| import unittest |
| from test import support |
| from itertools import * |
| from weakref import proxy |
| import sys |
| import operator |
| import random |
| from functools import reduce |
| 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 |
| |
| class StopNow: |
| 'Class emulating an empty iterable.' |
| def __iter__(self): |
| return self |
| def __next__(self): |
| raise StopIteration |
| |
| def take(n, seq): |
| 'Convenience function for partially consuming a long of infinite iterable' |
| return list(islice(seq, n)) |
| |
| def prod(iterable): |
| return reduce(operator.mul, iterable, 1) |
| |
| def fact(n): |
| 'Factorial' |
| return prod(range(1, n+1)) |
| |
| class TestBasicOps(unittest.TestCase): |
| def test_chain(self): |
| |
| def chain2(*iterables): |
| 'Pure python version in the docs' |
| for it in iterables: |
| for element in it: |
| yield element |
| |
| for c in (chain, chain2): |
| self.assertEqual(list(c('abc', 'def')), list('abcdef')) |
| self.assertEqual(list(c('abc')), list('abc')) |
| self.assertEqual(list(c('')), []) |
| self.assertEqual(take(4, c('abc', 'def')), list('abcd')) |
| self.assertRaises(TypeError, list,c(2, 3)) |
| |
| def test_chain_from_iterable(self): |
| self.assertEqual(list(chain.from_iterable(['abc', 'def'])), list('abcdef')) |
| self.assertEqual(list(chain.from_iterable(['abc'])), list('abc')) |
| self.assertEqual(list(chain.from_iterable([''])), []) |
| self.assertEqual(take(4, chain.from_iterable(['abc', 'def'])), list('abcd')) |
| self.assertRaises(TypeError, list, chain.from_iterable([2, 3])) |
| |
| def test_combinations(self): |
| self.assertRaises(TypeError, combinations, 'abc') # missing r argument |
| self.assertRaises(TypeError, combinations, 'abc', 2, 1) # too many arguments |
| self.assertRaises(TypeError, combinations, None) # pool is not iterable |
| self.assertRaises(ValueError, combinations, 'abc', -2) # r is negative |
| self.assertRaises(ValueError, combinations, 'abc', 32) # r is too big |
| self.assertEqual(list(combinations(range(4), 3)), |
| [(0,1,2), (0,1,3), (0,2,3), (1,2,3)]) |
| |
| def combinations1(iterable, r): |
| 'Pure python version shown in the docs' |
| pool = tuple(iterable) |
| n = len(pool) |
| 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) |
| |
| for n in range(7): |
| values = [5*x-12 for x in range(n)] |
| for r in range(n+1): |
| result = list(combinations(values, r)) |
| self.assertEqual(len(result), 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.assert_(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 first pure python version |
| |
| # Test implementation detail: tuple re-use |
| self.assertEqual(len(set(map(id, combinations('abcde', 3)))), 1) |
| self.assertNotEqual(len(set(map(id, list(combinations('abcde', 3))))), 1) |
| |
| def test_permutations(self): |
| self.assertRaises(TypeError, permutations) # too few arguments |
| self.assertRaises(TypeError, permutations, 'abc', 2, 1) # too many arguments |
| self.assertRaises(TypeError, permutations, None) # pool is not iterable |
| self.assertRaises(ValueError, permutations, 'abc', -2) # r is negative |
| self.assertRaises(ValueError, permutations, 'abc', 32) # r is too big |
| 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 |
| 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+1): |
| result = list(permutations(values, r)) |
| self.assertEqual(len(result), 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.assert_(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 first pure python version |
| if r == n: |
| self.assertEqual(result, list(permutations(values, None))) # test r as None |
| self.assertEqual(result, list(permutations(values))) # test default r |
| |
| # Test implementation detail: tuple re-use |
| self.assertEqual(len(set(map(id, permutations('abcde', 3)))), 1) |
| self.assertNotEqual(len(set(map(id, list(permutations('abcde', 3))))), 1) |
| |
| 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) |
| self.assertRaises(TypeError, count, 'a') |
| self.assertEqual(list(islice(count(maxsize-5), 10)), |
| list(range(maxsize-5, maxsize+5))) |
| self.assertEqual(list(islice(count(-maxsize-5), 10)), |
| list(range(-maxsize-5, -maxsize+5))) |
| 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) |
| for i in (-sys.maxsize-5, -sys.maxsize+5 ,-10, -1, 0, 10, sys.maxsize-5, sys.maxsize+5): |
