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Code Issues Projects Releases Packages Wiki Activity Actions 8

Issue #16148: implemented PEP 424

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This commit is contained in:
Armin Ronacher 2012-10-06 14:03:24 +02:00
parent ef08fb1f04
commit aa9a79d279
14 changed files with 161 additions and 82 deletions
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62
Lib/test/test_iterlen.py
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@ -45,31 +45,21 @@ import unittest
from test import support
from itertools import repeat
from collections import deque
from builtins import len as _len
from operator import length_hint
n = 10
def len(obj):
try:
return _len(obj)
except TypeError:
try:
# note: this is an internal undocumented API,
# don't rely on it in your own programs
return obj.__length_hint__()
except AttributeError:
raise TypeError
class TestInvariantWithoutMutations(unittest.TestCase):
def test_invariant(self):
it = self.it
for i in reversed(range(1, n+1)):
self.assertEqual(len(it), i)
self.assertEqual(length_hint(it), i)
next(it)
self.assertEqual(len(it), 0)
self.assertEqual(length_hint(it), 0)
self.assertRaises(StopIteration, next, it)
self.assertEqual(len(it), 0)
self.assertEqual(length_hint(it), 0)
class TestTemporarilyImmutable(TestInvariantWithoutMutations):
@ -78,12 +68,12 @@ class TestTemporarilyImmutable(TestInvariantWithoutMutations):
# length immutability during iteration
it = self.it
self.assertEqual(len(it), n)
self.assertEqual(length_hint(it), n)
next(it)
self.assertEqual(len(it), n-1)
self.assertEqual(length_hint(it), n-1)
self.mutate()
self.assertRaises(RuntimeError, next, it)
self.assertEqual(len(it), 0)
self.assertEqual(length_hint(it), 0)
## ------- Concrete Type Tests -------
@ -92,10 +82,6 @@ class TestRepeat(TestInvariantWithoutMutations):
def setUp(self):
self.it = repeat(None, n)
def test_no_len_for_infinite_repeat(self):
# The repeat() object can also be infinite
self.assertRaises(TypeError, len, repeat(None))
class TestXrange(TestInvariantWithoutMutations):
def setUp(self):
@ -167,14 +153,15 @@ class TestList(TestInvariantWithoutMutations):
it = iter(d)
next(it)
next(it)
self.assertEqual(len(it), n-2)
self.assertEqual(length_hint(it), n - 2)
d.append(n)
self.assertEqual(len(it), n-1) # grow with append
self.assertEqual(length_hint(it), n - 1) # grow with append
d[1:] = []
self.assertEqual(len(it), 0)
self.assertEqual(length_hint(it), 0)
self.assertEqual(list(it), [])
d.extend(range(20))
self.assertEqual(len(it), 0)
self.assertEqual(length_hint(it), 0)
class TestListReversed(TestInvariantWithoutMutations):
@ -186,32 +173,41 @@ class TestListReversed(TestInvariantWithoutMutations):
it = reversed(d)
next(it)
next(it)
self.assertEqual(len(it), n-2)
self.assertEqual(length_hint(it), n - 2)
d.append(n)
self.assertEqual(len(it), n-2) # ignore append
self.assertEqual(length_hint(it), n - 2) # ignore append
d[1:] = []
self.assertEqual(len(it), 0)
self.assertEqual(length_hint(it), 0)
self.assertEqual(list(it), []) # confirm invariant
d.extend(range(20))
self.assertEqual(len(it), 0)
self.assertEqual(length_hint(it), 0)
## -- Check to make sure exceptions are not suppressed by __length_hint__()
class BadLen(object):
def __iter__(self): return iter(range(10))
def __iter__(self):
return iter(range(10))
def __len__(self):
raise RuntimeError('hello')
class BadLengthHint(object):
def __iter__(self): return iter(range(10))
def __iter__(self):
return iter(range(10))
def __length_hint__(self):
raise RuntimeError('hello')
class NoneLengthHint(object):
def __iter__(self): return iter(range(10))
def __iter__(self):
return iter(range(10))
def __length_hint__(self):
return None
return NotImplemented
class TestLengthHintExceptions(unittest.TestCase):