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2537 lines (2205 loc) · 104 KB
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import doctest
import unittest
from test import support
from test.support import threading_helper
from itertools import *
import weakref
from decimal import Decimal
from fractions import Fraction
import operator
import random
import copy
import pickle
from functools import reduce
import sys
import struct
import threading
import gc
import warnings
def pickle_deprecated(testfunc):
""" Run the test three times.
First, verify that a Deprecation Warning is raised.
Second, run normally but with DeprecationWarnings temporarily disabled.
Third, run with warnings promoted to errors.
"""
def inner(self):
with self.assertWarns(DeprecationWarning):
testfunc(self)
with warnings.catch_warnings():
warnings.simplefilter("ignore", category=DeprecationWarning)
testfunc(self)
with warnings.catch_warnings():
warnings.simplefilter("error", category=DeprecationWarning)
with self.assertRaises((DeprecationWarning, AssertionError, SystemError)):
testfunc(self)
return inner
maxsize = support.MAX_Py_ssize_t
minsize = -maxsize-1
def lzip(*args):
return list(zip(*args))
def onearg(x):
'Test function of one argument'
return 2*x
def errfunc(*args):
'Test function that raises an error'
raise ValueError
def gen3():
'Non-restartable source sequence'
for i in (0, 1, 2):
yield i
def isEven(x):
'Test predicate'
return x%2==0
def isOdd(x):
'Test predicate'
return x%2==1
def tupleize(*args):
return args
def irange(n):
for i in range(n):
yield i
class StopNow:
'Class emulating an empty iterable.'
def __iter__(self):
return self
def __next__(self):
raise StopIteration
def take(n, seq):
'Convenience function for partially consuming a long of infinite iterable'
return list(islice(seq, n))
def prod(iterable):
return reduce(operator.mul, iterable, 1)
def fact(n):
'Factorial'
return prod(range(1, n+1))
# root level methods for pickling ability
def testR(r):
return r[0]
def testR2(r):
return r[2]
def underten(x):
return x<10
picklecopiers = [lambda s, proto=proto: pickle.loads(pickle.dumps(s, proto))
for proto in range(pickle.HIGHEST_PROTOCOL + 1)]
class TestBasicOps(unittest.TestCase):
def pickletest(self, protocol, it, stop=4, take=1, compare=None):
"""Test that an iterator is the same after pickling, also when part-consumed"""
def expand(it, i=0):
# Recursively expand iterables, within sensible bounds
if i > 10:
raise RuntimeError("infinite recursion encountered")
if isinstance(it, str):
return it
try:
l = list(islice(it, stop))
except TypeError:
return it # can't expand it
return [expand(e, i+1) for e in l]
# Test the initial copy against the original
dump = pickle.dumps(it, protocol)
i2 = pickle.loads(dump)
self.assertEqual(type(it), type(i2))
a, b = expand(it), expand(i2)
self.assertEqual(a, b)
if compare:
c = expand(compare)
self.assertEqual(a, c)
# Take from the copy, and create another copy and compare them.
i3 = pickle.loads(dump)
took = 0
try:
for i in range(take):
next(i3)
took += 1
except StopIteration:
pass #in case there is less data than 'take'
dump = pickle.dumps(i3, protocol)
i4 = pickle.loads(dump)
a, b = expand(i3), expand(i4)
self.assertEqual(a, b)
if compare:
c = expand(compare[took:])
self.assertEqual(a, c);
@pickle_deprecated
def test_accumulate(self):
self.assertEqual(list(accumulate(range(10))), # one positional arg
[0, 1, 3, 6, 10, 15, 21, 28, 36, 45])
self.assertEqual(list(accumulate(iterable=range(10))), # kw arg
[0, 1, 3, 6, 10, 15, 21, 28, 36, 45])
for typ in int, complex, Decimal, Fraction: # multiple types
self.assertEqual(
list(accumulate(map(typ, range(10)))),
list(map(typ, [0, 1, 3, 6, 10, 15, 21, 28, 36, 45])))
self.assertEqual(list(accumulate('abc')), ['a', 'ab', 'abc']) # works with non-numeric
self.assertEqual(list(accumulate([])), []) # empty iterable
self.assertEqual(list(accumulate([7])), [7]) # iterable of length one
self.assertRaises(TypeError, accumulate, range(10), 5, 6) # too many args
self.assertRaises(TypeError, accumulate) # too few args
self.assertRaises(TypeError, accumulate, x=range(10)) # unexpected kwd arg
self.assertRaises(TypeError, list, accumulate([1, []])) # args that don't add
s = [2, 8, 9, 5, 7, 0, 3, 4, 1, 6]
self.assertEqual(list(accumulate(s, min)),
[2, 2, 2, 2, 2, 0, 0, 0, 0, 0])
self.assertEqual(list(accumulate(s, max)),
[2, 8, 9, 9, 9, 9, 9, 9, 9, 9])
self.assertEqual(list(accumulate(s, operator.mul)),
[2, 16, 144, 720, 5040, 0, 0, 0, 0, 0])
with self.assertRaises(TypeError):
list(accumulate(s, chr)) # unary-operation