| # Test repr (ignoring the L in longs) |
| r1 = repr(count(i)).replace('L', '') |
| r2 = 'count(%r)'.__mod__(i).replace('L', '') |
| self.assertEqual(r1, r2) |
| |
| def test_cycle(self): |
| self.assertEqual(take(10, cycle('abc')), list('abcabcabca')) |
| self.assertEqual(list(cycle('')), []) |
| self.assertRaises(TypeError, cycle) |
| self.assertRaises(TypeError, cycle, 5) |
| self.assertEqual(list(islice(cycle(gen3()),10)), [0,1,2,0,1,2,0,1,2,0]) |
| |
| def test_groupby(self): |
| # Check whether it accepts arguments correctly |
| self.assertEqual([], list(groupby([]))) |
| self.assertEqual([], list(groupby([], key=id))) |
| self.assertRaises(TypeError, list, groupby('abc', [])) |
| self.assertRaises(TypeError, groupby, None) |
| self.assertRaises(TypeError, groupby, 'abc', lambda x:x, 10) |
| |
| # Check normal input |
| s = [(0, 10, 20), (0, 11,21), (0,12,21), (1,13,21), (1,14,22), |
| (2,15,22), (3,16,23), (3,17,23)] |
| dup = [] |
| for k, g in groupby(s, lambda r:r[0]): |
| for elem in g: |
| self.assertEqual(k, elem[0]) |
| dup.append(elem) |
| self.assertEqual(s, dup) |
| |
| # Check nested case |
| dup = [] |
| for k, g in groupby(s, lambda r:r[0]): |
| for ik, ig in groupby(g, lambda r:r[2]): |
| for elem in ig: |
| self.assertEqual(k, elem[0]) |
| self.assertEqual(ik, elem[2]) |
| dup.append(elem) |
| self.assertEqual(s, dup) |
| |
| # Check case where inner iterator is not used |
| keys = [k for k, g in groupby(s, lambda r:r[0])] |
| expectedkeys = set([r[0] for r in s]) |
| self.assertEqual(set(keys), expectedkeys) |
| self.assertEqual(len(keys), len(expectedkeys)) |
| |
| # Exercise pipes and filters style |
| s = 'abracadabra' |
| # sort s | uniq |
| r = [k for k, g in groupby(sorted(s))] |
| self.assertEqual(r, ['a', 'b', 'c', 'd', 'r']) |
| # sort s | uniq -d |
| r = [k for k, g in groupby(sorted(s)) if list(islice(g,1,2))] |
| self.assertEqual(r, ['a', 'b', 'r']) |
| # sort s | uniq -c |
| r = [(len(list(g)), k) for k, g in groupby(sorted(s))] |
| self.assertEqual(r, [(5, 'a'), (2, 'b'), (1, 'c'), (1, 'd'), (2, 'r')]) |
| # sort s | uniq -c | sort -rn | head -3 |
| r = sorted([(len(list(g)) , k) for k, g in groupby(sorted(s))], reverse=True)[:3] |
| self.assertEqual(r, [(5, 'a'), (2, 'r'), (2, 'b')]) |
| |
| # iter.__next__ failure |
| class ExpectedError(Exception): |
| pass |
| def delayed_raise(n=0): |
| for i in range(n): |
| yield 'yo' |
| raise ExpectedError |
| def gulp(iterable, keyp=None, func=list): |
| return [func(g) for k, g in groupby(iterable, keyp)] |
| |
| # iter.__next__ failure on outer object |
| self.assertRaises(ExpectedError, gulp, delayed_raise(0)) |
| # iter.__next__ failure on inner object |
| self.assertRaises(ExpectedError, gulp, delayed_raise(1)) |
| |
| # __cmp__ failure |
| class DummyCmp: |
| def __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))) |
| |
| 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))) |
| |
| 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) |
| # Check tuple re-use (implementation detail) |
| 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')) |
| ids = list(map(id, zip('abc', 'def'))) |
| self.assertEqual(min(ids), max(ids)) |
| ids = list(map(id, list(zip('abc', 'def')))) |
| self.assertEqual(len(dict.fromkeys(ids)), len(ids)) |
| |
| def test_ziplongest(self): |
| for args in [ |
| ['abc', range(6)], |
| [range(6), 'abc'], |
| [range(1000), range(2000,2100), range(3000,3050)], |
| [range(1000), range(0), range(3000,3050), range(1200), range(1500)], |
| [range(1000), range(0), range(3000,3050), range(1200), range(1500), range(0)], |
| ]: |
| target = [tuple([arg[i] if i < len(arg) else None for arg in args]) |
| for i in range(max(map(len, args)))] |
| self.assertEqual(list(zip_longest(*args)), target) |
| self.assertEqual(list(zip_longest(*args, **{})), target) |
| target = [tuple((e is None and 'X' or e) for e in t) for t in target] # Replace None fills with 'X' |
| self.assertEqual(list(zip_longest(*args, **dict(fillvalue='X'))), target) |
| |
| self.assertEqual(take(3,zip_longest('abcdef', count())), list(zip('abcdef', range(3)))) # take 3 from infinite input |
| |
| self.assertEqual(list(zip_longest()), list(zip())) |
| self.assertEqual(list(zip_longest([])), list(zip([]))) |
| self.assertEqual(list(zip_longest('abcdef')), list(zip('abcdef'))) |
| |
| self.assertEqual(list(zip_longest('abc', 'defg', **{})), |
