Issue #1717: Remove cmp. Stage 1: remove all uses of cmp and __cmp__ from

the standard library and tests.

Lib/collections.py

@@ -436,8 +436,6 @@ class UserList(MutableSequence):
     def __ge__(self, other): return self.data >= self.__cast(other)
     def __cast(self, other):
         return other.data if isinstance(other, UserList) else other
-    def __cmp__(self, other):
-        return cmp(self.data, self.__cast(other))
     def __contains__(self, item): return item in self.data
     def __len__(self): return len(self.data)
     def __getitem__(self, i): return self.data[i]

Lib/ctypes/test/test_libc.py

@@ -5,6 +5,10 @@ import _ctypes_test
 
 lib = CDLL(_ctypes_test.__file__)
 
+def three_way_cmp(x, y):
+    """Return -1 if x < y, 0 if x == y and 1 if x > y"""
+    return (x > y) - (x < y)
+
 class LibTest(unittest.TestCase):
     def test_sqrt(self):
         lib.my_sqrt.argtypes = c_double,
@@ -19,7 +23,7 @@ class LibTest(unittest.TestCase):
         lib.my_qsort.restype = None
 
         def sort(a, b):
-            return cmp(a[0], b[0])
+            return three_way_cmp(a[0], b[0])
 
         chars = create_string_buffer("spam, spam, and spam")
         lib.my_qsort(chars, len(chars)-1, sizeof(c_char), comparefunc(sort))

Lib/distutils/version.py

@@ -21,7 +21,7 @@ Every version number class implements the following interface:
     an equivalent string -- ie. one that will generate an equivalent
     version number instance)
   * __repr__ generates Python code to recreate the version number instance
-  * __cmp__ compares the current instance with either another instance
+  * _cmp compares the current instance with either another instance
     of the same class or a string (which will be parsed to an instance
     of the same class, thus must follow the same rules)
 """
@@ -32,7 +32,7 @@ class Version:
     """Abstract base class for version numbering classes.  Just provides
     constructor (__init__) and reproducer (__repr__), because those
     seem to be the same for all version numbering classes; and route
-    rich comparisons to __cmp__.
+    rich comparisons to _cmp.
     """
 
     def __init__ (self, vstring=None):
@@ -43,37 +43,37 @@ class Version:
         return "%s ('%s')" % (self.__class__.__name__, str(self))
 
     def __eq__(self, other):
-        c = self.__cmp__(other)
+        c = self._cmp(other)
         if c is NotImplemented:
             return c
         return c == 0
 
     def __ne__(self, other):
-        c = self.__cmp__(other)
+        c = self._cmp(other)
         if c is NotImplemented:
             return c
         return c != 0
 
     def __lt__(self, other):
-        c = self.__cmp__(other)
+        c = self._cmp(other)
         if c is NotImplemented:
             return c
         return c < 0
 
     def __le__(self, other):
-        c = self.__cmp__(other)
+        c = self._cmp(other)
         if c is NotImplemented:
             return c
         return c <= 0
 
     def __gt__(self, other):
-        c = self.__cmp__(other)
+        c = self._cmp(other)
         if c is NotImplemented:
             return c
         return c > 0
 
     def __ge__(self, other):
-        c = self.__cmp__(other)
+        c = self._cmp(other)
         if c is NotImplemented:
             return c
         return c >= 0
@@ -91,7 +91,7 @@ class Version:
 #                        (if not identical to) the string supplied to parse
 #    __repr__ (self)   - generate Python code to recreate
 #                        the instance
-#    __cmp__ (self, other) - compare two version numbers ('other' may
+#    _cmp (self, other) - compare two version numbers ('other' may
 #                        be an unparsed version string, or another
 #                        instance of your version class)
 
@@ -169,30 +169,39 @@ class StrictVersion (Version):
         return vstring
 
 
-    def __cmp__ (self, other):
+    def _cmp (self, other):
         if isinstance(other, str):
             other = StrictVersion(other)
 
