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from collections import deque import unittest from test import test_support, seq_tests import gc import weakref import copy import cPickle as pickle import random import struct BIG = 100000 def fail(): raise SyntaxError yield 1 class BadCmp: def __eq__(self, other): raise RuntimeError class MutateCmp: def __init__(self, deque, result): self.deque = deque self.result = result def __eq__(self, other): self.deque.clear() return self.result class TestBasic(unittest.TestCase): def test_basics(self): d = deque(xrange(-5125, -5000)) d.__init__(xrange(200)) for i in xrange(200, 400): d.append(i) for i in reversed(xrange(-200, 0)): d.appendleft(i) self.assertEqual(list(d), range(-200, 400)) self.assertEqual(len(d), 600) left = [d.popleft() for i in xrange(250)] self.assertEqual(left, range(-200, 50)) self.assertEqual(list(d), range(50, 400)) right = [d.pop() for i in xrange(250)] right.reverse() self.assertEqual(right, range(150, 400)) self.assertEqual(list(d), range(50, 150)) def test_maxlen(self): self.assertRaises(ValueError, deque, 'abc', -1) self.assertRaises(ValueError, deque, 'abc', -2) it = iter(range(10)) d = deque(it, maxlen=3) self.assertEqual(list(it), []) self.assertEqual(repr(d), 'deque([7, 8, 9], maxlen=3)') self.assertEqual(list(d), range(7, 10)) self.assertEqual(d, deque(range(10), 3)) d.append(10) self.assertEqual(list(d), range(8, 11)) d.appendleft(7) self.assertEqual(list(d), range(7, 10)) d.extend([10, 11]) self.assertEqual(list(d), range(9, 12)) d.extendleft([8, 7]) self.assertEqual(list(d), range(7, 10)) d = deque(xrange(200), maxlen=10) d.append(d) test_support.unlink(test_support.TESTFN) fo = open(test_support.TESTFN, "wb") try: print >> fo, d, fo.close() fo = open(test_support.TESTFN, "rb") self.assertEqual(fo.read(), repr(d)) finally: fo.close() test_support.unlink(test_support.TESTFN) d = deque(range(10), maxlen=None) self.assertEqual(repr(d), 'deque([0, 1, 2, 3, 4, 5, 6, 7, 8, 9])') fo = open(test_support.TESTFN, "wb") try: print >> fo, d, fo.close() fo = open(test_support.TESTFN, "rb") self.assertEqual(fo.read(), repr(d)) finally: fo.close() test_support.unlink(test_support.TESTFN) def test_maxlen_zero(self): it = iter(range(100)) deque(it, maxlen=0) self.assertEqual(list(it), []) it = iter(range(100)) d = deque(maxlen=0) d.extend(it) self.assertEqual(list(it), []) it = iter(range(100)) d = deque(maxlen=0) d.extendleft(it) self.assertEqual(list(it), []) def test_maxlen_attribute(self): self.assertEqual(deque().maxlen, None) self.assertEqual(deque('abc').maxlen, None) self.assertEqual(deque('abc', maxlen=4).maxlen, 4) self.assertEqual(deque('abc', maxlen=2).maxlen, 2) self.assertEqual(deque('abc', maxlen=0).maxlen, 0) with self.assertRaises(AttributeError): d = deque('abc') d.maxlen = 10 def test_count(self): for s in ('', 'abracadabra', 'simsalabim'*500+'abc'): s = list(s) d = deque(s) for letter in 'abcdefghijklmnopqrstuvwxyz': self.assertEqual(s.count(letter), d.count(letter), (s, d, letter)) self.assertRaises(TypeError, d.count) # too few args self.assertRaises(TypeError, d.count, 1, 2) # too many args class BadCompare: def __eq__(self, other): raise ArithmeticError d = deque([1, 2, BadCompare(), 