Mailing List Archive

Update of /cvsroot/python/python/dist/src/Lib/test
In directory usw-pr-cvs1:/tmp/cvs-serv23330/Lib/test

Added Files:
test_enumerate.py
Log Message:
- New builtin function enumerate(x), from PEP 279. Example:
enumerate("abc") is an iterator returning (0,"a"), (1,"b"), (2,"c").
The argument can be an arbitrary iterable object.


--- NEW FILE: test_enumerate.py ---
from __future__ import generators
import unittest

import test_support

seq, res = 'abc', [(0,'a'), (1,'b'), (2,'c')]

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 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 N:
'Iterator missing next()'
def __init__(self, seqn):
self.seqn = seqn
self.i = 0
def __iter__(self):
return self

class EnumerateTestCase(unittest.TestCase):

enum = enumerate

def test_basicfunction(self):
self.assertEqual(type(self.enum(seq)), self.enum)
e = self.enum(seq)
self.assertEqual(iter(e), e)
self.assertEqual(list(self.enum(seq)), res)
self.enum.__doc__

def test_getitemseqn(self):
self.assertEqual(list(self.enum(G(seq))), res)
e = self.enum(G(''))
self.assertRaises(StopIteration, e.next)

def test_iteratorseqn(self):
self.assertEqual(list(self.enum(I(seq))), res)
e = self.enum(I(''))
self.assertRaises(StopIteration, e.next)

def test_iteratorgenerator(self):
self.assertEqual(list(self.enum(Ig(seq))), res)
e = self.enum(Ig(''))
self.assertRaises(StopIteration, e.next)

def test_noniterable(self):
self.assertRaises(TypeError, self.enum, X(seq))

def test_illformediterable(self):
self.assertRaises(TypeError, list, self.enum(N(seq)))

def test_exception_propagation(self):
self.assertRaises(ZeroDivisionError, list, self.enum(E(seq)))

class MyEnum(enumerate):
pass

class SubclassTestCase(EnumerateTestCase):

enum = MyEnum

def suite():
suite = unittest.TestSuite()
suite.addTest(unittest.makeSuite(EnumerateTestCase))
suite.addTest(unittest.makeSuite(SubclassTestCase))
return suite

def test_main():
test_support.run_suite(suite())

if __name__ == "__main__":
test_main()