[Python-Dev] [Python-checkins] cpython: Issue #11707: Fast C version of functools.cmp_to_key()

[Victor Stinner]

I don't think that the following change conforms to the PEP 399: there
is only a test for the C version.

Victor

Le mardi 05 avril 2011 à 11:34 +0200, raymond.hettinger a écrit :
> http://hg.python.org/cpython/rev/a03fb2fc3ed8
> changeset:   69150:a03fb2fc3ed8
> user:        Raymond Hettinger <python at rcn.com>
> date:        Tue Apr 05 02:33:54 2011 -0700
> summary:
>   Issue #11707: Fast C version of functools.cmp_to_key()
> 
> diff --git a/Lib/test/test_functools.py b/Lib/test/test_functools.py
> --- a/Lib/test/test_functools.py
> +++ b/Lib/test/test_functools.py
> @@ -435,18 +435,81 @@
>          self.assertEqual(self.func(add, d), "".join(d.keys()))
>  
>  class TestCmpToKey(unittest.TestCase):
> +
>      def test_cmp_to_key(self):
> +        def cmp1(x, y):
> +            return (x > y) - (x < y)
> +        key = functools.cmp_to_key(cmp1)
> +        self.assertEqual(key(3), key(3))
> +        self.assertGreater(key(3), key(1))
> +        def cmp2(x, y):
> +            return int(x) - int(y)
> +        key = functools.cmp_to_key(cmp2)
> +        self.assertEqual(key(4.0), key('4'))
> +        self.assertLess(key(2), key('35'))
> +
> +    def test_cmp_to_key_arguments(self):
> +        def cmp1(x, y):
> +            return (x > y) - (x < y)
> +        key = functools.cmp_to_key(mycmp=cmp1)
> +        self.assertEqual(key(obj=3), key(obj=3))
> +        self.assertGreater(key(obj=3), key(obj=1))
> +        with self.assertRaises((TypeError, AttributeError)):
> +            key(3) > 1    # rhs is not a K object
> +        with self.assertRaises((TypeError, AttributeError)):
> +            1 < key(3)    # lhs is not a K object
> +        with self.assertRaises(TypeError):
> +            key = functools.cmp_to_key()             # too few args
> +        with self.assertRaises(TypeError):
> +            key = functools.cmp_to_key(cmp1, None)   # too many args
> +        key = functools.cmp_to_key(cmp1)
> +        with self.assertRaises(TypeError):
> +            key()                                    # too few args
> +        with self.assertRaises(TypeError):
> +            key(None, None)                          # too many args
> +
> +    def test_bad_cmp(self):
> +        def cmp1(x, y):
> +            raise ZeroDivisionError
> +        key = functools.cmp_to_key(cmp1)
> +        with self.assertRaises(ZeroDivisionError):
> +            key(3) > key(1)
> +
> +        class BadCmp:
> +            def __lt__(self, other):
> +                raise ZeroDivisionError
> +        def cmp1(x, y):
> +            return BadCmp()
> +        with self.assertRaises(ZeroDivisionError):
> +            key(3) > key(1)
> +
> +    def test_obj_field(self):
> +        def cmp1(x, y):
> +            return (x > y) - (x < y)
> +        key = functools.cmp_to_key(mycmp=cmp1)
> +        self.assertEqual(key(50).obj, 50)
> +
> +    def test_sort_int(self):
>          def mycmp(x, y):
>              return y - x
>          self.assertEqual(sorted(range(5), key=functools.cmp_to_key(mycmp)),
>                           [4, 3, 2, 1, 0])
>  
> +    def test_sort_int_str(self):
> +        def mycmp(x, y):
> +            x, y = int(x), int(y)
> +            return (x > y) - (x < y)
> +        values = [5, '3', 7, 2, '0', '1', 4, '10', 1]
> +        values = sorted(values, key=functools.cmp_to_key(mycmp))
> +        self.assertEqual([int(value) for value in values],
> +                         [0, 1, 1, 2, 3, 4, 5, 7, 10])
> +
>      def test_hash(self):
>          def mycmp(x, y):
>              return y - x
>          key = functools.cmp_to_key(mycmp)
>          k = key(10)
> -        self.assertRaises(TypeError, hash(k))
> +        self.assertRaises(TypeError, hash, k)