3]) self.assertRaises(ArithmeticError, d.count, 2) d = deque([1, 2, 3]) self.assertRaises(ArithmeticError, d.count, BadCompare()) class MutatingCompare: def __eq__(self, other): self.d.pop() return True m = MutatingCompare() d = deque([1, 2, 3, m, 4, 5]) m.d = d self.assertRaises(RuntimeError, d.count, 3) # test issue11004 # block advance failed after rotation aligned elements on right side of block d = deque([None]*16) for i in range(len(d)): d.rotate(-1) d.rotate(1) self.assertEqual(d.count(1), 0) self.assertEqual(d.count(None), 16) def test_comparisons(self): d = deque('xabc'); d.popleft() for e in [d, deque('abc'), deque('ab'), deque(), list(d)]: self.assertEqual(d==e, type(d)==type(e) and list(d)==list(e)) self.assertEqual(d!=e, not(type(d)==type(e) and list(d)==list(e))) args = map(deque, ('', 'a', 'b', 'ab', 'ba', 'abc', 'xba', 'xabc', 'cba')) for x in args: for y in args: self.assertEqual(x == y, list(x) == list(y), (x,y)) self.assertEqual(x != y, list(x) != list(y), (x,y)) self.assertEqual(x < y, list(x) < list(y), (x,y)) self.assertEqual(x <= y, list(x) <= list(y), (x,y)) self.assertEqual(x > y, list(x) > list(y), (x,y)) self.assertEqual(x >= y, list(x) >= list(y), (x,y)) self.assertEqual(cmp(x,y), cmp(list(x),list(y)), (x,y)) def test_extend(self): d = deque('a') self.assertRaises(TypeError, d.extend, 1) d.extend('bcd') self.assertEqual(list(d), list('abcd')) d.extend(d) self.assertEqual(list(d), list('abcdabcd')) def test_iadd(self): d = deque('a') d += 'bcd' self.assertEqual(list(d), list('abcd')) d += d self.assertEqual(list(d), list('abcdabcd')) def test_extendleft(self): d = deque('a') self.assertRaises(TypeError, d.extendleft, 1) d.extendleft('bcd') self.assertEqual(list(d), list(reversed('abcd'))) d.extendleft(d) self.assertEqual(list(d), list('abcddcba')) d = deque() d.extendleft(range(1000)) self.assertEqual(list(d), list(reversed(range(1000)))) self.assertRaises(SyntaxError, d.extendleft, fail()) def test_getitem(self): n = 200 d = deque(xrange(n)) l = range(n) for i in xrange(n): d.popleft() l.pop(0) if random.random() < 0.5: d.append(i) l.append(i) for j in xrange(1-len(l), len(l)): assert d[j] == l[j] d = deque('superman') self.assertEqual(d[0], 's') self.assertEqual(d[-1], 'n') d = deque() self.assertRaises(IndexError, d.__getitem__, 0) self.assertRaises(IndexError, d.__getitem__, -1) def test_setitem(self): n = 200 d = deque(xrange(n)) for i in xrange(n): d[i] = 10 * i self.assertEqual(list(d), [10*i for i in xrange(n)]) l = list(d) for i in xrange(1-n, 0, -1): d[i] = 7*i l[i] = 7*i self.assertEqual(list(d), l) def test_delitem(self): n = 500 # O(n**2) test, don't make this too big d = deque(xrange(n)) self.assertRaises(IndexError, d.__delitem__, -n-1) self.assertRaises(IndexError, d.