-        compare = cmp(self.version, other.version)
+        if self.version != other.version:
-        if (compare == 0):              # have to compare prerelease
+            # numeric versions don't match
-
+            # prerelease stuff doesn't matter
-            # case 1: neither has prerelease; they're equal
+            if self.version < other.version:
-            # case 2: self has prerelease, other doesn't; other is greater
-            # case 3: self doesn't have prerelease, other does: self is greater
-            # case 4: both have prerelease: must compare them!
-
-            if (not self.prerelease and not other.prerelease):
-                return 0
-            elif (self.prerelease and not other.prerelease):
                 return -1
-            elif (not self.prerelease and other.prerelease):
+            else:
                 return 1
-            elif (self.prerelease and other.prerelease):
-                return cmp(self.prerelease, other.prerelease)
 
-        else:                           # numeric versions don't match --
+        # have to compare prerelease
-            return compare              # prerelease stuff doesn't matter
+        # case 1: neither has prerelease; they're equal
+        # case 2: self has prerelease, other doesn't; other is greater
+        # case 3: self doesn't have prerelease, other does: self is greater
+        # case 4: both have prerelease: must compare them!
 
+        if (not self.prerelease and not other.prerelease):
+            return 0
+        elif (self.prerelease and not other.prerelease):
+            return -1
+        elif (not self.prerelease and other.prerelease):
+            return 1
+        elif (self.prerelease and other.prerelease):
+            if self.prerelease == other.prerelease:
+                return 0
+            elif self.prerelease < other.prerelease:
+                return -1
+            else:
+                return 1
+        else:
+            assert False, "never get here"
 
 # end class StrictVersion
 
@@ -325,7 +334,7 @@ class LooseVersion (Version):
         return "LooseVersion ('%s')" % str(self)
 
 
-    def __cmp__ (self, other):
+    def _cmp (self, other):
         if isinstance(other, str):
             other = LooseVersion(other)
 

Lib/heapq.py

@@ -262,7 +262,7 @@ def _siftdown(heap, startpos, pos):
 #
 # Cutting the # of comparisons is important, since these routines have no
 # way to extract "the priority" from an array element, so that intelligence
-# is likely to be hiding in custom __cmp__ methods, or in array elements
+# is likely to be hiding in custom comparison methods, or in array elements
 # storing (priority, record) tuples.  Comparisons are thus potentially
 # expensive.
 #

Lib/locale.py

@@ -31,7 +31,7 @@ def _strcoll(a,b):
     """ strcoll(string,string) -> int.
         Compares two strings according to the locale.
     """
-    return cmp(a,b)
+    return (a > b) - (a < b)
 
 def _strxfrm(s):
     """ strxfrm(string) -> string.

Lib/pydoc.py

@@ -1643,7 +1643,7 @@ class Helper:
         'SPECIALMETHODS': ('specialnames', 'BASICMETHODS ATTRIBUTEMETHODS '
                            'CALLABLEMETHODS SEQUENCEMETHODS1 MAPPINGMETHODS '
                            'SEQUENCEMETHODS2 NUMBERMETHODS CLASSES'),
-        'BASICMETHODS': ('customization', 'cmp hash repr str SPECIALMETHODS'),
+        'BASICMETHODS': ('customization', 'hash repr str SPECIALMETHODS'),
         'ATTRIBUTEMETHODS': ('attribute-access', 'ATTRIBUTES SPECIALMETHODS'),
         'CALLABLEMETHODS': ('callable-types', 'CALLS SPECIALMETHODS'),
         'SEQUENCEMETHODS': ('sequence-types', 'SEQUENCES SEQUENCEMETHODS2 '

Lib/sqlite3/test/hooks.py

@@ -42,7 +42,7 @@ class CollationTests(unittest.TestCase):
     def CheckCreateCollationNotAscii(self):
         con = sqlite.connect(":memory:")
         try:
-            con.create_collation("collä", cmp)
+            con.create_collation("collä", lambda x, y: (x > y) - (x < y))
             self.fail("should have raised a ProgrammingError")
         except sqlite.ProgrammingError as e:
             pass
@@ -52,7 +52,7 @@ class CollationTests(unittest.TestCase):
             return
         def mycoll(x, y):
             # reverse order
-            return -cmp(x, y)
+            return -((x > y) - (x < y))
 