| list(zip(list('abc')+[None], 'defg'))) # empty keyword dict |
| self.assertRaises(TypeError, zip_longest, 3) |
| self.assertRaises(TypeError, zip_longest, range(3), 3) |
| |
| for stmt in [ |
| "zip_longest('abc', fv=1)", |
| "zip_longest('abc', fillvalue=1, bogus_keyword=None)", |
| ]: |
| try: |
| eval(stmt, globals(), locals()) |
| except TypeError: |
| pass |
| else: |
| self.fail('Did not raise Type in: ' + stmt) |
| |
| # Check tuple re-use (implementation detail) |
| self.assertEqual([tuple(list(pair)) for pair in zip_longest('abc', 'def')], |
| list(zip('abc', 'def'))) |
| self.assertEqual([pair for pair in zip_longest('abc', 'def')], |
| list(zip('abc', 'def'))) |
| ids = list(map(id, zip_longest('abc', 'def'))) |
| self.assertEqual(min(ids), max(ids)) |
| ids = list(map(id, list(zip_longest('abc', 'def')))) |
| self.assertEqual(len(dict.fromkeys(ids)), len(ids)) |
| |
| def test_product(self): |
| for args, result in [ |
| ([], [()]), # zero iterables |
| (['ab'], [('a',), ('b',)]), # one iterable |
| ([range(2), range(3)], [(0,0), (0,1), (0,2), (1,0), (1,1), (1,2)]), # two iterables |
| ([range(0), range(2), range(3)], []), # first iterable with zero length |
| ([range(2), range(0), range(3)], []), # middle iterable with zero length |
| ([range(2), range(3), range(0)], []), # last iterable with zero length |
| ]: |
| self.assertEqual(list(product(*args)), result) |
| for r in range(4): |
| self.assertEqual(list(product(*(args*r))), |
| list(product(*args, **dict(repeat=r)))) |
| self.assertEqual(len(list(product(*[range(7)]*6))), 7**6) |
| self.assertRaises(TypeError, product, range(6), None) |
| |
| def product1(*args, **kwds): |
| pools = list(map(tuple, args)) * kwds.get('repeat', 1) |
| n = len(pools) |
| if n == 0: |
| yield () |
| return |
| if any(len(pool) == 0 for pool in pools): |
| return |
| indices = [0] * n |
| yield tuple(pool[i] for pool, i in zip(pools, indices)) |
| while 1: |
| for i in reversed(range(n)): # right to left |
| if indices[i] == len(pools[i]) - 1: |
| continue |
| indices[i] += 1 |
| for j in range(i+1, n): |
| indices[j] = 0 |
| yield tuple(pool[i] for pool, i in zip(pools, indices)) |
| break |
| else: |
| return |
| |
| def product2(*args, **kwds): |
| 'Pure python version used in docs' |
| pools = list(map(tuple, args)) * kwds.get('repeat', 1) |
| result = [[]] |
| for pool in pools: |
| result = [x+[y] for x in result for y in pool] |
| for prod in result: |
| yield tuple(prod) |
| |
| argtypes = ['', 'abc', '', range(0), range(4), dict(a=1, b=2, c=3), |
| set('abcdefg'), range(11), tuple(range(13))] |
| for i in range(100): |
| args = [random.choice(argtypes) for j in range(random.randrange(5))] |
| expected_len = prod(map(len, args)) |
| self.assertEqual(len(list(product(*args))), expected_len) |
| self.assertEqual(list(product(*args)), list(product1(*args))) |
| self.assertEqual(list(product(*args)), list(product2(*args))) |
| args = map(iter, args) |
| self.assertEqual(len(list(product(*args))), expected_len) |
| |
| # Test 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(lzip(range(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_map(self): |
| self.assertEqual(list(map(operator.pow, range(3), range(1,7))), |
| [0**1, 1**2, 2**3]) |
| def tupleize(*args): |
| return args |
| self.assertEqual(list(map(tupleize, 'abc', range(5))), |
| [('a',0),('b',1),('c',2)]) |
| self.assertEqual(list(map(tupleize, 'abc', count())), |
| [('a',0),('b',1),('c',2)]) |
| self.assertEqual(take(2,map(tupleize, 'abc', count())), |
| [('a',0),('b',1)]) |
| self.assertEqual(list(map(operator.pow, [])), []) |
| self.assertRaises(TypeError, map) |
| self.assertRaises(TypeError, list, map(None, range(3), range(3))) |
| self.assertRaises(TypeError, map, operator.neg) |
| self.assertRaises(TypeError, next, map(10, range(5))) |
| self.assertRaises(ValueError, next, map(errfunc, [4], [5])) |
| self.assertRaises(TypeError, next, map(onearg, [4], [5])) |
| |
| 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, zip(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, next, starmap(10, [(4,5)])) |
| self.assertRaises(ValueError, next, starmap(errfunc, [(4,5)])) |
| self.assertRaises(TypeError, next, starmap(onearg, [(4,5)])) |
| |
| 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(range(100), *args)), |