for proto in range(pickle.HIGHEST_PROTOCOL + 1):
self.pickletest(proto, accumulate(range(10))) # test pickling
self.pickletest(proto, accumulate(range(10), initial=7))
self.assertEqual(list(accumulate([10, 5, 1], initial=None)), [10, 15, 16])
self.assertEqual(list(accumulate([10, 5, 1], initial=100)), [100, 110, 115, 116])
self.assertEqual(list(accumulate([], initial=100)), [100])
with self.assertRaises(TypeError):
list(accumulate([10, 20], 100))
def test_batched(self):
self.assertEqual(list(batched('ABCDEFG', 3)),
[('A', 'B', 'C'), ('D', 'E', 'F'), ('G',)])
self.assertEqual(list(batched('ABCDEFG', 2)),
[('A', 'B'), ('C', 'D'), ('E', 'F'), ('G',)])
self.assertEqual(list(batched('ABCDEFG', 1)),
[('A',), ('B',), ('C',), ('D',), ('E',), ('F',), ('G',)])
with self.assertRaises(TypeError): # Too few arguments
list(batched('ABCDEFG'))
with self.assertRaises(TypeError):
list(batched('ABCDEFG', 3, None)) # Too many arguments
with self.assertRaises(TypeError):
list(batched(None, 3)) # Non-iterable input
with self.assertRaises(TypeError):
list(batched('ABCDEFG', 'hello')) # n is a string
with self.assertRaises(ValueError):
list(batched('ABCDEFG', 0)) # n is zero
with self.assertRaises(ValueError):
list(batched('ABCDEFG', -1)) # n is negative
data = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
for n in range(1, 6):
for i in range(len(data)):
s = data[:i]
batches = list(batched(s, n))
with self.subTest(s=s, n=n, batches=batches):
# Order is preserved and no data is lost
self.assertEqual(''.join(chain(*batches)), s)
# Each batch is an exact tuple
self.assertTrue(all(type(batch) is tuple for batch in batches))
# All but the last batch is of size n
if batches:
last_batch = batches.pop()
self.assertTrue(all(len(batch) == n for batch in batches))
self.assertTrue(len(last_batch) <= n)
batches.append(last_batch)
def test_chain(self):
def chain2(*iterables):
'Pure python version in the docs'
for it in iterables:
for element in it:
yield element
for c in (chain, chain2):
self.assertEqual(list(c('abc', 'def')), list('abcdef'))
self.assertEqual(list(c('abc')), list('abc'))
self.assertEqual(list(c('')), [])
self.assertEqual(take(4, c('abc', 'def')), list('abcd'))
self.assertRaises(TypeError, list,c(2, 3))
def test_chain_from_iterable(self):
self.assertEqual(list(chain.from_iterable(['abc', 'def'])), list('abcdef'))
self.assertEqual(list(chain.from_iterable(['abc'])), list('abc'))
self.assertEqual(list(chain.from_iterable([''])), [])
self.assertEqual(take(4, chain.from_iterable(['abc', 'def'])), list('abcd'))
self.assertRaises(TypeError, list, chain.from_iterable([2, 3]))
self.assertEqual(list(islice(chain.from_iterable(repeat(range(5))), 2)), [0, 1])
@pickle_deprecated
def test_chain_reducible(self):
for oper in [copy.deepcopy] + picklecopiers:
it = chain('abc', 'def')
self.assertEqual(list(oper(it)), list('abcdef'))
self.assertEqual(next(it), 'a')
self.assertEqual(list(oper(it)), list('bcdef'))
self.assertEqual(list(oper(chain(''))), [])
self.assertEqual(take(4, oper(chain('abc', 'def'))), list('abcd'))
self.assertRaises(TypeError, list, oper(chain(2, 3)))
for proto in range(pickle.HIGHEST_PROTOCOL + 1):
self.pickletest(proto, chain('abc', 'def'), compare=list('abcdef'))
@pickle_deprecated
def test_chain_setstate(self):
self.assertRaises(TypeError, chain().__setstate__, ())
self.assertRaises(TypeError, chain().__setstate__, [])
self.assertRaises(TypeError, chain().__setstate__, 0)
self.assertRaises(TypeError, chain().__setstate__, ([],))
self.assertRaises(TypeError, chain().__setstate__, (iter([]), []))
it = chain()
it.__setstate__((iter(['abc', 'def']),))
self.assertEqual(list(it), ['a', 'b', 'c', 'd', 'e', 'f'])
it = chain()
it.__setstate__((iter(['abc', 'def']), iter(['ghi'])))
self.assertEqual(list(it), ['ghi', 'a', 'b', 'c', 'd', 'e', 'f'])
@pickle_deprecated
def test_combinations(self):
self.assertRaises(TypeError, combinations, 'abc') # missing r argument
self.assertRaises(TypeError, combinations, 'abc', 2, 1) # too many arguments
self.assertRaises(TypeError, combinations, None) # pool is not iterable
self.assertRaises(ValueError, combinations, 'abc', -2) # r is negative
for op in [lambda a:a] + picklecopiers:
self.assertEqual(list(op(combinations('abc', 32))), []) # r > n
self.assertEqual(list(op(combinations('ABCD', 2))),
[('A','B'), ('A','C'), ('A','D'), ('B','C'), ('B','D'), ('C','D')])
testIntermediate = combinations('ABCD', 2)
next(testIntermediate)
self.assertEqual(list(op(testIntermediate)),
[('A','C'), ('A','D'), ('B','C'), ('B','D'), ('C','D')])
self.assertEqual(list(op(combinations(range(4), 3))),