         con = sqlite.connect(":memory:")
         con.create_collation("mycoll", mycoll)
@@ -82,8 +82,8 @@ class CollationTests(unittest.TestCase):
         Verify that the last one is actually used.
         """
         con = sqlite.connect(":memory:")
-        con.create_collation("mycoll", cmp)
+        con.create_collation("mycoll", lambda x, y: (x > y) - (x < y))
-        con.create_collation("mycoll", lambda x, y: -cmp(x, y))
+        con.create_collation("mycoll", lambda x, y: -((x > y) - (x < y)))
         result = con.execute("""
             select x from (select 'a' as x union select 'b' as x) order by x collate mycoll
             """).fetchall()
@@ -96,7 +96,7 @@ class CollationTests(unittest.TestCase):
         to use it.
         """
         con = sqlite.connect(":memory:")
-        con.create_collation("mycoll", cmp)
+        con.create_collation("mycoll", lambda x, y: (x > y) - (x < y))
         con.create_collation("mycoll", None)
         try:
             con.execute("select 'a' as x union select 'b' as x order by x collate mycoll")

Lib/test/crashers/loosing_mro_ref.py

@@ -10,7 +10,7 @@ class MyKey(object):
     def __hash__(self):
         return hash('mykey')
 
-    def __cmp__(self, other):
+    def __eq__(self, other):
         # the following line decrefs the previous X.__mro__
         X.__bases__ = (Base2,)
         # trash all tuples of length 3, to make sure that the items of
@@ -18,7 +18,7 @@ class MyKey(object):
         z = []
         for i in range(1000):
             z.append((i, None, None))
-        return -1
+        return 0
 
 
 class Base(object):

Lib/test/list_tests.py

@@ -439,13 +439,24 @@ class CommonTest(seq_tests.CommonTest):
         self.assertRaises(TypeError, u.sort, 42, 42)
 
         def revcmp(a, b):
-            return cmp(b, a)
+            if a == b:
+                return 0
+            elif a < b:
+                return 1
+            else: # a > b
+                return -1
         u.sort(key=CmpToKey(revcmp))
         self.assertEqual(u, self.type2test([2,1,0,-1,-2]))
 
         # The following dumps core in unpatched Python 1.5:
         def myComparison(x,y):
-            return cmp(x%3, y%7)
+            xmod, ymod = x%3, y%7
+            if xmod == ymod:
+                return 0
+            elif xmod < ymod:
+                return -1
+            else: # xmod > ymod
+                return 1
         z = self.type2test(range(12))
         z.sort(key=CmpToKey(myComparison))
 
@@ -453,7 +464,12 @@ class CommonTest(seq_tests.CommonTest):
 
         def selfmodifyingComparison(x,y):
             z.append(1)
-            return cmp(x, y)
+            if x == y:
+                return 0
+            elif x < y:
+                return -1
+            else: # x > y
+                return 1
         self.assertRaises(ValueError, z.sort, key=CmpToKey(selfmodifyingComparison))
 
         self.assertRaises(TypeError, z.sort, 42, 42, 42, 42)

Lib/test/test_builtin.py

@@ -10,6 +10,7 @@ warnings.filterwarnings("ignore", "hex../oct.. of negative int",
                         FutureWarning, __name__)
 warnings.filterwarnings("ignore", "integer argument expected",
                         DeprecationWarning, "unittest")
+import builtins
 
 class Squares:
 
@@ -219,21 +220,9 @@ class BuiltinTest(unittest.TestCase):
         self.assertRaises((OverflowError, ValueError), chr, 2**32)
 
     def test_cmp(self):
-        self.assertEqual(cmp(-1, 1), -1)
+        # uncomment the following line once cmp has been removed
-        self.assertEqual(cmp(1, -1), 1)
+        #self.assert_(not hasattr(builtins, "cmp"))
-        self.assertEqual(cmp(1, 1), 0)
+        pass
-        # verify that circular objects are not handled
-        a = []; a.append(a)
-        b = []; b.append(b)
-        from collections import UserList
-        c = UserList(); c.append(c)
-        self.assertRaises(RuntimeError, cmp, a, b)
-        self.assertRaises(RuntimeError, cmp, b, c)
-        self.assertRaises(RuntimeError, cmp, c, a)
-        self.assertRaises(RuntimeError, cmp, a, c)
-       # okay, now break the cycles
-        a.pop(); b.pop(); c.pop()
-        self.assertRaises(TypeError, cmp)
 