| list(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(range(100), *args)), |
| list(range(*tgtargs))) |
| |
| # Test stop=None |
| self.assertEqual(list(islice(range(10), None)), list(range(10))) |
| self.assertEqual(list(islice(range(10), None, None)), list(range(10))) |
| self.assertEqual(list(islice(range(10), None, None, None)), list(range(10))) |
| self.assertEqual(list(islice(range(10), 2, None)), list(range(2, 10))) |
| self.assertEqual(list(islice(range(10), 1, None, 2)), list(range(1, 10, 2))) |
| |
| # Test number of items consumed SF #1171417 |
| it = iter(range(10)) |
| self.assertEqual(list(islice(it, 3)), list(range(3))) |
| self.assertEqual(list(it), list(range(3, 10))) |
| |
| # Test invalid arguments |
| self.assertRaises(TypeError, islice, range(10)) |
| self.assertRaises(TypeError, islice, range(10), 1, 2, 3, 4) |
| self.assertRaises(ValueError, islice, range(10), -5, 10, 1) |
| self.assertRaises(ValueError, islice, range(10), 1, -5, -1) |
| self.assertRaises(ValueError, islice, range(10), 1, 10, -1) |
| self.assertRaises(ValueError, islice, range(10), 1, 10, 0) |
| self.assertRaises(ValueError, islice, range(10), 'a') |
| self.assertRaises(ValueError, islice, range(10), 'a', 1) |
| self.assertRaises(ValueError, islice, range(10), 1, 'a') |
| self.assertRaises(ValueError, islice, range(10), 'a', 1, 1) |
| self.assertRaises(ValueError, islice, range(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, next, takewhile(10, [(4,5)])) |
| self.assertRaises(ValueError, next, takewhile(errfunc, [(4,5)])) |
| t = takewhile(bool, [1, 1, 1, 0, 0, 0]) |
| self.assertEqual(list(t), [1, 1, 1]) |
| self.assertRaises(StopIteration, next, t) |
| |
| 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, next, dropwhile(10, [(4,5)])) |
| self.assertRaises(ValueError, next, dropwhile(errfunc, [(4,5)])) |
| |
| def test_tee(self): |
| n = 200 |
| def irange(n): |
| for i in range(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(lzip(a,b), lzip(range(n), range(n))) |
| |
| a, b = tee(irange(n)) # test 0% interleaved |
| self.assertEqual(list(a), list(range(n))) |
| self.assertEqual(list(b), list(range(n))) |
| |
| a, b = tee(irange(n)) # test dealloc of leading iterator |
| for i in range(100): |
| self.assertEqual(next(a), i) |
| del a |
| self.assertEqual(list(b), list(range(n))) |
| |
| a, b = tee(irange(n)) # test dealloc of trailing iterator |
| for i in range(100): |
| self.assertEqual(next(a), i) |
| del b |
| self.assertEqual(list(a), list(range(100, n))) |
| |
| for j in range(5): # test randomly interleaved |
| order = [0]*n + [1]*n |
| random.shuffle(order) |
| lists = ([], []) |
| its = tee(irange(n)) |
| for i in order: |
| value = next(its[i]) |
| lists[i].append(value) |
| self.assertEqual(lists[0], list(range(n))) |
| self.assertEqual(lists[1], list(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(range(2000), 3) |
| for i in range(100): |
| self.assertEqual(next(a), i) |
| self.assertEqual(list(b), list(range(2000))) |
| self.assertEqual([next(c), next(c)], list(range(2))) |
| self.assertEqual(list(a), list(range(100,2000))) |
| self.assertEqual(list(c), list(range(2,2000))) |
| |
| # test values of n |
| self.assertRaises(TypeError, tee, 'abc', 'invalid') |
| self.assertRaises(ValueError, tee, [], -1) |
| for n in range(5): |
| result = tee('abc', n) |
| self.assertEqual(type(result), tuple) |
| self.assertEqual(len(result), n) |
| self.assertEqual([list(x) for x in 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(range(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, next, zip()) |
| |
| for f in (chain, cycle, zip, groupby): |
| self.assertRaises(StopIteration, next, f([])) |
| self.assertRaises(StopIteration, next, f(StopNow())) |
| |
| self.assertRaises(StopIteration, next, islice([], None)) |
| self.assertRaises(StopIteration, next, islice(StopNow(), None)) |
| |
| p, q = tee([]) |
| self.assertRaises(StopIteration, next, p) |
| self.assertRaises(StopIteration, next, q) |
| p, q = tee(StopNow()) |
| self.assertRaises(StopIteration, next, p) |
| self.assertRaises(StopIteration, next, q) |
| |
| self.assertRaises(StopIteration, next, repeat(None, 0)) |
| |
| for f in (filter, filterfalse, map, takewhile, dropwhile, starmap): |
| self.assertRaises(StopIteration, next, f(lambda x:x, [])) |
| self.assertRaises(StopIteration, next, f(lambda x:x, StopNow())) |
| |
