for g in (G, I, Ig, S, L, R):
|
|
self.assertEqual(list(islice(g(s),1,None,2)), list(g(s))[1::2])
|
|
self.assertRaises(TypeError, islice, X(s), 10)
|
|
self.assertRaises(TypeError, list, islice(N(s), 10))
|
|
self.assertRaises(ZeroDivisionError, list, islice(E(s), 10))
|
|
|
|
def test_starmap(self):
|
|
for s in (range(10), range(0), range(100), (7,11), xrange(20,50,5)):
|
|
for g in (G, I, Ig, S, L, R):
|
|
ss = zip(s, s)
|
|
self.assertEqual(list(starmap(operator.pow, g(ss))), map(operator.pow, g(s), g(s)))
|
|
self.assertRaises(TypeError, starmap, operator.pow, X(ss))
|
|
self.assertRaises(TypeError, list, starmap(operator.pow, N(ss)))
|
|
self.assertRaises(ZeroDivisionError, list, starmap(operator.pow, E(ss)))
|
|
|
|
def test_takewhile(self):
|
|
for s in (range(10), range(0), range(1000), (7,11), xrange(2000,2200,5)):
|
|
for g in (G, I, Ig, S, L, R):
|
|
tgt = []
|
|
for elem in g(s):
|
|
if not isEven(elem): break
|
|
tgt.append(elem)
|
|
self.assertEqual(list(takewhile(isEven, g(s))), tgt)
|
|
self.assertRaises(TypeError, takewhile, isEven, X(s))
|
|
self.assertRaises(TypeError, list, takewhile(isEven, N(s)))
|
|
self.assertRaises(ZeroDivisionError, list, takewhile(isEven, E(s)))
|
|
|
|
def test_dropwhile(self):
|
|
for s in (range(10), range(0), range(1000), (7,11), xrange(2000,2200,5)):
|
|
for g in (G, I, Ig, S, L, R):
|
|
tgt = []
|
|
for elem in g(s):
|
|
if not tgt and isOdd(elem): continue
|
|
tgt.append(elem)
|
|
self.assertEqual(list(dropwhile(isOdd, g(s))), tgt)
|
|
self.assertRaises(TypeError, dropwhile, isOdd, X(s))
|
|
self.assertRaises(TypeError, list, dropwhile(isOdd, N(s)))
|
|
self.assertRaises(ZeroDivisionError, list, dropwhile(isOdd, E(s)))
|
|
|
|
def test_tee(self):
|
|
for s in ("123", "", range(1000), ('do', 1.2), xrange(2000,2200,5)):
|
|
for g in (G, I, Ig, S, L, R):
|
|
it1, it2 = tee(g(s))
|
|
self.assertEqual(list(it1), list(g(s)))
|
|
self.assertEqual(list(it2), list(g(s)))
|
|
self.assertRaises(TypeError, tee, X(s))
|
|
self.assertRaises(TypeError, list, tee(N(s))[0])
|
|
self.assertRaises(ZeroDivisionError, list, tee(E(s))[0])
|
|
|
|
class LengthTransparency(unittest.TestCase):
|
|
|
|
def test_repeat(self):
|
|
from test.test_iterlen import len
|
|
self.assertEqual(len(repeat(None, 50)), 50)
|
|
self.assertRaises(TypeError, len, repeat(None))
|
|
|
|
class RegressionTests(unittest.TestCase):
|
|
|
|
def test_sf_793826(self):
|
|
# Fix Armin Rigo's successful efforts to wreak havoc
|
|
|
|
def mutatingtuple(tuple1, f, tuple2):
|
|
# this builds a tuple t which is a copy of tuple1,
|
|
# then calls f(t), then mutates t to be equal to tuple2
|
|
# (needs len(tuple1) == len(tuple2)).
|
|
def g(value, first=[1]):
|
|
if first:
|
|
del first[:]
|
|
f(z.next())
|
|
return value
|
|
items = list(tuple2)
|
|
items[1:1] = list(tuple1)
|
|
gen = imap(g, items)
|
|
z = izip(*[gen]*len(tuple1))
|
|
z.next()
|
|
|
|
def f(t):
|
|
global T
|
|
T = t
|
|
first[:] = list(T)
|
|
|
|
first = []
|
|
mutatingtuple((1,2,3), f, (4,5,6))
|
|
second = list(T)
|
|
self.assertEqual(first, second)
|
|
|
|
|
|
def test_sf_950057(self):
|
|
# Make sure that chain() and cycle() catch exceptions immediately
|
|
# rather than when shifting between input sources
|
|
|
|
def gen1():
|
|
hist.append(0)
|
|
yield 1
|
|
hist.append(1)
|
|
raise AssertionError
|
|
hist.append(2)
|
|
|
|
def gen2(x):
|
|
hist.append(3)
|
|
yield 2
|
|
hist.append(4)
|
|
if x:
|
|
raise StopIteration
|
|
|
|
hist = []
|
|
self.assertRaises(AssertionError, list, chain(gen1(), gen2(False)))
|
|
self.assertEqual(hist, [0,1])
|
|
|
|
hist = []
|
|
self.assertRaises(AssertionError, list, chain(gen1(), gen2(True)))
|
|
self.assertEqual(hist, [0,1])
|
|
|
|
hist = []
|
|
self.assertRaises(AssertionError, list, cycle(gen1()))
|
|
self.assertEqual(hist, [0,1])
|
|
|
|
class SubclassWithKwargsTest(unittest.TestCase):
|
|
def test_keywords_in_subclass(self):