     def test_compile(self):
         compile('print(1)\n', '', 'exec')
@@ -736,10 +725,6 @@ class BuiltinTest(unittest.TestCase):
             def __getitem__(self, index):
                 raise ValueError
         self.assertRaises(ValueError, min, BadSeq())
-        class BadNumber:
-            def __cmp__(self, other):
-                raise ValueError
-        self.assertRaises(TypeError, min, (42, BadNumber()))
 
         for stmt in (
             "min(key=int)",                 # no args

Lib/test/test_contains.py

@@ -56,31 +56,16 @@ class TestContains(unittest.TestCase):
             This class is designed to make sure that the contains code
             works when the list is modified during the check.
             """
-            aList = range(15)
+            aList = list(range(15))
-            def __cmp__(self, other):
+            def __eq__(self, other):
                 if other == 12:
                     self.aList.remove(12)
                     self.aList.remove(13)
                     self.aList.remove(14)
-                return 1
+                return 0
 
         self.assert_(Deviant1() not in Deviant1.aList)
 
-        class Deviant2:
-            """Behaves strangely when compared
-
-            This class raises an exception during comparison.  That in
-            turn causes the comparison to fail with a TypeError.
-            """
-            def __cmp__(self, other):
-                if other == 4:
-                    raise RuntimeError("gotcha")
-
-        try:
-            self.assert_(Deviant2() not in a)
-        except TypeError:
-            pass
-
     def test_nonreflexive(self):
         # containment and equality tests involving elements that are
         # not necessarily equal to themselves

Lib/test/test_copy.py

@@ -2,10 +2,14 @@
 
 import copy
 import copyreg
-
+from operator import le, lt, ge, gt, eq, ne
 import unittest
 from test import support
 
+order_comparisons = le, lt, ge, gt
+equality_comparisons = eq, ne
+comparisons = order_comparisons + equality_comparisons
+
 class TestCopy(unittest.TestCase):
 
     # Attempt full line coverage of copy.py from top to bottom
@@ -271,7 +275,8 @@ class TestCopy(unittest.TestCase):
         x = []
         x.append(x)
         y = copy.deepcopy(x)
-        self.assertRaises(RuntimeError, cmp, y, x)
+        for op in comparisons:
+            self.assertRaises(RuntimeError, op, y, x)
         self.assert_(y is not x)
         self.assert_(y[0] is y)
         self.assertEqual(len(y), 1)
@@ -287,7 +292,8 @@ class TestCopy(unittest.TestCase):
         x = ([],)
         x[0].append(x)
         y = copy.deepcopy(x)
-        self.assertRaises(RuntimeError, cmp, y, x)
+        for op in comparisons:
+            self.assertRaises(RuntimeError, op, y, x)
         self.assert_(y is not x)
         self.assert_(y[0] is not x[0])
         self.assert_(y[0][0] is y)
@@ -303,7 +309,10 @@ class TestCopy(unittest.TestCase):
         x = {}
         x['foo'] = x
         y = copy.deepcopy(x)
-        self.assertRaises(TypeError, cmp, y, x)
+        for op in order_comparisons:
+            self.assertRaises(TypeError, op, y, x)
+        for op in equality_comparisons:
+            self.assertRaises(RuntimeError, op, y, x)
         self.assert_(y is not x)
         self.assert_(y['foo'] is y)
         self.assertEqual(len(y), 1)

Lib/test/test_datetime.py

@@ -7,6 +7,8 @@ import os
 import pickle
 import unittest
 
+from operator import lt, le, gt, ge, eq, ne
+
 from test import support
 
 from datetime import MINYEAR, MAXYEAR
@@ -156,9 +158,6 @@ class HarmlessMixedComparison:
         self.assertRaises(TypeError, lambda: () > me)
         self.assertRaises(TypeError, lambda: () >= me)
 
-        self.assertRaises(TypeError, cmp, (), me)
-        self.assertRaises(TypeError, cmp, me, ())
-
 #############################################################################
 # timedelta tests
 