| class TestExamples(unittest.TestCase): |
| |
| def test_chain(self): |
| self.assertEqual(''.join(chain('ABC', 'DEF')), 'ABCDEF') |
| |
| def test_chain_from_iterable(self): |
| self.assertEqual(''.join(chain.from_iterable(['ABC', 'DEF'])), 'ABCDEF') |
| |
| def test_combinations(self): |
| self.assertEqual(list(combinations('ABCD', 2)), |
| [('A','B'), ('A','C'), ('A','D'), ('B','C'), ('B','D'), ('C','D')]) |
| self.assertEqual(list(combinations(range(4), 3)), |
| [(0,1,2), (0,1,3), (0,2,3), (1,2,3)]) |
| |
| def test_count(self): |
| self.assertEqual(list(islice(count(10), 5)), [10, 11, 12, 13, 14]) |
| |
| def test_cycle(self): |
| self.assertEqual(list(islice(cycle('ABCD'), 12)), list('ABCDABCDABCD')) |
| |
| def test_dropwhile(self): |
| self.assertEqual(list(dropwhile(lambda x: x<5, [1,4,6,4,1])), [6,4,1]) |
| |
| def test_groupby(self): |
| self.assertEqual([k for k, g in groupby('AAAABBBCCDAABBB')], |
| list('ABCDAB')) |
| self.assertEqual([(list(g)) for k, g in groupby('AAAABBBCCD')], |
| [list('AAAA'), list('BBB'), list('CC'), list('D')]) |
| |
| def test_filter(self): |
| self.assertEqual(list(filter(lambda x: x%2, range(10))), [1,3,5,7,9]) |
| |
| def test_filterfalse(self): |
| self.assertEqual(list(filterfalse(lambda x: x%2, range(10))), [0,2,4,6,8]) |
| |
| def test_map(self): |
| self.assertEqual(list(map(pow, (2,3,10), (5,2,3))), [32, 9, 1000]) |
| |
| def test_islice(self): |
| self.assertEqual(list(islice('ABCDEFG', 2)), list('AB')) |
| self.assertEqual(list(islice('ABCDEFG', 2, 4)), list('CD')) |
| self.assertEqual(list(islice('ABCDEFG', 2, None)), list('CDEFG')) |
| self.assertEqual(list(islice('ABCDEFG', 0, None, 2)), list('ACEG')) |
| |
| def test_zip(self): |
| self.assertEqual(list(zip('ABCD', 'xy')), [('A', 'x'), ('B', 'y')]) |
| |
| def test_zip_longest(self): |
| self.assertEqual(list(zip_longest('ABCD', 'xy', fillvalue='-')), |
| [('A', 'x'), ('B', 'y'), ('C', '-'), ('D', '-')]) |
| |
| def test_permutations(self): |
| self.assertEqual(list(permutations('ABCD', 2)), |
| list(map(tuple, 'AB AC AD BA BC BD CA CB CD DA DB DC'.split()))) |
| self.assertEqual(list(permutations(range(3))), |
| [(0,1,2), (0,2,1), (1,0,2), (1,2,0), (2,0,1), (2,1,0)]) |
| |
| def test_product(self): |
| self.assertEqual(list(product('ABCD', 'xy')), |
| list(map(tuple, 'Ax Ay Bx By Cx Cy Dx Dy'.split()))) |
| self.assertEqual(list(product(range(2), repeat=3)), |
| [(0,0,0), (0,0,1), (0,1,0), (0,1,1), |
| (1,0,0), (1,0,1), (1,1,0), (1,1,1)]) |
| |
| def test_repeat(self): |
| self.assertEqual(list(repeat(10, 3)), [10, 10, 10]) |
| |
| def test_stapmap(self): |
| self.assertEqual(list(starmap(pow, [(2,5), (3,2), (10,3)])), |
| [32, 9, 1000]) |
| |
| def test_takewhile(self): |
| self.assertEqual(list(takewhile(lambda x: x<5, [1,4,6,4,1])), [1,4]) |
| |
| |
| class TestGC(unittest.TestCase): |
| |
| def makecycle(self, iterator, container): |
| container.append(iterator) |
| next(iterator) |
| del container, iterator |
| |
| def test_chain(self): |
| a = [] |
| self.makecycle(chain(a), a) |
| |
| def test_chain_from_iterable(self): |
| a = [] |
| self.makecycle(chain.from_iterable([a]), a) |
| |
| def test_combinations(self): |
| a = [] |
| self.makecycle(combinations([1,2,a,3], 3), a) |
| |
| def test_cycle(self): |
| a = [] |
| self.makecycle(cycle([a]*2), a) |
| |
| def test_dropwhile(self): |
| a = [] |
| self.makecycle(dropwhile(bool, [0, a, a]), a) |
| |
| def test_groupby(self): |
| a = [] |
| self.makecycle(groupby([a]*2, lambda x:x), a) |
| |
| def test_issue2246(self): |
| # Issue 2246 -- the _grouper iterator was not included in GC |
| n = 10 |
| keyfunc = lambda x: x |
| for i, j in groupby(range(n), key=keyfunc): |
| keyfunc.__dict__.setdefault('x',[]).append(j) |
| |
| def test_filter(self): |
| a = [] |
| self.makecycle(filter(lambda x:True, [a]*2), a) |
| |
| def test_filterfalse(self): |
| a = [] |
| self.makecycle(filterfalse(lambda x:False, a), a) |
| |
| def test_zip(self): |
| a = [] |
| self.makecycle(zip([a]*2, [a]*3), a) |
| |
| def test_zip_longest(self): |
| a = [] |
| self.makecycle(zip_longest([a]*2, [a]*3), a) |
| b = [a, None] |
| self.makecycle(zip_longest([a]*2, [a]*3, fillvalue=b), a) |
| |
| def test_map(self): |
| a = [] |
| self.makecycle(map(lambda x:x, [a]*2), a) |
| |
| def test_islice(self): |
| a = [] |
| self.makecycle(islice([a]*2, None), a) |