__delitem__, n) for i in xrange(n): self.assertEqual(len(d), n-i) j = random.randrange(-len(d), len(d)) val = d[j] self.assertIn(val, d) del d[j] self.assertNotIn(val, d) self.assertEqual(len(d), 0) def test_reverse(self): n = 500 # O(n**2) test, don't make this too big data = [random.random() for i in range(n)] for i in range(n): d = deque(data[:i]) r = d.reverse() self.assertEqual(list(d), list(reversed(data[:i]))) self.assertIs(r, None) d.reverse() self.assertEqual(list(d), data[:i]) self.assertRaises(TypeError, d.reverse, 1) # Arity is zero def test_rotate(self): s = tuple('abcde') n = len(s) d = deque(s) d.rotate(1) # verify rot(1) self.assertEqual(''.join(d), 'eabcd') d = deque(s) d.rotate(-1) # verify rot(-1) self.assertEqual(''.join(d), 'bcdea') d.rotate() # check default to 1 self.assertEqual(tuple(d), s) for i in xrange(n*3): d = deque(s) e = deque(d) d.rotate(i) # check vs. rot(1) n times for j in xrange(i): e.rotate(1) self.assertEqual(tuple(d), tuple(e)) d.rotate(-i) # check that it works in reverse self.assertEqual(tuple(d), s) e.rotate(n-i) # check that it wraps forward self.assertEqual(tuple(e), s) for i in xrange(n*3): d = deque(s) e = deque(d) d.rotate(-i) for j in xrange(i): e.rotate(-1) # check vs. rot(-1) n times self.assertEqual(tuple(d), tuple(e)) d.rotate(i) # check that it works in reverse self.assertEqual(tuple(d), s) e.rotate(i-n) # check that it wraps backaround self.assertEqual(tuple(e), s) d = deque(s) e = deque(s) e.rotate(BIG+17) # verify on long series of rotates dr = d.rotate for i in xrange(BIG+17): dr() self.assertEqual(tuple(d), tuple(e)) self.assertRaises(TypeError, d.rotate, 'x') # Wrong arg type self.assertRaises(TypeError, d.rotate, 1, 10) # Too many args d = deque() d.rotate() # rotate an empty deque self.assertEqual(d, deque()) def test_len(self): d = deque('ab') self.assertEqual(len(d), 2) d.popleft() self.assertEqual(len(d), 1) d.pop() self.assertEqual(len(d), 0) self.assertRaises(IndexError, d.pop) self.assertEqual(len(d), 0) d.append('c') self.assertEqual(len(d), 1) d.appendleft('d') self.assertEqual(len(d), 2) d.clear() self.assertEqual(len(d), 0) def test_underflow(self): d = deque() self.assertRaises(IndexError, d.pop) self.assertRaises(IndexError, d.popleft) def test_clear(self): d = deque(xrange(100)) self.assertEqual(len(d), 100) d.clear() self.assertEqual(len(d), 0) self.assertEqual(list(d), []) d.clear() # clear an emtpy deque self.assertEqual(list(d), []) def test_remove(self): d = deque('abcdefghcij') d.remove('c') self.assertEqual(d, deque('abdefghcij')) d.remove('c') self.assertEqual(d, deque('abdefghij')) self.assertRaises(ValueError, d.remove, 'c') self.assertEqual(d, deque('abdefghij')) # Handle comparison errors d = deque(['a', 'b', BadCmp(), 'c']) e = deque(d) self.assertRaises(RuntimeError, d.remove, 'c') for x, y in zip(d, e): # verify that original order and values are retained. self.assertTrue(x is y) # Handle evil mutator for match in (True, False): d = deque(['ab']) d.extend([MutateCmp(d, match), 'c']) self.assertRaises(IndexError, d.remove, 'c') self.assertEqual(d, deque()) def test_repr(self): d = deque(xrange(200)) e = eval(repr(d)) self.assertEqual(list(d), list(e)) d.append(d) self.assertIn('...', repr(d)) def test_print(self): d = deque(xrange(200)) d.append(d) test_support.unlink(test_support.TESTFN) fo = open(test_support.TESTFN, "wb") try: print >> fo, d, fo.close() fo = open(test_support.TESTFN, "rb") self.assertEqual(fo.read(), repr(d)) finally: fo.close() test_support.unlink(test_support.TESTFN) def test_init(self): self.assertRaises(TypeError, deque, 'abc', 2, 3); self.assertRaises(TypeError, deque, 1); def