mirror of
https://github.com/python/cpython.git
synced 2025-11-04 07:31:38 +00:00
744 lines
22 KiB
Python
744 lines
22 KiB
Python
from collections import deque
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import unittest
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from test import support, seq_tests
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import gc
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import weakref
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import copy
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import pickle
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from io import StringIO
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import random
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import os
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BIG = 100000
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def fail():
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raise SyntaxError
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yield 1
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class BadCmp:
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def __eq__(self, other):
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raise RuntimeError
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class MutateCmp:
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def __init__(self, deque, result):
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self.deque = deque
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self.result = result
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def __eq__(self, other):
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self.deque.clear()
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return self.result
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class TestBasic(unittest.TestCase):
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def test_basics(self):
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d = deque(range(-5125, -5000))
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d.__init__(range(200))
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for i in range(200, 400):
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d.append(i)
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for i in reversed(range(-200, 0)):
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d.appendleft(i)
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self.assertEqual(list(d), list(range(-200, 400)))
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self.assertEqual(len(d), 600)
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left = [d.popleft() for i in range(250)]
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self.assertEqual(left, list(range(-200, 50)))
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self.assertEqual(list(d), list(range(50, 400)))
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right = [d.pop() for i in range(250)]
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right.reverse()
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self.assertEqual(right, list(range(150, 400)))
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self.assertEqual(list(d), list(range(50, 150)))
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def test_maxlen(self):
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self.assertRaises(ValueError, deque, 'abc', -1)
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self.assertRaises(ValueError, deque, 'abc', -2)
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it = iter(range(10))
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d = deque(it, maxlen=3)
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self.assertEqual(list(it), [])
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self.assertEqual(repr(d), 'deque([7, 8, 9], maxlen=3)')
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self.assertEqual(list(d), [7, 8, 9])
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self.assertEqual(d, deque(range(10), 3))
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d.append(10)
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self.assertEqual(list(d), [8, 9, 10])
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d.appendleft(7)
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self.assertEqual(list(d), [7, 8, 9])
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d.extend([10, 11])
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self.assertEqual(list(d), [9, 10, 11])
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d.extendleft([8, 7])
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self.assertEqual(list(d), [7, 8, 9])
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d = deque(range(200), maxlen=10)
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d.append(d)
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support.unlink(support.TESTFN)
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fo = open(support.TESTFN, "w")
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try:
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fo.write(str(d))
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fo.close()
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fo = open(support.TESTFN, "r")
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self.assertEqual(fo.read(), repr(d))
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finally:
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fo.close()
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support.unlink(support.TESTFN)
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d = deque(range(10), maxlen=None)
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self.assertEqual(repr(d), 'deque([0, 1, 2, 3, 4, 5, 6, 7, 8, 9])')
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fo = open(support.TESTFN, "w")
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try:
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fo.write(str(d))
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fo.close()
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fo = open(support.TESTFN, "r")
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self.assertEqual(fo.read(), repr(d))
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finally:
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fo.close()
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support.unlink(support.TESTFN)
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def test_maxlen_zero(self):
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it = iter(range(100))
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deque(it, maxlen=0)
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self.assertEqual(list(it), [])
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it = iter(range(100))
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d = deque(maxlen=0)
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d.extend(it)
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self.assertEqual(list(it), [])
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it = iter(range(100))
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d = deque(maxlen=0)
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d.extendleft(it)
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self.assertEqual(list(it), [])
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def test_maxlen_attribute(self):
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self.assertEqual(deque().maxlen, None)
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self.assertEqual(deque('abc').maxlen, None)
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self.assertEqual(deque('abc', maxlen=4).maxlen, 4)
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self.assertEqual(deque('abc', maxlen=2).maxlen, 2)
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self.assertEqual(deque('abc', maxlen=0).maxlen, 0)
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with self.assertRaises(AttributeError):
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d = deque('abc')
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d.maxlen = 10
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def test_comparisons(self):
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d = deque('xabc'); d.popleft()
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for e in [d, deque('abc'), deque('ab'), deque(), list(d)]:
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self.assertEqual(d==e, type(d)==type(e) and list(d)==list(e))
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self.assertEqual(d!=e, not(type(d)==type(e) and list(d)==list(e)))
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args = map(deque, ('', 'a', 'b', 'ab', 'ba', 'abc', 'xba', 'xabc', 'cba'))
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for x in args:
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for y in args:
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self.assertEqual(x == y, list(x) == list(y), (x,y))
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self.assertEqual(x != y, list(x) != list(y), (x,y))
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self.assertEqual(x < y, list(x) < list(y), (x,y))
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self.assertEqual(x <= y, list(x) <= list(y), (x,y))
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self.assertEqual(x > y, list(x) > list(y), (x,y))
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self.assertEqual(x >= y, list(x) >= list(y), (x,y))
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def test_extend(self):
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d = deque('a')
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self.assertRaises(TypeError, d.extend, 1)
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d.extend('bcd')
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self.assertEqual(list(d), list('abcd'))
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d.extend(d)
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self.assertEqual(list(d), list('abcdabcd'))
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def test_iadd(self):
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d = deque('a')
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d += 'bcd'
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self.assertEqual(list(d), list('abcd'))
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d += d
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self.assertEqual(list(d), list('abcdabcd'))
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def test_extendleft(self):
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d = deque('a')
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self.assertRaises(TypeError, d.extendleft, 1)