| |
| def test_permutations(self): |
| a = [] |
| self.makecycle(permutations([1,2,a,3], 3), a) |
| |
| def test_product(self): |
| a = [] |
| self.makecycle(product([1,2,a,3], repeat=3), a) |
| |
| def test_repeat(self): |
| a = [] |
| self.makecycle(repeat(a), a) |
| |
| def test_starmap(self): |
| a = [] |
| self.makecycle(starmap(lambda *t: t, [(a,a)]*2), a) |
| |
| def test_takewhile(self): |
| a = [] |
| self.makecycle(takewhile(bool, [1, 0, a, a]), a) |
| |
| def R(seqn): |
| 'Regular generator' |
| for i in seqn: |
| yield i |
| |
| class G: |
| 'Sequence using __getitem__' |
| def __init__(self, seqn): |
| self.seqn = seqn |
| def __getitem__(self, i): |
| return self.seqn[i] |
| |
| class I: |
| 'Sequence using iterator protocol' |
| def __init__(self, seqn): |
| self.seqn = seqn |
| self.i = 0 |
| def __iter__(self): |
| return self |
| def __next__(self): |
| if self.i >= len(self.seqn): raise StopIteration |
| v = self.seqn[self.i] |
| self.i += 1 |
| return v |
| |
| class Ig: |
| 'Sequence using iterator protocol defined with a generator' |
| def __init__(self, seqn): |
| self.seqn = seqn |
| self.i = 0 |
| def __iter__(self): |
| for val in self.seqn: |
| yield val |
| |
| class X: |
| 'Missing __getitem__ and __iter__' |
| def __init__(self, seqn): |
| self.seqn = seqn |
| self.i = 0 |
| def __next__(self): |
| if self.i >= len(self.seqn): raise StopIteration |
| v = self.seqn[self.i] |
| self.i += 1 |
| return v |
| |
| class N: |
| 'Iterator missing __next__()' |
| def __init__(self, seqn): |
| self.seqn = seqn |
| self.i = 0 |
| def __iter__(self): |
| return self |
| |
| class E: |
| 'Test propagation of exceptions' |
| def __init__(self, seqn): |
| self.seqn = seqn |
| self.i = 0 |
| def __iter__(self): |
| return self |
| def __next__(self): |
| 3 // 0 |
| |
| class S: |
| 'Test immediate stop' |
| def __init__(self, seqn): |
| pass |
| def __iter__(self): |
| return self |
| def __next__(self): |
| raise StopIteration |
| |
| def L(seqn): |
| 'Test multiple tiers of iterators' |
| return chain(map(lambda x:x, R(Ig(G(seqn))))) |
| |
| |
| class TestVariousIteratorArgs(unittest.TestCase): |
| |
| def test_chain(self): |
| for s in ("123", "", range(1000), ('do', 1.2), range(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), range(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), range(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, 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), range(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, groupby, N(s)) |
| self.assertRaises(ZeroDivisionError, list, groupby(E(s))) |
| |
| def test_filter(self): |
| for s in (range(10), range(0), range(1000), (7,11), range(2000,2200,5)): |
| for g in (G, I, Ig, S, L, R): |
| self.assertEqual(list(filter(isEven, g(s))), |
| [x for x in g(s) if isEven(x)]) |
| self.assertRaises(TypeError, filter, isEven, X(s)) |
| self.assertRaises(TypeError, filter, isEven, N(s)) |
| self.assertRaises(ZeroDivisionError, list, filter(isEven, E(s))) |
| |
| def test_filterfalse(self): |
| for s in (range(10), range(0), range(1000), (7,11), range(2000,2200,5)): |
| for g in (G, I, Ig, S, L, R): |
| self.assertEqual(list(filterfalse(isEven, g(s))), |
| [x for x in g(s) if isOdd(x)]) |
| self.assertRaises(TypeError, filterfalse, isEven, X(s)) |
| self.assertRaises(TypeError, filterfalse, isEven, N(s)) |
| self.assertRaises(ZeroDivisionError, list, filterfalse(isEven, E(s))) |
| |
| def test_zip(self): |
| for s in ("123", "", range(1000), ('do', 1.2), range(2000,2200,5)): |
| for g in (G, I, Ig, S, L, R): |
| self.assertEqual(list(zip(g(s))), lzip(g(s))) |
| self.assertEqual(list(zip(g(s), g(s))), lzip(g(s), g(s))) |
| self.assertRaises(TypeError, zip, X(s)) |
| self.assertRaises(TypeError, zip, N(s)) |
| self.assertRaises(ZeroDivisionError, list, zip(E(s))) |
| |
| def test_ziplongest(self): |
| for s in ("123", "", range(1000), ('do', 1.2), range(2000,2200,5)): |
| for g in (G, I, Ig, S, L, R): |
| self.assertEqual(list(zip_longest(g(s))), list(zip(g(s)))) |
| self.assertEqual(list(zip_longest(g(s), g(s))), list(zip(g(s), g(s)))) |
| self.assertRaises(TypeError, zip_longest, X(s)) |
| self.assertRaises(TypeError, zip_longest, N(s)) |
| self.assertRaises(ZeroDivisionError, list, zip_longest(E(s))) |
| |
| def test_map(self): |
| for s in (range(10), range(0), range(100), (7,11), range(20,50,5)): |
