[Python-checkins] python/dist/src/Lib/test test_itertools.py,1.9,1.10

rhettinger@users.sourceforge.net rhettinger@users.sourceforge.net
Fri, 02 May 2003 22:59:50 -0700


Update of /cvsroot/python/python/dist/src/Lib/test
In directory sc8-pr-cvs1:/tmp/cvs-serv31727/Lib/test

Modified Files:
	test_itertools.py 
Log Message:
* Added a substantial number of edge case and argument tests for
  the itertoolsmodule.
* Taught itertools.repeat(obj, n) to treat negative repeat counts as
  zero.  This behavior matches that for sequences and prevents 
  infinite loops.


Index: test_itertools.py
===================================================================
RCS file: /cvsroot/python/python/dist/src/Lib/test/test_itertools.py,v
retrieving revision 1.9
retrieving revision 1.10
diff -C2 -d -r1.9 -r1.10
*** test_itertools.py	2 May 2003 22:38:07 -0000	1.9
--- test_itertools.py	3 May 2003 05:59:48 -0000	1.10
***************
*** 3,10 ****
--- 3,38 ----
  from itertools import *
  import sys
+ import operator
+ 
+ def onearg(x):
+     'Test function of one argument'
+     return 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
+ 
+ class StopNow:
+     'Class emulating an empty iterable.'
+     def __iter__(self):
+         return self
+     def next(self):
+         raise StopIteration
  
  class TestBasicOps(unittest.TestCase):
      def test_chain(self):
          self.assertEqual(list(chain('abc', 'def')), list('abcdef'))
+         self.assertEqual(list(chain('abc')), list('abc'))
+         self.assertEqual(list(chain('')), [])
+         self.assertRaises(TypeError, chain, 2, 3)
  
      def test_count(self):
***************
*** 12,42 ****
          self.assertEqual(zip('abc',count(3)), [('a', 3), ('b', 4), ('c', 5)])
          self.assertRaises(TypeError, count, 2, 3)
  
      def test_cycle(self):
          self.assertEqual(list(islice(cycle('abc'),10)), list('abcabcabca'))
          self.assertEqual(list(cycle('')), [])
  
      def test_ifilter(self):
-         def isEven(x):
-             return x%2==0
          self.assertEqual(list(ifilter(isEven, range(6))), [0,2,4])
          self.assertEqual(list(ifilter(None, [0,1,0,2,0])), [1,2])
          self.assertRaises(TypeError, ifilter)
!         self.assertRaises(TypeError, ifilter, 3)
          self.assertRaises(TypeError, ifilter, isEven, 3)
  
      def test_ifilterfalse(self):
-         def isEven(x):
-             return x%2==0
          self.assertEqual(list(ifilterfalse(isEven, range(6))), [1,3,5])
          self.assertEqual(list(ifilterfalse(None, [0,1,0,2,0])), [0,0,0])
          self.assertRaises(TypeError, ifilterfalse)
!         self.assertRaises(TypeError, ifilterfalse, 3)
          self.assertRaises(TypeError, ifilterfalse, isEven, 3)
  
      def test_izip(self):
          ans = [(x,y) for x, y in izip('abc',count())]
          self.assertEqual(ans, [('a', 0), ('b', 1), ('c', 2)])
          self.assertRaises(TypeError, izip)
  
      def test_repeat(self):
--- 40,86 ----
          self.assertEqual(zip('abc',count(3)), [('a', 3), ('b', 4), ('c', 5)])
          self.assertRaises(TypeError, count, 2, 3)
+         self.assertRaises(TypeError, count, 'a')
+         c = count(sys.maxint-2)   # verify that rollover doesn't crash
+         c.next(); c.next(); c.next(); c.next(); c.next()
  
      def test_cycle(self):
          self.assertEqual(list(islice(cycle('abc'),10)), 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_ifilter(self):
          self.assertEqual(list(ifilter(isEven, range(6))), [0,2,4])
          self.assertEqual(list(ifilter(None, [0,1,0,2,0])), [1,2])
          self.assertRaises(TypeError, ifilter)
!         self.assertRaises(TypeError, ifilter, lambda x:x)
!         self.assertRaises(TypeError, ifilter, lambda x:x, range(6), 7)
          self.assertRaises(TypeError, ifilter, isEven, 3)
+         self.assertRaises(TypeError, ifilter(range(6), range(6)).next)
  
      def test_ifilterfalse(self):
          self.assertEqual(list(ifilterfalse(isEven, range(6))), [1,3,5])
          self.assertEqual(list(ifilterfalse(None, [0,1,0,2,0])), [0,0,0])
          self.assertRaises(TypeError, ifilterfalse)
!         self.assertRaises(TypeError, ifilterfalse, lambda x:x)
!         self.assertRaises(TypeError, ifilterfalse, lambda x:x, range(6), 7)
          self.assertRaises(TypeError, ifilterfalse, isEven, 3)
+         self.assertRaises(TypeError, ifilterfalse(range(6), range(6)).next)
  