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d.extendleft('bcd')
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self.assertEqual(list(d), list(reversed('abcd')))
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d.extendleft(d)
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self.assertEqual(list(d), list('abcddcba'))
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d = deque()
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d.extendleft(range(1000))
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self.assertEqual(list(d), list(reversed(range(1000))))
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self.assertRaises(SyntaxError, d.extendleft, fail())
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def test_getitem(self):
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n = 200
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d = deque(range(n))
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l = list(range(n))
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for i in range(n):
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d.popleft()
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l.pop(0)
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if random.random() < 0.5:
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d.append(i)
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l.append(i)
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for j in range(1-len(l), len(l)):
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assert d[j] == l[j]
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d = deque('superman')
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self.assertEqual(d[0], 's')
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self.assertEqual(d[-1], 'n')
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d = deque()
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self.assertRaises(IndexError, d.__getitem__, 0)
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self.assertRaises(IndexError, d.__getitem__, -1)
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def test_setitem(self):
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n = 200
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d = deque(range(n))
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for i in range(n):
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d[i] = 10 * i
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self.assertEqual(list(d), [10*i for i in range(n)])
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l = list(d)
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for i in range(1-n, 0, -1):
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d[i] = 7*i
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l[i] = 7*i
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self.assertEqual(list(d), l)
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def test_delitem(self):
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n = 500 # O(n**2) test, don't make this too big
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d = deque(range(n))
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self.assertRaises(IndexError, d.__delitem__, -n-1)
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self.assertRaises(IndexError, d.__delitem__, n)
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for i in range(n):
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self.assertEqual(len(d), n-i)
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j = random.randrange(-len(d), len(d))
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val = d[j]
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self.assertTrue(val in d)
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del d[j]
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self.assertTrue(val not in d)
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self.assertEqual(len(d), 0)
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def test_rotate(self):
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s = tuple('abcde')
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n = len(s)
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d = deque(s)
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d.rotate(1) # verify rot(1)
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self.assertEqual(''.join(d), 'eabcd')
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d = deque(s)
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d.rotate(-1) # verify rot(-1)
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self.assertEqual(''.join(d), 'bcdea')
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d.rotate() # check default to 1
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self.assertEqual(tuple(d), s)
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for i in range(n*3):
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d = deque(s)
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e = deque(d)
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d.rotate(i) # check vs. rot(1) n times
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for j in range(i):
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e.rotate(1)
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self.assertEqual(tuple(d), tuple(e))
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d.rotate(-i) # check that it works in reverse
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self.assertEqual(tuple(d), s)
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e.rotate(n-i) # check that it wraps forward
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self.assertEqual(tuple(e), s)
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for i in range(n*3):
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d = deque(s)
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e = deque(d)
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d.rotate(-i)
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for j in range(i):
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e.rotate(-1) # check vs. rot(-1) n times
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self.assertEqual(tuple(d), tuple(e))
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d.rotate(i) # check that it works in reverse
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self.assertEqual(tuple(d), s)
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e.rotate(i-n) # check that it wraps backaround
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self.assertEqual(tuple(e), s)
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d = deque(s)
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e = deque(s)
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e.rotate(BIG+17) # verify on long series of rotates
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dr = d.rotate
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for i in range(BIG+17):
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dr()
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self.assertEqual(tuple(d), tuple(e))
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self.assertRaises(TypeError, d.rotate, 'x') # Wrong arg type
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self.assertRaises(TypeError, d.rotate, 1, 10) # Too many args
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d = deque()
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d.rotate() # rotate an empty deque
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self.assertEqual(d, deque())
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def test_len(self):
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d = deque('ab')
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self.assertEqual(len(d), 2)
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d.popleft()
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self.assertEqual(len(d), 1)
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d.pop()
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self.assertEqual(len(d), 0)
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self.assertRaises(IndexError, d.pop)
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self.assertEqual(len(d), 0)
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d.append('c')
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self.assertEqual(len(d), 1)
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d.appendleft('d')
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self.assertEqual(len(d), 2)
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d.clear()
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self.assertEqual(len(d), 0)
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def test_underflow(self):
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d = deque()
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self.assertRaises(IndexError, d.pop)
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self.assertRaises(IndexError, d.popleft)
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def test_clear(self):
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d = deque(range(100))
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self.assertEqual(len(d), 100)
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d.clear()
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self.assertEqual(len(d), 0)
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self.assertEqual(list(d), [])
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d.clear() # clear an emtpy deque
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self.assertEqual(list(d), [])
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def test_remove(self):
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d = deque('abcdefghcij')
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d.remove('c')
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self.assertEqual(d, deque('abdefghcij'))
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d.remove('c')
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self.assertEqual(d, deque('abdefghij'))
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self.assertRaises(ValueError, d.remove, 'c')
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self.assertEqual(d, deque('abdefghij'))
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# Handle comparison errors
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d = deque(['a', 'b', BadCmp(), 'c'])
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e = deque(d)
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self.assertRaises(RuntimeError, d.remove, 'c')
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for x, y in zip(d, e):
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# verify that original order and values are retained.