@@ -309,8 +308,6 @@ class TestTimeDelta(HarmlessMixedComparison, unittest.TestCase):
         self.failUnless(not t1 != t2)
         self.failUnless(not t1 < t2)
         self.failUnless(not t1 > t2)
-        self.assertEqual(cmp(t1, t2), 0)
-        self.assertEqual(cmp(t2, t1), 0)
 
         for args in (3, 3, 3), (2, 4, 4), (2, 3, 5):
             t2 = timedelta(*args)   # this is larger than t1
@@ -326,8 +323,6 @@ class TestTimeDelta(HarmlessMixedComparison, unittest.TestCase):
             self.failUnless(not t2 < t1)
             self.failUnless(not t1 >= t2)
             self.failUnless(not t2 <= t1)
-            self.assertEqual(cmp(t1, t2), -1)
-            self.assertEqual(cmp(t2, t1), 1)
 
         for badarg in OTHERSTUFF:
             self.assertEqual(t1 == badarg, False)
@@ -953,8 +948,6 @@ class TestDate(HarmlessMixedComparison, unittest.TestCase):
         self.failUnless(not t1 != t2)
         self.failUnless(not t1 < t2)
         self.failUnless(not t1 > t2)
-        self.assertEqual(cmp(t1, t2), 0)
-        self.assertEqual(cmp(t2, t1), 0)
 
         for args in (3, 3, 3), (2, 4, 4), (2, 3, 5):
             t2 = self.theclass(*args)   # this is larger than t1
@@ -970,8 +963,6 @@ class TestDate(HarmlessMixedComparison, unittest.TestCase):
             self.failUnless(not t2 < t1)
             self.failUnless(not t1 >= t2)
             self.failUnless(not t2 <= t1)
-            self.assertEqual(cmp(t1, t2), -1)
-            self.assertEqual(cmp(t2, t1), 1)
 
         for badarg in OTHERSTUFF:
             self.assertEqual(t1 == badarg, False)
@@ -999,8 +990,6 @@ class TestDate(HarmlessMixedComparison, unittest.TestCase):
         # But the ordering is undefined
         self.assertRaises(TypeError, lambda: our < 1)
         self.assertRaises(TypeError, lambda: 1 < our)
-        self.assertRaises(TypeError, cmp, our, 1)
-        self.assertRaises(TypeError, cmp, 1, our)
 
         # Repeat those tests with a different class
 
@@ -1014,8 +1003,6 @@ class TestDate(HarmlessMixedComparison, unittest.TestCase):
         self.assertEqual(their != our, True)
         self.assertRaises(TypeError, lambda: our < their)
         self.assertRaises(TypeError, lambda: their < our)
-        self.assertRaises(TypeError, cmp, our, their)
-        self.assertRaises(TypeError, cmp, their, our)
 
         # However, if the other class explicitly defines ordering
         # relative to our class, it is allowed to do so
@@ -1041,8 +1028,6 @@ class TestDate(HarmlessMixedComparison, unittest.TestCase):
         self.assertEqual(their != our, True)
         self.assertEqual(our < their, True)
         self.assertEqual(their < our, False)
-        self.assertEqual(cmp(our, their), -1)
-        self.assertEqual(cmp(their, our), 1)
 
     def test_bool(self):
         # All dates are considered true.
@@ -1440,8 +1425,6 @@ class TestDateTime(TestDate):
         self.failUnless(not t1 != t2)
         self.failUnless(not t1 < t2)
         self.failUnless(not t1 > t2)
-        self.assertEqual(cmp(t1, t2), 0)
-        self.assertEqual(cmp(t2, t1), 0)
 
         for i in range(len(args)):
             newargs = args[:]
@@ -1459,8 +1442,6 @@ class TestDateTime(TestDate):
             self.failUnless(not t2 < t1)
             self.failUnless(not t1 >= t2)
             self.failUnless(not t2 <= t1)
-            self.assertEqual(cmp(t1, t2), -1)
-            self.assertEqual(cmp(t2, t1), 1)
 