|
|
# count is not subclassable...
|
|
for cls in (repeat, izip, ifilter, ifilterfalse, chain, imap,
|
|
starmap, islice, takewhile, dropwhile, cycle):
|
|
class Subclass(cls):
|
|
def __init__(self, newarg=None, *args):
|
|
cls.__init__(self, *args)
|
|
try:
|
|
Subclass(newarg=1)
|
|
except TypeError, err:
|
|
# we expect type errors because of wrong argument count
|
|
self.failIf("does not take keyword arguments" in err.args[0])
|
|
|
|
|
|
libreftest = """ Doctest for examples in the library reference: libitertools.tex
|
|
|
|
|
|
>>> amounts = [120.15, 764.05, 823.14]
|
|
>>> for checknum, amount in izip(count(1200), amounts):
|
|
... print 'Check %d is for $%.2f' % (checknum, amount)
|
|
...
|
|
Check 1200 is for $120.15
|
|
Check 1201 is for $764.05
|
|
Check 1202 is for $823.14
|
|
|
|
>>> import operator
|
|
>>> for cube in imap(operator.pow, xrange(1,4), repeat(3)):
|
|
... print cube
|
|
...
|
|
1
|
|
8
|
|
27
|
|
|
|
>>> reportlines = ['EuroPython', 'Roster', '', 'alex', '', 'laura', '', 'martin', '', 'walter', '', 'samuele']
|
|
>>> for name in islice(reportlines, 3, None, 2):
|
|
... print name.title()
|
|
...
|
|
Alex
|
|
Laura
|
|
Martin
|
|
Walter
|
|
Samuele
|
|
|
|
>>> from operator import itemgetter
|
|
>>> d = dict(a=1, b=2, c=1, d=2, e=1, f=2, g=3)
|
|
>>> di = sorted(sorted(d.iteritems()), key=itemgetter(1))
|
|
>>> for k, g in groupby(di, itemgetter(1)):
|
|
... print k, map(itemgetter(0), g)
|
|
...
|
|
1 ['a', 'c', 'e']
|
|
2 ['b', 'd', 'f']
|
|
3 ['g']
|
|
|
|
# Find runs of consecutive numbers using groupby. The key to the solution
|
|
# is differencing with a range so that consecutive numbers all appear in
|
|
# same group.
|
|
>>> data = [ 1, 4,5,6, 10, 15,16,17,18, 22, 25,26,27,28]
|
|
>>> for k, g in groupby(enumerate(data), lambda (i,x):i-x):
|
|
... print map(operator.itemgetter(1), g)
|
|
...
|
|
[1]
|
|
[4, 5, 6]
|
|
[10]
|
|
[15, 16, 17, 18]
|
|
[22]
|
|
[25, 26, 27, 28]
|
|
|
|
>>> def take(n, seq):
|
|
... return list(islice(seq, n))
|
|
|
|
>>> def enumerate(iterable):
|
|
... return izip(count(), iterable)
|
|
|
|
>>> def tabulate(function):
|
|
... "Return function(0), function(1), ..."
|
|
... return imap(function, count())
|
|
|
|
>>> def iteritems(mapping):
|
|
... return izip(mapping.iterkeys(), mapping.itervalues())
|
|
|
|
>>> def nth(iterable, n):
|
|
... "Returns the nth item"
|
|
... return list(islice(iterable, n, n+1))
|
|
|
|
>>> def all(seq, pred=None):
|
|
... "Returns True if pred(x) is true for every element in the iterable"
|
|
... for elem in ifilterfalse(pred, seq):
|
|
... return False
|
|
... return True
|
|
|
|
>>> def any(seq, pred=None):
|
|
... "Returns True if pred(x) is true for at least one element in the iterable"
|
|
... for elem in ifilter(pred, seq):
|
|
... return True
|
|
... return False
|
|
|
|
>>> def no(seq, pred=None):
|
|
... "Returns True if pred(x) is false for every element in the iterable"
|
|
... for elem in ifilter(pred, seq):
|
|
... return False
|
|
... return True
|
|
|
|
>>> def quantify(seq, pred=None):
|
|
... "Count how many times the predicate is true in the sequence"
|
|
... return sum(imap(pred, seq))
|
|
|
|
>>> def padnone(seq):
|
|
... "Returns the sequence elements and then returns None indefinitely"
|
|
... return chain(seq, repeat(None))
|
|
|
|
>>> def ncycles(seq, n):
|
|
... "Returns the sequence elements n times"
|
|
... return chain(*repeat(seq, n))
|
|
|
|
>>> def dotproduct(vec1, vec2):
|
|
... return sum(imap(operator.mul, vec1, vec2))
|
|
|
|
>>> def flatten(listOfLists):
|
|
... return list(chain(*listOfLists))
|
|
|
|
>>> def repeatfunc(func, times=None, *args):
|
|
... "Repeat calls to func with specified arguments."