[(0,1,2), (0,1,3), (0,2,3), (1,2,3)])
testIntermediate = combinations(range(4), 3)
next(testIntermediate)
self.assertEqual(list(op(testIntermediate)),
[(0,1,3), (0,2,3), (1,2,3)])
def combinations1(iterable, r):
'Pure python version shown in the docs'
pool = tuple(iterable)
n = len(pool)
if r > n:
return
indices = list(range(r))
yield tuple(pool[i] for i in indices)
while 1:
for i in reversed(range(r)):
if indices[i] != i + n - r:
break
else:
return
indices[i] += 1
for j in range(i+1, r):
indices[j] = indices[j-1] + 1
yield tuple(pool[i] for i in indices)
def combinations2(iterable, r):
'Pure python version shown in the docs'
pool = tuple(iterable)
n = len(pool)
for indices in permutations(range(n), r):
if sorted(indices) == list(indices):
yield tuple(pool[i] for i in indices)
def combinations3(iterable, r):
'Pure python version from cwr()'
pool = tuple(iterable)
n = len(pool)
for indices in combinations_with_replacement(range(n), r):
if len(set(indices)) == r:
yield tuple(pool[i] for i in indices)
for n in range(7):
values = [5*x-12 for x in range(n)]
for r in range(n+2):
result = list(combinations(values, r))
self.assertEqual(len(result), 0 if r>n else fact(n) / fact(r) / fact(n-r)) # right number of combs
self.assertEqual(len(result), len(set(result))) # no repeats
self.assertEqual(result, sorted(result)) # lexicographic order
for c in result:
self.assertEqual(len(c), r) # r-length combinations
self.assertEqual(len(set(c)), r) # no duplicate elements
self.assertEqual(list(c), sorted(c)) # keep original ordering
self.assertTrue(all(e in values for e in c)) # elements taken from input iterable
self.assertEqual(list(c),
[e for e in values if e in c]) # comb is a subsequence of the input iterable
self.assertEqual(result, list(combinations1(values, r))) # matches first pure python version
self.assertEqual(result, list(combinations2(values, r))) # matches second pure python version
self.assertEqual(result, list(combinations3(values, r))) # matches second pure python version
for proto in range(pickle.HIGHEST_PROTOCOL + 1):
self.pickletest(proto, combinations(values, r)) # test pickling
@support.bigaddrspacetest
def test_combinations_overflow(self):
with self.assertRaises((OverflowError, MemoryError)):
combinations("AA", 2**29)
# Test implementation detail: tuple re-use
@support.impl_detail("tuple reuse is specific to CPython")
def test_combinations_tuple_reuse(self):
self.assertEqual(len(set(map(id, combinations('abcde', 3)))), 1)
self.assertNotEqual(len(set(map(id, list(combinations('abcde', 3))))), 1)
@pickle_deprecated
def test_combinations_with_replacement(self):
cwr = combinations_with_replacement
self.assertRaises(TypeError, cwr, 'abc') # missing r argument
self.assertRaises(TypeError, cwr, 'abc', 2, 1) # too many arguments
self.assertRaises(TypeError, cwr, None) # pool is not iterable
self.assertRaises(ValueError, cwr, 'abc', -2) # r is negative
for op in [lambda a:a] + picklecopiers:
self.assertEqual(list(op(cwr('ABC', 2))),
[('A','A'), ('A','B'), ('A','C'), ('B','B'), ('B','C'), ('C','C')])
testIntermediate = cwr('ABC', 2)
next(testIntermediate)
self.assertEqual(list(op(testIntermediate)),
[('A','B'), ('A','C'), ('B','B'), ('B','C'), ('C','C')])
def cwr1(iterable, r):
'Pure python version shown in the docs'
# number items returned: (n+r-1)! / r! / (n-1)! when n>0
pool = tuple(iterable)
n = len(pool)
if not n and r:
return
indices = [0] * r
yield tuple(pool[i] for i in indices)
while 1:
for i in reversed(range(r)):
if indices[i] != n - 1:
break
else:
return
indices[i:] = [indices[i] + 1] * (r - i)
yield tuple(pool[i] for i in indices)
def cwr2(iterable, r):
'Pure python version shown in the docs'
pool = tuple(iterable)
n = len(pool)
for indices in product(range(n), repeat=r):
if sorted(indices) == list(indices):
yield tuple(pool[i] for i in indices)
def numcombs(n, r):
if not n:
return 0 if r else 1
return fact(n+r-1) / fact(r)/ fact(n-1)
for n in range(7):
values = [5*x-12 for x in range(n)]
for r in range(n+2):
result = list(cwr(values, r))
self.assertEqual(len(result), numcombs(n, r)) # right number of combs
self.assertEqual(len(result), len(set(result))) # no repeats
self.assertEqual(result, sorted(result)) # lexicographic order
regular_combs = list(combinations(values, r)) # compare to combs without replacement
if n == 0 or r <= 1:
self.assertEqual(result, regular_combs) # cases that should be identical
else:
self.assertTrue(set(result) >= set(regular_combs)) # rest should be supersets of regular combs
for c in result:
self.assertEqual(len(c), r) # r-length combinations