test_hash(self): self.assertRaises(TypeError, hash, deque('abc')) def test_long_steadystate_queue_popleft(self): for size in (0, 1, 2, 100, 1000): d = deque(xrange(size)) append, pop = d.append, d.popleft for i in xrange(size, BIG): append(i) x = pop() if x != i - size: self.assertEqual(x, i-size) self.assertEqual(list(d), range(BIG-size, BIG)) def test_long_steadystate_queue_popright(self): for size in (0, 1, 2, 100, 1000): d = deque(reversed(xrange(size))) append, pop = d.appendleft, d.pop for i in xrange(size, BIG): append(i) x = pop() if x != i - size: self.assertEqual(x, i-size) self.assertEqual(list(reversed(list(d))), range(BIG-size, BIG)) def test_big_queue_popleft(self): pass d = deque() append, pop = d.append, d.popleft for i in xrange(BIG): append(i) for i in xrange(BIG): x = pop() if x != i: self.assertEqual(x, i) def test_big_queue_popright(self): d = deque() append, pop = d.appendleft, d.pop for i in xrange(BIG): append(i) for i in xrange(BIG): x = pop() if x != i: self.assertEqual(x, i) def test_big_stack_right(self): d = deque() append, pop = d.append, d.pop for i in xrange(BIG): append(i) for i in reversed(xrange(BIG)): x = pop() if x != i: self.assertEqual(x, i) self.assertEqual(len(d), 0) def test_big_stack_left(self): d = deque() append, pop = d.appendleft, d.popleft for i in xrange(BIG): append(i) for i in reversed(xrange(BIG)): x = pop() if x != i: self.assertEqual(x, i) self.assertEqual(len(d), 0) def test_roundtrip_iter_init(self): d = deque(xrange(200)) e = deque(d) self.assertNotEqual(id(d), id(e)) self.assertEqual(list(d), list(e)) def test_pickle(self): d = deque(xrange(200)) for i in range(pickle.HIGHEST_PROTOCOL + 1): s = pickle.dumps(d, i) e = pickle.loads(s) self.assertNotEqual(id(d), id(e)) self.assertEqual(list(d), list(e)) ## def test_pickle_recursive(self): ## d = deque('abc') ## d.append(d) ## for i in range(pickle.HIGHEST_PROTOCOL + 1): ## e = pickle.loads(pickle.dumps(d, i)) ## self.assertNotEqual(id(d), id(e)) ## self.assertEqual(id(e), id(e[-1])) def test_deepcopy(self): mut = [10] d = deque([mut]) e = copy.deepcopy(d) self.assertEqual(list(d), list(e)) mut[0] = 11 self.assertNotEqual(id(d), id(e)) self.assertNotEqual(list(d), list(e)) def test_copy(self): mut = [10] d = deque([mut]) e = copy.copy(d) self.assertEqual(list(d), list(e)) mut[0] = 11 self.assertNotEqual(id(d), id(e)) self.assertEqual(list(d), list(e)) def test_reversed(self): for s in ('abcd', xrange(2000)): self.assertEqual(list(reversed(deque(s))), list(reversed(s))) def test_gc_doesnt_blowup(self): import gc # This used to assert-fail in deque_traverse() under a debug # build, or run wild with a NULL pointer in a release build. d = deque() for i in xrange(100): d.append(1) gc.collect() def test_container_iterator(self): # Bug #3680: tp_traverse was not implemented for deque iterator objects class C(object): pass for i in range(2): obj = C() ref = weakref.ref(obj) if i == 0: container = deque([obj, 1]) else: container = reversed(deque([obj, 1])) obj.x = iter(container) del obj, container gc.collect() self.assertTrue(ref() is None, "Cycle was not collected") check_sizeof = test_support.check_sizeof @test_support.cpython_only def test_sizeof(self): BLOCKLEN = 62 basesize = test_support.calcobjsize('2P4PlP') blocksize = struct.calcsize('2P%dP' % BLOCKLEN) self.assertEqual(object.