| for g in (G, I, Ig, S, L, R): |
| self.assertEqual(list(map(onearg, g(s))), |
| [onearg(x) for x in g(s)]) |
| self.assertEqual(list(map(operator.pow, g(s), g(s))), |
| [x**x for x in g(s)]) |
| self.assertRaises(TypeError, map, onearg, X(s)) |
| self.assertRaises(TypeError, map, onearg, N(s)) |
| self.assertRaises(ZeroDivisionError, list, map(onearg, E(s))) |
| |
| def test_islice(self): |
| for s in ("12345", "", range(1000), ('do', 1.2), range(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, 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), range(20,50,5)): |
| for g in (G, I, Ig, S, L, R): |
| ss = lzip(s, s) |
| self.assertEqual(list(starmap(operator.pow, g(ss))), |
| [x**x for x in g(s)]) |
| self.assertRaises(TypeError, starmap, operator.pow, X(ss)) |
| self.assertRaises(TypeError, 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), range(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, 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), range(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, 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), range(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, tee, N(s)) |
| 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(next(z)) |
| return value |
| items = list(tuple2) |
| items[1:1] = list(tuple1) |
| gen = map(g, items) |
| z = zip(*[gen]*len(tuple1)) |
| next(z) |
| |
| 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, zip, filter, filterfalse, chain, map, |
| starmap, islice, takewhile, dropwhile, cycle): |
| class Subclass(cls): |
| def __init__(self, newarg=None, *args): |
| cls.__init__(self, *args) |
| try: |
| Subclass(newarg=1) |
| except TypeError as 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 zip(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 map(operator.pow, range(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.items()), key=itemgetter(1)) |
| >>> for k, g in groupby(di, itemgetter(1)): |
| ... print(k, list(map(itemgetter(0), g))) |
| ... |
| 1 ['a', 'c', 'e'] |
| 2 ['b', 'd', 'f'] |
| 3 ['g'] |
| |
| # Find runs of consecutive numbers using groupby. The key to the solution |
| # is differencing with a range so that consecutive numbers all appear in |
| # same group. |
| >>> data = [ 1, 4,5,6, 10, 15,16,17,18, 22, 25,26,27,28] |
| >>> for k, g in groupby(enumerate(data), lambda t:t[0]-t[1]): |
| ... print(list(map(operator.itemgetter(1), g))) |
| ... |
| [1] |
| [4, 5, 6] |
| [10] |
| [15, 16, 17, 18] |
| [22] |
| [25, 26, 27, 28] |
| |
| >>> def take(n, iterable): |
| ... "Return first n items of the iterable as a list" |
| ... return list(islice(iterable, n)) |
| |
| >>> def enumerate(iterable, start=0): |
| ... return zip(count(start), iterable) |
| |
| >>> def tabulate(function, start=0): |
| ... "Return function(0), function(1), ..." |
| ... return map(function, count(start)) |
| |
| >>> def nth(iterable, n): |
| ... "Returns the nth item or empty list" |
| ... return list(islice(iterable, n, n+1)) |
| |
| >>> def quantify(iterable, pred=bool): |
| ... "Count how many times the predicate is true" |
| ... return sum(map(pred, iterable)) |
| |
| >>> def padnone(iterable): |
| ... "Returns the sequence elements and then returns None indefinitely" |
| ... return chain(iterable, repeat(None)) |
| |
| >>> def ncycles(iterable, n): |
| ... "Returns the seqeuence elements n times" |
| ... return chain(*repeat(iterable, n)) |
| |
| >>> def dotproduct(vec1, vec2): |
| ... return sum(map(operator.mul, vec1, vec2)) |
| |
| >>> def flatten(listOfLists): |
| ... return list(chain.from_iterable(listOfLists)) |
| |
| >>> def repeatfunc(func, times=None, *args): |
| ... "Repeat calls to func with specified arguments." |
| ... " Example: repeatfunc(random.random)" |
| ... if times is None: |
| ... return starmap(func, repeat(args)) |
| ... else: |
| ... return starmap(func, repeat(args, times)) |
| |
| >>> def pairwise(iterable): |
| ... "s -> (s0,s1), (s1,s2), (s2, s3), ..." |
| ... a, b = tee(iterable) |
| ... try: |
| ... next(b) |
| ... except StopIteration: |
| ... pass |
| ... return zip(a, b) |
| |
| >>> def grouper(n, iterable, fillvalue=None): |
| ... "grouper(3, 'ABCDEFG', 'x') --> ABC DEF Gxx" |
| ... args = [iter(iterable)] * n |
| ... return zip_longest(fillvalue=fillvalue, *args) |
| |
| >>> def roundrobin(*iterables): |