noruns = [k for k,v in groupby(c)] # combo without consecutive repeats
self.assertEqual(len(noruns), len(set(noruns))) # no repeats other than consecutive
self.assertEqual(list(c), sorted(c)) # keep original ordering
self.assertTrue(all(e in values for e in c)) # elements taken from input iterable
self.assertEqual(noruns,
[e for e in values if e in c]) # comb is a subsequence of the input iterable
self.assertEqual(result, list(cwr1(values, r))) # matches first pure python version
self.assertEqual(result, list(cwr2(values, r))) # matches second pure python version
for proto in range(pickle.HIGHEST_PROTOCOL + 1):
self.pickletest(proto, cwr(values,r)) # test pickling
@support.bigaddrspacetest
def test_combinations_with_replacement_overflow(self):
with self.assertRaises((OverflowError, MemoryError)):
combinations_with_replacement("AA", 2**30)
# Test implementation detail: tuple re-use
@support.impl_detail("tuple reuse is specific to CPython")
def test_combinations_with_replacement_tuple_reuse(self):
cwr = combinations_with_replacement
self.assertEqual(len(set(map(id, cwr('abcde', 3)))), 1)
self.assertNotEqual(len(set(map(id, list(cwr('abcde', 3))))), 1)
@pickle_deprecated
def test_permutations(self):
self.assertRaises(TypeError, permutations) # too few arguments
self.assertRaises(TypeError, permutations, 'abc', 2, 1) # too many arguments
self.assertRaises(TypeError, permutations, None) # pool is not iterable
self.assertRaises(ValueError, permutations, 'abc', -2) # r is negative
self.assertEqual(list(permutations('abc', 32)), []) # r > n
self.assertRaises(TypeError, permutations, 'abc', 's') # r is not an int or None
self.assertEqual(list(permutations(range(3), 2)),
[(0,1), (0,2), (1,0), (1,2), (2,0), (2,1)])
def permutations1(iterable, r=None):
'Pure python version shown in the docs'
pool = tuple(iterable)
n = len(pool)
r = n if r is None else r
if r > n:
return
indices = list(range(n))
cycles = list(range(n-r+1, n+1))[::-1]
yield tuple(pool[i] for i in indices[:r])
while n:
for i in reversed(range(r)):
cycles[i] -= 1
if cycles[i] == 0:
indices[i:] = indices[i+1:] + indices[i:i+1]
cycles[i] = n - i
else:
j = cycles[i]
indices[i], indices[-j] = indices[-j], indices[i]
yield tuple(pool[i] for i in indices[:r])
break
else:
return
def permutations2(iterable, r=None):
'Pure python version shown in the docs'
pool = tuple(iterable)
n = len(pool)
r = n if r is None else r
for indices in product(range(n), repeat=r):
if len(set(indices)) == r:
yield tuple(pool[i] for i in indices)
for n in range(7):
values = [5*x-12 for x in range(n)]
for r in range(n+2):
result = list(permutations(values, r))
self.assertEqual(len(result), 0 if r>n else fact(n) / fact(n-r)) # right number of perms
self.assertEqual(len(result), len(set(result))) # no repeats
self.assertEqual(result, sorted(result)) # lexicographic order
for p in result:
self.assertEqual(len(p), r) # r-length permutations
self.assertEqual(len(set(p)), r) # no duplicate elements
self.assertTrue(all(e in values for e in p)) # elements taken from input iterable
self.assertEqual(result, list(permutations1(values, r))) # matches first pure python version
self.assertEqual(result, list(permutations2(values, r))) # matches second pure python version
if r == n:
self.assertEqual(result, list(permutations(values, None))) # test r as None
self.assertEqual(result, list(permutations(values))) # test default r
for proto in range(pickle.HIGHEST_PROTOCOL + 1):
self.pickletest(proto, permutations(values, r)) # test pickling
@support.bigaddrspacetest
def test_permutations_overflow(self):
with self.assertRaises((OverflowError, MemoryError)):
permutations("A", 2**30)
@support.impl_detail("tuple reuse is specific to CPython")
def test_permutations_tuple_reuse(self):
self.assertEqual(len(set(map(id, permutations('abcde', 3)))), 1)
self.assertNotEqual(len(set(map(id, list(permutations('abcde', 3))))), 1)
def test_combinatorics(self):
# Test relationships between product(), permutations(),
# combinations() and combinations_with_replacement().
for n in range(6):
s = 'ABCDEFG'[:n]
for r in range(8):
prod = list(product(s, repeat=r))
cwr = list(combinations_with_replacement(s, r))
perm = list(permutations(s, r))
comb = list(combinations(s, r))
# Check size
self.assertEqual(len(prod), n**r)
self.assertEqual(len(cwr), (fact(n+r-1) / fact(r)/ fact(n-1)) if n else (not r))
self.assertEqual(len(perm), 0 if r>n else fact(n) / fact(n-r))
self.assertEqual(len(comb), 0 if r>n else fact(n) / fact(r) / fact(n-r))
# Check lexicographic order without repeated tuples
self.assertEqual(prod, sorted(set(prod)))