      def test_izip(self):
          ans = [(x,y) for x, y in izip('abc',count())]
          self.assertEqual(ans, [('a', 0), ('b', 1), ('c', 2)])
+         self.assertEqual(list(izip('abc', range(6))), zip('abc', range(6)))
+         self.assertEqual(list(izip('abcdef', range(3))), zip('abcdef', range(3)))
+         self.assertEqual(list(izip('abcdef')), zip('abcdef'))
          self.assertRaises(TypeError, izip)
+         self.assertRaises(TypeError, izip, 3)
+         self.assertRaises(TypeError, izip, range(3), 3)
+         # Check tuple re-use (implementation detail)
+         self.assertEqual([tuple(list(pair)) for pair in izip('abc', 'def')],
+                          zip('abc', 'def'))
+         ids = map(id, izip('abc', 'def'))
+         self.assertEqual(min(ids), max(ids))
  
      def test_repeat(self):
***************
*** 44,63 ****
                           [(0, 'a'), (1, 'a'), (2, 'a')])
          self.assertEqual(list(repeat('a', 3)), ['a', 'a', 'a'])
          self.assertRaises(TypeError, repeat)
  
      def test_imap(self):
-         import operator
          self.assertEqual(list(imap(operator.pow, range(3), range(1,7))),
                           [0**1, 1**2, 2**3])
          self.assertEqual(list(imap(None, 'abc', range(5))),
                           [('a',0),('b',1),('c',2)])
          self.assertRaises(TypeError, imap)
          self.assertRaises(TypeError, imap, operator.neg)
  
      def test_starmap(self):
-         import operator
          self.assertEqual(list(starmap(operator.pow, zip(range(3), range(1,7)))),
                           [0**1, 1**2, 2**3])
          self.assertRaises(TypeError, list, starmap(operator.pow, [[4,5]]))
  
      def test_islice(self):
--- 88,119 ----
                           [(0, 'a'), (1, 'a'), (2, 'a')])
          self.assertEqual(list(repeat('a', 3)), ['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')
  
      def test_imap(self):
          self.assertEqual(list(imap(operator.pow, range(3), range(1,7))),
                           [0**1, 1**2, 2**3])
          self.assertEqual(list(imap(None, 'abc', range(5))),
                           [('a',0),('b',1),('c',2)])
+         self.assertEqual(list(imap(operator.pow, [])), [])
          self.assertRaises(TypeError, imap)
          self.assertRaises(TypeError, imap, operator.neg)
+         self.assertRaises(TypeError, imap(10, range(5)).next)
+         self.assertRaises(ValueError, imap(errfunc, [4], [5]).next)
+         self.assertRaises(TypeError, imap(onearg, [4], [5]).next)
  
      def test_starmap(self):
          self.assertEqual(list(starmap(operator.pow, zip(range(3), range(1,7)))),
                           [0**1, 1**2, 2**3])
+         self.assertEqual(list(starmap(operator.pow, [])), [])
          self.assertRaises(TypeError, list, starmap(operator.pow, [[4,5]]))
+         self.assertRaises(TypeError, starmap)
+         self.assertRaises(TypeError, starmap, operator.pow, [(4,5)], 'extra')
+         self.assertRaises(TypeError, starmap(10, [(4,5)]).next)
+         self.assertRaises(ValueError, starmap(errfunc, [(4,5)]).next)
+         self.assertRaises(TypeError, starmap(onearg, [(4,5)]).next)
  
      def test_islice(self):
***************
*** 101,104 ****
--- 157,166 ----
          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, takewhile(10, [(4,5)]).next)
+         self.assertRaises(ValueError, takewhile(errfunc, [(4,5)]).next)
  
      def test_dropwhile(self):
***************
*** 106,118 ****
          underten = lambda x: x<10
          self.assertEqual(list(dropwhile(underten, data)), [20, 2, 4, 6, 8])
  
      def test_StopIteration(self):
-         class StopNow:
-             """Test support class .  Emulates an empty iterable."""
-             def __iter__(self):
-                 return self
-             def next(self):
-                 raise StopIteration
- 
          for f in (chain, cycle, izip):
              self.assertRaises(StopIteration, f([]).next)
--- 168,179 ----
          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, dropwhile(10, [(4,5)]).next)
+         self.assertRaises(ValueError, dropwhile(errfunc, [(4,5)]).next)
  
      def test_StopIteration(self):
          for f in (chain, cycle, izip):
              self.assertRaises(StopIteration, f([]).next)