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self.assertTrue(x is y)
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# Handle evil mutator
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for match in (True, False):
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d = deque(['ab'])
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d.extend([MutateCmp(d, match), 'c'])
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self.assertRaises(IndexError, d.remove, 'c')
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self.assertEqual(d, deque())
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def test_repr(self):
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d = deque(range(200))
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e = eval(repr(d))
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self.assertEqual(list(d), list(e))
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d.append(d)
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self.assertTrue('...' in repr(d))
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def test_print(self):
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d = deque(range(200))
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d.append(d)
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try:
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support.unlink(support.TESTFN)
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fo = open(support.TESTFN, "w")
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print(d, file=fo, end='')
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fo.close()
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fo = open(support.TESTFN, "r")
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self.assertEqual(fo.read(), repr(d))
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finally:
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fo.close()
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support.unlink(support.TESTFN)
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def test_init(self):
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self.assertRaises(TypeError, deque, 'abc', 2, 3);
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self.assertRaises(TypeError, deque, 1);
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def test_hash(self):
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self.assertRaises(TypeError, hash, deque('abc'))
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def test_long_steadystate_queue_popleft(self):
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for size in (0, 1, 2, 100, 1000):
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d = deque(range(size))
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append, pop = d.append, d.popleft
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for i in range(size, BIG):
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append(i)
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x = pop()
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if x != i - size:
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self.assertEqual(x, i-size)
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self.assertEqual(list(d), list(range(BIG-size, BIG)))
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def test_long_steadystate_queue_popright(self):
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for size in (0, 1, 2, 100, 1000):
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d = deque(reversed(range(size)))
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append, pop = d.appendleft, d.pop
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for i in range(size, BIG):
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append(i)
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x = pop()
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if x != i - size:
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self.assertEqual(x, i-size)
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self.assertEqual(list(reversed(list(d))),
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list(range(BIG-size, BIG)))
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def test_big_queue_popleft(self):
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pass
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d = deque()
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append, pop = d.append, d.popleft
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for i in range(BIG):
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append(i)
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for i in range(BIG):
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x = pop()
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if x != i:
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self.assertEqual(x, i)
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def test_big_queue_popright(self):
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d = deque()
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append, pop = d.appendleft, d.pop
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for i in range(BIG):
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append(i)
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for i in range(BIG):
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x = pop()
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if x != i:
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self.assertEqual(x, i)
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def test_big_stack_right(self):
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d = deque()
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append, pop = d.append, d.pop
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for i in range(BIG):
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append(i)
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for i in reversed(range(BIG)):
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x = pop()
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if x != i:
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self.assertEqual(x, i)
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self.assertEqual(len(d), 0)
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def test_big_stack_left(self):
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d = deque()
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append, pop = d.appendleft, d.popleft
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for i in range(BIG):
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append(i)
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for i in reversed(range(BIG)):
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x = pop()
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if x != i:
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self.assertEqual(x, i)
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self.assertEqual(len(d), 0)
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def test_roundtrip_iter_init(self):
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d = deque(range(200))
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e = deque(d)
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self.assertNotEqual(id(d), id(e))