self.assertEqual(cwr, sorted(set(cwr)))
self.assertEqual(perm, sorted(set(perm)))
self.assertEqual(comb, sorted(set(comb)))
# Check interrelationships
self.assertEqual(cwr, [t for t in prod if sorted(t)==list(t)]) # cwr: prods which are sorted
self.assertEqual(perm, [t for t in prod if len(set(t))==r]) # perm: prods with no dups
self.assertEqual(comb, [t for t in perm if sorted(t)==list(t)]) # comb: perms that are sorted
self.assertEqual(comb, [t for t in cwr if len(set(t))==r]) # comb: cwrs without dups
self.assertEqual(comb, list(filter(set(cwr).__contains__, perm))) # comb: perm that is a cwr
self.assertEqual(comb, list(filter(set(perm).__contains__, cwr))) # comb: cwr that is a perm
self.assertEqual(comb, sorted(set(cwr) & set(perm))) # comb: both a cwr and a perm
@pickle_deprecated
def test_compress(self):
self.assertEqual(list(compress(data='ABCDEF', selectors=[1,0,1,0,1,1])), list('ACEF'))
self.assertEqual(list(compress('ABCDEF', [1,0,1,0,1,1])), list('ACEF'))
self.assertEqual(list(compress('ABCDEF', [0,0,0,0,0,0])), list(''))
self.assertEqual(list(compress('ABCDEF', [1,1,1,1,1,1])), list('ABCDEF'))
self.assertEqual(list(compress('ABCDEF', [1,0,1])), list('AC'))
self.assertEqual(list(compress('ABC', [0,1,1,1,1,1])), list('BC'))
n = 10000
data = chain.from_iterable(repeat(range(6), n))
selectors = chain.from_iterable(repeat((0, 1)))
self.assertEqual(list(compress(data, selectors)), [1,3,5] * n)
self.assertRaises(TypeError, compress, None, range(6)) # 1st arg not iterable
self.assertRaises(TypeError, compress, range(6), None) # 2nd arg not iterable
self.assertRaises(TypeError, compress, range(6)) # too few args
self.assertRaises(TypeError, compress, range(6), None) # too many args
# check copy, deepcopy, pickle
for op in [lambda a:copy.copy(a), lambda a:copy.deepcopy(a)] + picklecopiers:
for data, selectors, result1, result2 in [
('ABCDEF', [1,0,1,0,1,1], 'ACEF', 'CEF'),
('ABCDEF', [0,0,0,0,0,0], '', ''),
('ABCDEF', [1,1,1,1,1,1], 'ABCDEF', 'BCDEF'),
('ABCDEF', [1,0,1], 'AC', 'C'),
('ABC', [0,1,1,1,1,1], 'BC', 'C'),
]:
self.assertEqual(list(op(compress(data=data, selectors=selectors))), list(result1))
self.assertEqual(list(op(compress(data, selectors))), list(result1))
testIntermediate = compress(data, selectors)
if result1:
next(testIntermediate)
self.assertEqual(list(op(testIntermediate)), list(result2))
@pickle_deprecated
def test_count(self):
self.assertEqual(lzip('abc',count()), [('a', 0), ('b', 1), ('c', 2)])
self.assertEqual(lzip('abc',count(3)), [('a', 3), ('b', 4), ('c', 5)])
self.assertEqual(take(2, lzip('abc',count(3))), [('a', 3), ('b', 4)])
self.assertEqual(take(2, zip('abc',count(-1))), [('a', -1), ('b', 0)])
self.assertEqual(take(2, zip('abc',count(-3))), [('a', -3), ('b', -2)])
self.assertRaises(TypeError, count, 2, 3, 4)
self.assertRaises(TypeError, count, 'a')
self.assertEqual(take(10, count(maxsize-5)),
list(range(maxsize-5, maxsize+5)))
self.assertEqual(take(10, count(-maxsize-5)),
list(range(-maxsize-5, -maxsize+5)))
self.assertEqual(take(3, count(3.25)), [3.25, 4.25, 5.25])
self.assertEqual(take(3, count(3.25-4j)), [3.25-4j, 4.25-4j, 5.25-4j])
self.assertEqual(take(3, count(Decimal('1.1'))),
[Decimal('1.1'), Decimal('2.1'), Decimal('3.1')])
self.assertEqual(take(3, count(Fraction(2, 3))),
[Fraction(2, 3), Fraction(5, 3), Fraction(8, 3)])
BIGINT = 1<<1000
self.assertEqual(take(3, count(BIGINT)), [BIGINT, BIGINT+1, BIGINT+2])
c = count(3)
self.assertEqual(repr(c), 'count(3)')
next(c)
self.assertEqual(repr(c), 'count(4)')
c = count(-9)
self.assertEqual(repr(c), 'count(-9)')
next(c)
self.assertEqual(next(c), -8)
self.assertEqual(repr(count(10.25)), 'count(10.25)')
self.assertEqual(repr(count(10.0)), 'count(10.0)')
self.assertEqual(type(next(count(10.0))), float)
for i in (-sys.maxsize-5, -sys.maxsize+5 ,-10, -1, 0, 10, sys.maxsize-5, sys.maxsize+5):
# Test repr
r1 = repr(count(i))
r2 = 'count(%r)'.__mod__(i)
self.assertEqual(r1, r2)
# check copy, deepcopy, pickle
for value in -3, 3, maxsize-5, maxsize+5:
c = count(value)
self.assertEqual(next(copy.copy(c)), value)
self.assertEqual(next(copy.deepcopy(c)), value)
for proto in range(pickle.HIGHEST_PROTOCOL + 1):
self.pickletest(proto, count(value))
#check proper internal error handling for large "step' sizes
count(1, maxsize+5); sys.exc_info()
@pickle_deprecated
def test_count_with_stride(self):
self.assertEqual(lzip('abc',count(2,3)), [('a', 2), ('b', 5), ('c', 8)])
self.assertEqual(lzip('abc',count(start=2,step=3)),
[('a', 2), ('b', 5), ('c', 8)])
self.assertEqual(lzip('abc',count(step=-1)),
[('a', 0), ('b', -1), ('c', -2)])