__sizeof__(deque()), basesize) check = self.check_sizeof check(deque(), basesize + blocksize) check(deque('a'), basesize + blocksize) check(deque('a' * (BLOCKLEN // 2)), basesize + blocksize) check(deque('a' * (BLOCKLEN // 2 + 1)), basesize + 2 * blocksize) check(deque('a' * (42 * BLOCKLEN)), basesize + 43 * blocksize) class TestVariousIteratorArgs(unittest.TestCase): def test_constructor(self): for s in ("123", "", range(1000), ('do', 1.2), xrange(2000,2200,5)): for g in (seq_tests.Sequence, seq_tests.IterFunc, seq_tests.IterGen, seq_tests.IterFuncStop, seq_tests.itermulti, seq_tests.iterfunc): self.assertEqual(list(deque(g(s))), list(g(s))) self.assertRaises(TypeError, deque, seq_tests.IterNextOnly(s)) self.assertRaises(TypeError, deque, seq_tests.IterNoNext(s)) self.assertRaises(ZeroDivisionError, deque, seq_tests.IterGenExc(s)) def test_iter_with_altered_data(self): d = deque('abcdefg') it = iter(d) d.pop() self.assertRaises(RuntimeError, it.next) def test_runtime_error_on_empty_deque(self): d = deque() it = iter(d) d.append(10) self.assertRaises(RuntimeError, it.next) class Deque(deque): pass class DequeWithBadIter(deque): def __iter__(self): raise TypeError class TestSubclass(unittest.TestCase): def test_basics(self): d = Deque(xrange(25)) d.__init__(xrange(200)) for i in xrange(200, 400): d.append(i) for i in reversed(xrange(-200, 0)): d.appendleft(i) self.assertEqual(list(d), range(-200, 400)) self.assertEqual(len(d), 600) left = [d.popleft() for i in xrange(250)] self.assertEqual(left, range(-200, 50)) self.assertEqual(list(d), range(50, 400)) right = [d.pop() for i in xrange(250)] right.reverse() self.assertEqual(right, range(150, 400)) self.assertEqual(list(d), range(50, 150)) d.clear() self.assertEqual(len(d), 0) def test_copy_pickle(self): d = Deque('abc') e = d.__copy__() self.assertEqual(type(d), type(e)) self.assertEqual(list(d), list(e)) e = Deque(d) self.assertEqual(type(d), type(e)) self.assertEqual(list(d), list(e)) for proto in range(pickle.HIGHEST_PROTOCOL + 1): s = pickle.dumps(d, proto) e = pickle.loads(s) self.assertNotEqual(id(d), id(e)) self.assertEqual(type(d), type(e)) self.assertEqual(list(d), list(e)) d = Deque('abcde', maxlen=4) e = d.__copy__() self.assertEqual(type(d), type(e)) self.assertEqual(list(d), list(e)) e = Deque(d) self.assertEqual(type(d), type(e)) self.assertEqual(list(d), list(e)) for proto in range(pickle.HIGHEST_PROTOCOL + 1): s = pickle.dumps(d, proto) e = pickle.loads(s) self.assertNotEqual(id(d), id(e)) self.assertEqual(type(d), type(e)) self.assertEqual(list(d), list(e)) ## def test_pickle(self): ## d = Deque('abc') ## d.append(d) ## ## e = pickle.loads(pickle.dumps(d)) ## self.assertNotEqual(id(d), id(e)) ## self.assertEqual(type(d), type(e)) ## dd = d.pop() ## ee = e.pop() ## self.assertEqual(id(e), id(ee)) ## self.assertEqual(d, e) ## ## d.x = d ## e = pickle.loads(pickle.dumps(d)) ## self.assertEqual(id(e), id(e.x)) ## ## d = DequeWithBadIter('abc') ## self.assertRaises(TypeError, pickle.dumps, d) def test_weakref(self): d = deque('gallahad') p = weakref.proxy(d) self.assertEqual(str(p), str(d)) d = None self.assertRaises(ReferenceError, str, p) def test_strange_subclass(self): class X(deque): def __iter__(self): return iter([]) d1 = X([1,2,3]) d2 = X([4,5,6]) d1 == d2 # not clear if this is supposed to be True or False, # but it used to give a SystemError class SubclassWithKwargs(deque): def __init__(self, newarg=1): deque.