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self.assertEqual(list(d), list(e))
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def test_pickle(self):
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d = deque(range(200))
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for i in range(pickle.HIGHEST_PROTOCOL + 1):
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s = pickle.dumps(d, i)
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e = pickle.loads(s)
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self.assertNotEqual(id(d), id(e))
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self.assertEqual(list(d), list(e))
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## def test_pickle_recursive(self):
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## d = deque('abc')
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## d.append(d)
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## for i in range(pickle.HIGHEST_PROTOCOL + 1):
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## e = pickle.loads(pickle.dumps(d, i))
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## self.assertNotEqual(id(d), id(e))
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## self.assertEqual(id(e), id(e[-1]))
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def test_deepcopy(self):
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mut = [10]
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d = deque([mut])
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e = copy.deepcopy(d)
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self.assertEqual(list(d), list(e))
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mut[0] = 11
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self.assertNotEqual(id(d), id(e))
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self.assertNotEqual(list(d), list(e))
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def test_copy(self):
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mut = [10]
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d = deque([mut])
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e = copy.copy(d)
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self.assertEqual(list(d), list(e))
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mut[0] = 11
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self.assertNotEqual(id(d), id(e))
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self.assertEqual(list(d), list(e))
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def test_reversed(self):
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for s in ('abcd', range(2000)):
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self.assertEqual(list(reversed(deque(s))), list(reversed(s)))
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def test_gc_doesnt_blowup(self):
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import gc
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# This used to assert-fail in deque_traverse() under a debug
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# build, or run wild with a NULL pointer in a release build.
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d = deque()
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for i in range(100):
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d.append(1)
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gc.collect()
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def test_container_iterator(self):
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# Bug #3680: tp_traverse was not implemented for deque iterator objects
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class C(object):
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pass
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for i in range(2):
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obj = C()
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ref = weakref.ref(obj)
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if i == 0:
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container = deque([obj, 1])
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else:
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container = reversed(deque([obj, 1]))
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obj.x = iter(container)
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del obj, container
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gc.collect()
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self.assertTrue(ref() is None, "Cycle was not collected")
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class TestVariousIteratorArgs(unittest.TestCase):
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def test_constructor(self):
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for s in ("123", "", range(1000), ('do', 1.2), range(2000,2200,5)):
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for g in (seq_tests.Sequence, seq_tests.IterFunc,
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seq_tests.IterGen, seq_tests.IterFuncStop,
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seq_tests.itermulti, seq_tests.iterfunc):
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self.assertEqual(list(deque(g(s))), list(g(s)))
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self.assertRaises(TypeError, deque, seq_tests.IterNextOnly(s))
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self.assertRaises(TypeError, deque, seq_tests.IterNoNext(s))
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self.assertRaises(ZeroDivisionError, deque, seq_tests.IterGenExc(s))
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def test_iter_with_altered_data(self):
|
|
d = deque('abcdefg')
|
|
it = iter(d)
|
|
d.pop()
|
|
self.assertRaises(RuntimeError, next, it)
|
|
|
|
def test_runtime_error_on_empty_deque(self):
|
|
d = deque()
|
|
it = iter(d)
|
|
d.append(10)
|
|
self.assertRaises(RuntimeError, next, it)
|
|
|
|
class Deque(deque):
|
|
pass
|
|
|
|
class DequeWithBadIter(deque):
|
|
def __iter__(self):
|
|
raise TypeError
|
|
|
|
class TestSubclass(unittest.TestCase):
|
|
|
|
def test_basics(self):
|
|
d = Deque(range(25))
|
|
d.__init__(range(200))
|
|
for i in range(200, 400):
|
|
d.append(i)
|
|
for i in reversed(range(-200, 0)):
|
|
d.appendleft(i)
|
|
self.assertEqual(list(d), list(range(-200, 400)))
|
|
self.assertEqual(len(d), 600)
|
|
|
|
left = [d.popleft() for i in range(250)]
|
|
self.assertEqual(left, list(range(-200, 50)))
|
|
self.assertEqual(list(d), list(range(50, 400)))
|
|
|
|
right = [d.pop() for i in range(250)]
|
|
right.reverse()
|
|
self.assertEqual(right, list(range(150, 400)))
|
|
self.assertEqual(list(d), list(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))
|
|
|
|
s = pickle.dumps(d)
|
|
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))
|
|
|
|
s = pickle.dumps(d)
|
|
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 next(task)
|
|
... 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,
|
|
)
|
|
|
|
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)
|
|
|
|
# doctests
|
|
from test import test_deque
|
|
support.run_doctest(test_deque, verbose)
|
|
|
|
if __name__ == "__main__":
|
|
test_main(verbose=True)
|