self.assertRaises(TypeError, count, 'a', 'b')
self.assertEqual(lzip('abc',count(2,0)), [('a', 2), ('b', 2), ('c', 2)])
self.assertEqual(lzip('abc',count(2,1)), [('a', 2), ('b', 3), ('c', 4)])
self.assertEqual(lzip('abc',count(2,3)), [('a', 2), ('b', 5), ('c', 8)])
self.assertEqual(take(20, count(maxsize-15, 3)), take(20, range(maxsize-15, maxsize+100, 3)))
self.assertEqual(take(20, count(-maxsize-15, 3)), take(20, range(-maxsize-15,-maxsize+100, 3)))
self.assertEqual(take(3, count(10, maxsize+5)),
list(range(10, 10+3*(maxsize+5), maxsize+5)))
self.assertEqual(take(3, count(2, 1.25)), [2, 3.25, 4.5])
self.assertEqual(take(3, count(2, 3.25-4j)), [2, 5.25-4j, 8.5-8j])
self.assertEqual(take(3, count(Decimal('1.1'), Decimal('.1'))),
[Decimal('1.1'), Decimal('1.2'), Decimal('1.3')])
self.assertEqual(take(3, count(Fraction(2,3), Fraction(1,7))),
[Fraction(2,3), Fraction(17,21), Fraction(20,21)])
BIGINT = 1<<1000
self.assertEqual(take(3, count(step=BIGINT)), [0, BIGINT, 2*BIGINT])
self.assertEqual(repr(take(3, count(10, 2.5))), repr([10, 12.5, 15.0]))
c = count(3, 5)
self.assertEqual(repr(c), 'count(3, 5)')
next(c)
self.assertEqual(repr(c), 'count(8, 5)')
c = count(-9, 0)
self.assertEqual(repr(c), 'count(-9, 0)')
next(c)
self.assertEqual(repr(c), 'count(-9, 0)')
c = count(-9, -3)
self.assertEqual(repr(c), 'count(-9, -3)')
next(c)
self.assertEqual(repr(c), 'count(-12, -3)')
self.assertEqual(repr(c), 'count(-12, -3)')
self.assertEqual(repr(count(10.5, 1.25)), 'count(10.5, 1.25)')
self.assertEqual(repr(count(10.5, 1)), 'count(10.5)') # suppress step=1 when it's an int
self.assertEqual(repr(count(10.5, 1.00)), 'count(10.5, 1.0)') # do show float values lilke 1.0
self.assertEqual(repr(count(10, 1.00)), 'count(10, 1.0)')
c = count(10, 1.0)
self.assertEqual(type(next(c)), int)
self.assertEqual(type(next(c)), float)
for i in (-sys.maxsize-5, -sys.maxsize+5 ,-10, -1, 0, 10, sys.maxsize-5, sys.maxsize+5):
for j in (-sys.maxsize-5, -sys.maxsize+5 ,-10, -1, 0, 1, 10, sys.maxsize-5, sys.maxsize+5):
# Test repr
r1 = repr(count(i, j))
if j == 1:
r2 = ('count(%r)' % i)
else:
r2 = ('count(%r, %r)' % (i, j))
self.assertEqual(r1, r2)
for proto in range(pickle.HIGHEST_PROTOCOL + 1):
self.pickletest(proto, count(i, j))
def test_cycle(self):
self.assertEqual(take(10, cycle('abc')), list('abcabcabca'))
self.assertEqual(list(cycle('')), [])
self.assertRaises(TypeError, cycle)
self.assertRaises(TypeError, cycle, 5)
self.assertEqual(list(islice(cycle(gen3()),10)), [0,1,2,0,1,2,0,1,2,0])
@pickle_deprecated
def test_cycle_copy_pickle(self):
# check copy, deepcopy, pickle
c = cycle('abc')
self.assertEqual(next(c), 'a')
#simple copy currently not supported, because __reduce__ returns
#an internal iterator
#self.assertEqual(take(10, copy.copy(c)), list('bcabcabcab'))
self.assertEqual(take(10, copy.deepcopy(c)), list('bcabcabcab'))
for proto in range(pickle.HIGHEST_PROTOCOL + 1):
self.assertEqual(take(10, pickle.loads(pickle.dumps(c, proto))),
list('bcabcabcab'))
next(c)
self.assertEqual(take(10, pickle.loads(pickle.dumps(c, proto))),
list('cabcabcabc'))
next(c)
next(c)
for proto in range(pickle.HIGHEST_PROTOCOL + 1):
self.pickletest(proto, cycle('abc'))
for proto in range(pickle.HIGHEST_PROTOCOL + 1):
# test with partial consumed input iterable
it = iter('abcde')
c = cycle(it)
_ = [next(c) for i in range(2)] # consume 2 of 5 inputs
p = pickle.dumps(c, proto)
d = pickle.loads(p) # rebuild the cycle object
self.assertEqual(take(20, d), list('cdeabcdeabcdeabcdeab'))
# test with completely consumed input iterable
it = iter('abcde')
c = cycle(it)
_ = [next(c) for i in range(7)] # consume 7 of 5 inputs
p = pickle.dumps(c, proto)
d = pickle.loads(p) # rebuild the cycle object
self.assertEqual(take(20, d), list('cdeabcdeabcdeabcdeab'))
@pickle_deprecated
def test_cycle_unpickle_compat(self):
testcases = [
b'citertools\ncycle\n(c__builtin__\niter\n((lI1\naI2\naI3\natRI1\nbtR((lI1\naI0\ntb.',
b'citertools\ncycle\n(c__builtin__\niter\n(](K\x01K\x02K\x03etRK\x01btR(]K\x01aK\x00tb.',
b'\x80\x02citertools\ncycle\nc__builtin__\niter\n](K\x01K\x02K\x03e\x85RK\x01b\x85R]K\x01aK\x00\x86b.',
b'\x80\x03citertools\ncycle\ncbuiltins\niter\n](K\x01K\x02K\x03e\x85RK\x01b\x85R]K\x01aK\x00\x86b.',
b'\x80\x04\x95=\x00\x00\x00\x00\x00\x00\x00\x8c\titertools\x8c\x05cycle\x93\x8c\x08builtins\x8c\x04iter\x93](K\x01K\x02K\x03e\x85RK\x01b\x85R]K\x01aK\x00\x86b.',
b'citertools\ncycle\n(c__builtin__\niter\n((lp0\nI1\naI2\naI3\natRI1\nbtR(g0\nI1\ntb.',
b'citertools\ncycle\n(c__builtin__\niter\n(]q\x00(K\x01K\x02K\x03etRK\x01btR(h\x00K\x01tb.',