__init__(self) class TestSubclassWithKwargs(unittest.TestCase): def test_subclass_with_kwargs(self): # SF bug #1486663 -- this used to erroneously raise a TypeError SubclassWithKwargs(newarg=1) #============================================================================== libreftest = """ Example from the Library Reference: Doc/lib/libcollections.tex >>> from collections import deque >>> d = deque('ghi') # make a new deque with three items >>> for elem in d: # iterate over the deque's elements ... print elem.upper() G H I >>> d.append('j') # add a new entry to the right side >>> d.appendleft('f') # add a new entry to the left side >>> d # show the representation of the deque deque(['f', 'g', 'h', 'i', 'j']) >>> d.pop() # return and remove the rightmost item 'j' >>> d.popleft() # return and remove the leftmost item 'f' >>> list(d) # list the contents of the deque ['g', 'h', 'i'] >>> d[0] # peek at leftmost item 'g' >>> d[-1] # peek at rightmost item 'i' >>> list(reversed(d)) # list the contents of a deque in reverse ['i', 'h', 'g'] >>> 'h' in d # search the deque True >>> d.extend('jkl') # add multiple elements at once >>> d deque(['g', 'h', 'i', 'j', 'k', 'l']) >>> d.rotate(1) # right rotation >>> d deque(['l', 'g', 'h', 'i', 'j', 'k']) >>> d.rotate(-1) # left rotation >>> d deque(['g', 'h', 'i', 'j', 'k', 'l']) >>> deque(reversed(d)) # make a new deque in reverse order deque(['l', 'k', 'j', 'i', 'h', 'g']) >>> d.clear() # empty the deque >>> d.pop() # cannot pop from an empty deque Traceback (most recent call last): File "<pyshell#6>", line 1, in -toplevel- d.pop() IndexError: pop from an empty deque >>> d.extendleft('abc') # extendleft() reverses the input order >>> d deque(['c', 'b', 'a']) >>> def delete_nth(d, n): ... d.rotate(-n) ... d.popleft() ... d.rotate(n) ... >>> d = deque('abcdef') >>> delete_nth(d, 2) # remove the entry at d[2] >>> d deque(['a', 'b', 'd', 'e', 'f']) >>> def roundrobin(*iterables): ... pending = deque(iter(i) for i in iterables) ... while pending: ... task = pending.popleft() ... try: ... yield task.next() ... except StopIteration: ... continue ... pending.append(task) ... >>> for value in roundrobin('abc', 'd', 'efgh'): ... print value ... a d e b f c g h >>> def maketree(iterable): ... d = deque(iterable) ... while len(d) > 1: ... pair = [d.popleft(), d.popleft()] ... d.append(pair) ... return list(d) ... >>> print maketree('abcdefgh') [[[['a', 'b'], ['c', 'd']], [['e', 'f'], ['g', 'h']]]] """ #============================================================================== __test__ = {'libreftest' : libreftest} def test_main(verbose=None): import sys test_classes = ( TestBasic, TestVariousIteratorArgs, TestSubclass, TestSubclassWithKwargs, ) 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 # doctests from test import test_deque test_support.run_doctest(test_deque, verbose) if __name__ == "__main__": test_main(verbose=True) |