| ... "roundrobin('ABC', 'D', 'EF') --> A D E B F C" |
| ... # Recipe credited to George Sakkis |
| ... pending = len(iterables) |
| ... nexts = cycle(iter(it).__next__ for it in iterables) |
| ... while pending: |
| ... try: |
| ... for next in nexts: |
| ... yield next() |
| ... except StopIteration: |
| ... pending -= 1 |
| ... nexts = cycle(islice(nexts, pending)) |
| |
| >>> def powerset(iterable): |
| ... "powerset('ab') --> set([]), set(['a']), set(['b']), set(['a', 'b'])" |
| ... # Recipe credited to Eric Raymond |
| ... pairs = [(2**i, x) for i, x in enumerate(iterable)] |
| ... for n in range(2**len(pairs)): |
| ... yield set(x for m, x in pairs if m&n) |
| |
| >>> def compress(data, selectors): |
| ... "compress('ABCDEF', [1,0,1,0,1,1]) --> A C E F" |
| ... return (d for d, s in zip(data, selectors) if s) |
| |
| >>> def combinations_with_replacement(iterable, r): |
| ... "combinations_with_replacement('ABC', 3) --> AA AB AC BB BC CC" |
| ... pool = tuple(iterable) |
| ... n = len(pool) |
| ... 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 unique_everseen(iterable, key=None): |
| ... "List unique elements, preserving order. Remember all elements ever seen." |
| ... # unique_everseen('AAAABBBCCDAABBB') --> A B C D |
| ... # unique_everseen('ABBCcAD', str.lower) --> A B C D |
| ... seen = set() |
| ... seen_add = seen.add |
| ... if key is None: |
| ... for element in iterable: |
| ... if element not in seen: |
| ... seen_add(element) |
| ... yield element |
| ... else: |
| ... for element in iterable: |
| ... k = key(element) |
| ... if k not in seen: |
| ... seen_add(k) |
| ... yield element |
| |
| >>> def unique_justseen(iterable, key=None): |
| ... "List unique elements, preserving order. Remember only the element just seen." |
| ... # unique_justseen('AAAABBBCCDAABBB') --> A B C D A B |
| ... # unique_justseen('ABBCcAD', str.lower) --> A B C A D |
| ... return map(next, map(itemgetter(1), groupby(iterable, key))) |
| |
| This is not part of the examples but it tests to make sure the definitions |
| perform as purported. |
| |
| >>> take(10, count()) |
| [0, 1, 2, 3, 4, 5, 6, 7, 8, 9] |
| |
| >>> list(enumerate('abc')) |
| [(0, 'a'), (1, 'b'), (2, 'c')] |
| |
| >>> list(islice(tabulate(lambda x: 2*x), 4)) |
| [0, 2, 4, 6] |
| |
| >>> nth('abcde', 3) |
| ['d'] |
| |
| >>> quantify(range(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, map(int, repeatfunc(random.random))) |
| [0, 0, 0, 0, 0] |
| |
| >>> list(pairwise('abcd')) |
| [('a', 'b'), ('b', 'c'), ('c', 'd')] |
| |
| >>> list(pairwise([])) |
| [] |
| |
| >>> list(pairwise('a')) |
| [] |
| |
| >>> list(islice(padnone('abc'), 0, 6)) |
| ['a', 'b', 'c', None, None, None] |
| |
| >>> list(ncycles('abc', 3)) |
| ['a', 'b', 'c', 'a', 'b', 'c', 'a', 'b', 'c'] |
| |
| >>> dotproduct([1,2,3], [4,5,6]) |
| 32 |
| |
| >>> list(grouper(3, 'abcdefg', 'x')) |
| [('a', 'b', 'c'), ('d', 'e', 'f'), ('g', 'x', 'x')] |
| |
| >>> list(roundrobin('abc', 'd', 'ef')) |
| ['a', 'd', 'e', 'b', 'f', 'c'] |
| |
| >>> list(map(sorted, powerset('ab'))) |
| [[], ['a'], ['b'], ['a', 'b']] |
| |
| >>> list(compress('abcdef', [1,0,1,0,1,1])) |
| ['a', 'c', 'e', 'f'] |
| |
| >>> list(combinations_with_replacement('abc', 2)) |
| [('a', 'a'), ('a', 'b'), ('a', 'c'), ('b', 'b'), ('b', 'c'), ('c', 'c')] |
| |
| >>> list(unique_everseen('AAAABBBCCDAABBB')) |
| ['A', 'B', 'C', 'D'] |
| |
| >>> list(unique_everseen('ABBCcAD', str.lower)) |
| ['A', 'B', 'C', 'D'] |
| |
| >>> list(unique_justseen('AAAABBBCCDAABBB')) |
| ['A', 'B', 'C', 'D', 'A', 'B'] |
| |
| >>> list(unique_justseen('ABBCcAD', str.lower)) |
| ['A', 'B', 'C', 'A', 'D'] |
| |
| """ |
| |
| __test__ = {'libreftest' : libreftest} |
| |
| def test_main(verbose=None): |
| test_classes = (TestBasicOps, TestVariousIteratorArgs, TestGC, |
| RegressionTests, LengthTransparency, |
| SubclassWithKwargsTest, TestExamples) |
| support.run_unittest(*test_classes) |
| |
| # verify reference counting |
| if verbose and hasattr(sys, "gettotalrefcount"): |
| import gc |
| counts = [None] * 5 |
| for i in range(len(counts)): |
| support.run_unittest(*test_classes) |
| gc.collect() |
| counts[i] = sys.gettotalrefcount() |
| print(counts) |
| |
| # doctest the examples in the library reference |
| support.run_doctest(sys.modules[__name__], verbose) |
| |
| if __name__ == "__main__": |
| test_main(verbose=True) |