b'\x80\x02citertools\ncycle\nc__builtin__\niter\n]q\x00(K\x01K\x02K\x03e\x85RK\x01b\x85Rh\x00K\x01\x86b.',
b'\x80\x03citertools\ncycle\ncbuiltins\niter\n]q\x00(K\x01K\x02K\x03e\x85RK\x01b\x85Rh\x00K\x01\x86b.',
b'\x80\x04\x95<\x00\x00\x00\x00\x00\x00\x00\x8c\titertools\x8c\x05cycle\x93\x8c\x08builtins\x8c\x04iter\x93]\x94(K\x01K\x02K\x03e\x85RK\x01b\x85Rh\x00K\x01\x86b.',
b'citertools\ncycle\n(c__builtin__\niter\n((lI1\naI2\naI3\natRI1\nbtR((lI1\naI00\ntb.',
b'citertools\ncycle\n(c__builtin__\niter\n(](K\x01K\x02K\x03etRK\x01btR(]K\x01aI00\ntb.',
b'\x80\x02citertools\ncycle\nc__builtin__\niter\n](K\x01K\x02K\x03e\x85RK\x01b\x85R]K\x01a\x89\x86b.',
b'\x80\x03citertools\ncycle\ncbuiltins\niter\n](K\x01K\x02K\x03e\x85RK\x01b\x85R]K\x01a\x89\x86b.',
b'\x80\x04\x95<\x00\x00\x00\x00\x00\x00\x00\x8c\titertools\x8c\x05cycle\x93\x8c\x08builtins\x8c\x04iter\x93](K\x01K\x02K\x03e\x85RK\x01b\x85R]K\x01a\x89\x86b.',
b'citertools\ncycle\n(c__builtin__\niter\n((lp0\nI1\naI2\naI3\natRI1\nbtR(g0\nI01\ntb.',
b'citertools\ncycle\n(c__builtin__\niter\n(]q\x00(K\x01K\x02K\x03etRK\x01btR(h\x00I01\ntb.',
b'\x80\x02citertools\ncycle\nc__builtin__\niter\n]q\x00(K\x01K\x02K\x03e\x85RK\x01b\x85Rh\x00\x88\x86b.',
b'\x80\x03citertools\ncycle\ncbuiltins\niter\n]q\x00(K\x01K\x02K\x03e\x85RK\x01b\x85Rh\x00\x88\x86b.',
b'\x80\x04\x95;\x00\x00\x00\x00\x00\x00\x00\x8c\titertools\x8c\x05cycle\x93\x8c\x08builtins\x8c\x04iter\x93]\x94(K\x01K\x02K\x03e\x85RK\x01b\x85Rh\x00\x88\x86b.',
]
assert len(testcases) == 20
for t in testcases:
it = pickle.loads(t)
self.assertEqual(take(10, it), [2, 3, 1, 2, 3, 1, 2, 3, 1, 2])
@pickle_deprecated
def test_cycle_setstate(self):
# Verify both modes for restoring state
# Mode 0 is efficient. It uses an incompletely consumed input
# iterator to build a cycle object and then passes in state with
# a list of previously consumed values. There is no data
# overlap between the two.
c = cycle('defg')
c.__setstate__((list('abc'), 0))
self.assertEqual(take(20, c), list('defgabcdefgabcdefgab'))
# Mode 1 is inefficient. It starts with a cycle object built
# from an iterator over the remaining elements in a partial
# cycle and then passes in state with all of the previously
# seen values (this overlaps values included in the iterator).
c = cycle('defg')
c.__setstate__((list('abcdefg'), 1))
self.assertEqual(take(20, c), list('defgabcdefgabcdefgab'))
# The first argument to setstate needs to be a tuple
with self.assertRaises(TypeError):
cycle('defg').__setstate__([list('abcdefg'), 0])
# The first argument in the setstate tuple must be a list
with self.assertRaises(TypeError):
c = cycle('defg')
c.__setstate__((tuple('defg'), 0))
take(20, c)
# The second argument in the setstate tuple must be an int
with self.assertRaises(TypeError):
cycle('defg').__setstate__((list('abcdefg'), 'x'))
self.assertRaises(TypeError, cycle('').__setstate__, ())
self.assertRaises(TypeError, cycle('').__setstate__, ([],))
@pickle_deprecated
def test_groupby(self):
# Check whether it accepts arguments correctly
self.assertEqual([], list(groupby([])))
self.assertEqual([], list(groupby([], key=id)))
self.assertRaises(TypeError, list, groupby('abc', []))
self.assertRaises(TypeError, groupby, None)
self.assertRaises(TypeError, groupby, 'abc', lambda x:x, 10)
# Check normal input
s = [(0, 10, 20), (0, 11,21), (0,12,21), (1,13,21), (1,14,22),
(2,15,22), (3,16,23), (3,17,23)]
dup = []
for k, g in groupby(s, lambda r:r[0]):
for elem in g:
self.assertEqual(k, elem[0])
dup.append(elem)
self.assertEqual(s, dup)
# Check normal pickled
for proto in range(pickle.HIGHEST_PROTOCOL + 1):
dup = []
for k, g in pickle.loads(pickle.dumps(groupby(s, testR), proto)):
for elem in g:
self.assertEqual(k, elem[0])
dup.append(elem)
self.assertEqual(s, dup)
# Check nested case
dup = []
for k, g in groupby(s, testR):
for ik, ig in groupby(g, testR2):
for elem in ig:
self.assertEqual(k, elem[0])
self.assertEqual(ik, elem[2])
dup.append(elem)
self.assertEqual(s, dup)
# Check nested and pickled
for proto in range(pickle.HIGHEST_PROTOCOL + 1):
dup = []
for k, g in pickle.loads(pickle.dumps(groupby(s, testR), proto)):
for ik, ig in pickle.loads(pickle.dumps(groupby(g, testR2), proto)):
for elem in ig:
self.assertEqual(k, elem[0])
self.assertEqual(ik, elem[2])
dup.append(elem)
self.assertEqual(s, dup)
# Check case where inner iterator is not used
keys = [k for k, g in groupby(s, testR)]
expectedkeys = set([r[0] for r in s])
self.assertEqual(set(keys), expectedkeys)
self.assertEqual(len(keys), len(expectedkeys))
# Check case where inner iterator is used after advancing the groupby
# iterator
s = list(zip('AABBBAAAA', range(9)))