|
|
... " Example: repeatfunc(random.random)"
|
|
... if times is None:
|
|
... return starmap(func, repeat(args))
|
|
... else:
|
|
... return starmap(func, repeat(args, times))
|
|
|
|
>>> def pairwise(iterable):
|
|
... "s -> (s0,s1), (s1,s2), (s2, s3), ..."
|
|
... a, b = tee(iterable)
|
|
... try:
|
|
... b.next()
|
|
... except StopIteration:
|
|
... pass
|
|
... return izip(a, b)
|
|
|
|
This is not part of the examples but it tests to make sure the definitions
|
|
perform as purported.
|
|
|
|
>>> take(10, count())
|
|
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
|
|
|
|
>>> list(enumerate('abc'))
|
|
[(0, 'a'), (1, 'b'), (2, 'c')]
|
|
|
|
>>> list(islice(tabulate(lambda x: 2*x), 4))
|
|
[0, 2, 4, 6]
|
|
|
|
>>> nth('abcde', 3)
|
|
['d']
|
|
|
|
>>> all([2, 4, 6, 8], lambda x: x%2==0)
|
|
True
|
|
|
|
>>> all([2, 3, 6, 8], lambda x: x%2==0)
|
|
False
|
|
|
|
>>> any([2, 4, 6, 8], lambda x: x%2==0)
|
|
True
|
|
|
|
>>> any([1, 3, 5, 9], lambda x: x%2==0,)
|
|
False
|
|
|
|
>>> no([1, 3, 5, 9], lambda x: x%2==0)
|
|
True
|
|
|
|
>>> no([1, 2, 5, 9], lambda x: x%2==0)
|
|
False
|
|
|
|
>>> quantify(xrange(99), lambda x: x%2==0)
|
|
50
|
|
|
|
>>> a = [[1, 2, 3], [4, 5, 6]]
|
|
>>> flatten(a)
|
|
[1, 2, 3, 4, 5, 6]
|
|
|
|
>>> list(repeatfunc(pow, 5, 2, 3))
|
|
[8, 8, 8, 8, 8]
|
|
|
|
>>> import random
|
|
>>> take(5, imap(int, repeatfunc(random.random)))
|
|
[0, 0, 0, 0, 0]
|
|
|
|
>>> list(pairwise('abcd'))
|
|
[('a', 'b'), ('b', 'c'), ('c', 'd')]
|
|
|
|
>>> list(pairwise([]))
|
|
[]
|
|
|
|
>>> list(pairwise('a'))
|
|
[]
|
|
|
|
>>> list(islice(padnone('abc'), 0, 6))
|
|
['a', 'b', 'c', None, None, None]
|
|
|
|
>>> list(ncycles('abc', 3))
|
|
['a', 'b', 'c', 'a', 'b', 'c', 'a', 'b', 'c']
|
|
|
|
>>> dotproduct([1,2,3], [4,5,6])
|
|
32
|
|
|
|
"""
|
|
|
|
__test__ = {'libreftest' : libreftest}
|
|
|
|
def test_main(verbose=None):
|
|
test_classes = (TestBasicOps, TestVariousIteratorArgs, TestGC,
|
|
RegressionTests, LengthTransparency,
|
|
SubclassWithKwargsTest)
|
|
test_support.run_unittest(*test_classes)
|
|
|
|
# verify reference counting
|
|
if verbose and hasattr(sys, "gettotalrefcount"):
|
|
import gc
|
|
counts = [None] * 5
|
|
for i in xrange(len(counts)):
|
|
test_support.run_unittest(*test_classes)
|
|
gc.collect()
|
|
counts[i] = sys.gettotalrefcount()
|
|
print counts
|
|
|
|
# doctest the examples in the library reference
|
|
test_support.run_doctest(sys.modules[__name__], verbose)
|
|
|
|
if __name__ == "__main__":
|
|
test_main(verbose=True)
|