it = groupby(s, testR)
_, g1 = next(it)
_, g2 = next(it)
_, g3 = next(it)
self.assertEqual(list(g1), [])
self.assertEqual(list(g2), [])
self.assertEqual(next(g3), ('A', 5))
list(it) # exhaust the groupby iterator
self.assertEqual(list(g3), [])
for proto in range(pickle.HIGHEST_PROTOCOL + 1):
it = groupby(s, testR)
_, g = next(it)
next(it)
next(it)
self.assertEqual(list(pickle.loads(pickle.dumps(g, proto))), [])
# Exercise pipes and filters style
s = 'abracadabra'
# sort s | uniq
r = [k for k, g in groupby(sorted(s))]
self.assertEqual(r, ['a', 'b', 'c', 'd', 'r'])
# sort s | uniq -d
r = [k for k, g in groupby(sorted(s)) if list(islice(g,1,2))]
self.assertEqual(r, ['a', 'b', 'r'])
# sort s | uniq -c
r = [(len(list(g)), k) for k, g in groupby(sorted(s))]
self.assertEqual(r, [(5, 'a'), (2, 'b'), (1, 'c'), (1, 'd'), (2, 'r')])
# sort s | uniq -c | sort -rn | head -3
r = sorted([(len(list(g)) , k) for k, g in groupby(sorted(s))], reverse=True)[:3]
self.assertEqual(r, [(5, 'a'), (2, 'r'), (2, 'b')])
# iter.__next__ failure
class ExpectedError(Exception):
pass
def delayed_raise(n=0):
for i in range(n):
yield 'yo'
raise ExpectedError
def gulp(iterable, keyp=None, func=list):
return [func(g) for k, g in groupby(iterable, keyp)]
# iter.__next__ failure on outer object
self.assertRaises(ExpectedError, gulp, delayed_raise(0))
# iter.__next__ failure on inner object
self.assertRaises(ExpectedError, gulp, delayed_raise(1))
# __eq__ failure
class DummyCmp:
def __eq__(self, dst):
raise ExpectedError
s = [DummyCmp(), DummyCmp(), None]
# __eq__ failure on outer object
self.assertRaises(ExpectedError, gulp, s, func=id)
# __eq__ failure on inner object
self.assertRaises(ExpectedError, gulp, s)
# keyfunc failure
def keyfunc(obj):
if keyfunc.skip > 0:
keyfunc.skip -= 1
return obj
else:
raise ExpectedError
# keyfunc failure on outer object
keyfunc.skip = 0
self.assertRaises(ExpectedError, gulp, [None], keyfunc)
keyfunc.skip = 1
self.assertRaises(ExpectedError, gulp, [None, None], keyfunc)
def test_filter(self):
self.assertEqual(list(filter(isEven, range(6))), [0,2,4])
self.assertEqual(list(filter(None, [0,1,0,2,0])), [1,2])
self.assertEqual(list(filter(bool, [0,1,0,2,0])), [1,2])
self.assertEqual(take(4, filter(isEven, count())), [0,2,4,6])
self.assertRaises(TypeError, filter)
self.assertRaises(TypeError, filter, lambda x:x)
self.assertRaises(TypeError, filter, lambda x:x, range(6), 7)
self.assertRaises(TypeError, filter, isEven, 3)
self.assertRaises(TypeError, next, filter(range(6), range(6)))
# check copy, deepcopy, pickle
ans = [0,2,4]
c = filter(isEven, range(6))
self.assertEqual(list(copy.copy(c)), ans)
c = filter(isEven, range(6))
self.assertEqual(list(copy.deepcopy(c)), ans)
for proto in range(pickle.HIGHEST_PROTOCOL + 1):
c = filter(isEven, range(6))
self.assertEqual(list(pickle.loads(pickle.dumps(c, proto))), ans)
next(c)
self.assertEqual(list(pickle.loads(pickle.dumps(c, proto))), ans[1:])
for proto in range(pickle.HIGHEST_PROTOCOL + 1):
c = filter(isEven, range(6))
self.pickletest(proto, c)
@pickle_deprecated
def test_filterfalse(self):
self.assertEqual(list(filterfalse(isEven, range(6))), [1,3,5])
self.assertEqual(list(filterfalse(None, [0,1,0,2,0])), [0,0,0])
self.assertEqual(list(filterfalse(bool, [0,1,0,2,0])), [0,0,0])
self.assertEqual(take(4, filterfalse(isEven, count())), [1,3,5,7])
self.assertRaises(TypeError, filterfalse)
self.assertRaises(TypeError, filterfalse, lambda x:x)
self.assertRaises(TypeError, filterfalse, lambda x:x, range(6), 7)
self.assertRaises(TypeError, filterfalse, isEven, 3)
self.assertRaises(TypeError, next, filterfalse(range(6), range(6)))
for proto in range(pickle.HIGHEST_PROTOCOL + 1):
self.pickletest(proto, filterfalse(isEven, range(6)))
def test_zip(self):
# XXX This is rather silly now that builtin zip() calls zip()...
ans = [(x,y) for x, y in zip('abc',count())]
self.assertEqual(ans, [('a', 0), ('b', 1), ('c', 2)])
self.assertEqual(list(zip('abc', range(6))), lzip('abc', range(6)))
self.assertEqual(list(zip('abcdef', range(3))), lzip('abcdef', range(3)))
self.assertEqual(take(3,zip('abcdef', count())), lzip('abcdef', range(3)))
self.assertEqual(list(zip('abcdef')), lzip('abcdef'))
self.assertEqual(list(zip()), lzip())
self.assertRaises(TypeError, zip, 3)
self.assertRaises(TypeError, zip, range(3), 3)
self.assertEqual([tuple(list(pair)) for pair in zip('abc', 'def')],
lzip('abc', 'def'))
self.assertEqual([pair for pair in zip('abc', 'def')],
lzip('abc', 'def'))
@support.impl_detail("tuple reuse is specific to CPython")
@pickle_deprecated