 
     # A helper for timestamp constructor tests.
@@ -1728,8 +1709,6 @@ class TestTime(HarmlessMixedComparison, unittest.TestCase):
         self.failUnless(not t1 != t2)
         self.failUnless(not t1 < t2)
         self.failUnless(not t1 > t2)
-        self.assertEqual(cmp(t1, t2), 0)
-        self.assertEqual(cmp(t2, t1), 0)
 
         for i in range(len(args)):
             newargs = args[:]
@@ -1747,8 +1726,6 @@ class TestTime(HarmlessMixedComparison, unittest.TestCase):
             self.failUnless(not t2 < t1)
             self.failUnless(not t1 >= t2)
             self.failUnless(not t2 <= t1)
-            self.assertEqual(cmp(t1, t2), -1)
-            self.assertEqual(cmp(t2, t1), 1)
 
         for badarg in OTHERSTUFF:
             self.assertEqual(t1 == badarg, False)
@@ -2122,9 +2099,10 @@ class TZInfoBase:
         d2 = base.replace(minute=11)
         for x in d0, d1, d2:
             for y in d0, d1, d2:
-                got = cmp(x, y)
+                for op in lt, le, gt, ge, eq, ne:
-                expected = cmp(x.minute, y.minute)
+                    got = op(x, y)
-                self.assertEqual(got, expected)
+                    expected = op(x.minute, y.minute)
+                    self.assertEqual(got, expected)
 
         # However, if they're different members, uctoffset is not ignored.
         # Note that a time can't actually have an operand-depedent offset,
@@ -2136,7 +2114,7 @@ class TZInfoBase:
             d2 = base.replace(minute=11, tzinfo=OperandDependentOffset())
             for x in d0, d1, d2:
                 for y in d0, d1, d2:
-                    got = cmp(x, y)
+                    got = (x > y) - (x < y)
                     if (x is d0 or x is d1) and (y is d0 or y is d1):
                         expected = 0
                     elif x is y is d2:

Lib/test/test_decimal.py

@@ -1012,17 +1012,11 @@ class DecimalUsabilityTest(unittest.TestCase):
         self.failUnless(da != dc)
         self.failUnless(da <= db)
         self.failUnless(da >= db)
-        self.assertEqual(cmp(dc,da), 1)
-        self.assertEqual(cmp(da,dc), -1)
-        self.assertEqual(cmp(da,db), 0)
 
         #a Decimal and an int
         self.failUnless(dc > 23)
         self.failUnless(23 < dc)
         self.assertEqual(dc, 45)
-        self.assertEqual(cmp(dc,23), 1)
-        self.assertEqual(cmp(23,dc), -1)
-        self.assertEqual(cmp(dc,45), 0)
 
         #a Decimal and uncomparable
         self.assertNotEqual(da, 'ugly')

Lib/test/test_deque.py

@@ -103,7 +103,6 @@ class TestBasic(unittest.TestCase):
                 self.assertEqual(x <= y, list(x) <= list(y), (x,y))
                 self.assertEqual(x >  y, list(x) >  list(y), (x,y))
                 self.assertEqual(x >= y, list(x) >= list(y), (x,y))
-                self.assertEqual(cmp(x,y), cmp(list(x),list(y)), (x,y))
 
     def test_extend(self):
         d = deque('a')

Lib/test/test_descr.py

@@ -172,7 +172,6 @@ class OperatorsTest(unittest.TestCase):
 
     def test_dicts(self):
         # Testing dict operations...
-        ## self.binop_test({1:2}, {2:1}, -1, "cmp(a,b)", "__cmp__")
         self.binop_test({1:2,3:4}, 1, 1, "b in a", "__contains__")
         self.binop_test({1:2,3:4}, 2, 0, "b in a", "__contains__")
         self.binop_test({1:2,3:4}, 1, 2, "a[b]", "__getitem__")
@@ -332,8 +331,6 @@ class OperatorsTest(unittest.TestCase):
         # This is an ugly hack:
         copy._deepcopy_dispatch[spam.spamdict] = spamdict
 
-        ## self.binop_test(spamdict({1:2}), spamdict({2:1}), -1, "cmp(a,b)",
-        ##                 "__cmp__")
         self.binop_test(spamdict({1:2,3:4}), 1, 1, "b in a", "__contains__")
         self.binop_test(spamdict({1:2,3:4}), 2, 0, "b in a", "__contains__")
         self.binop_test(spamdict({1:2,3:4}), 1, 2, "a[b]", "__getitem__")
@@ -1004,8 +1001,8 @@ order (MRO) for bases """
         # Test lookup leaks [SF bug 572567]
         import sys,gc
         class G(object):
-            def __cmp__(self, other):
+            def __eq__(self, other):
-                return 0
+                return 1
         g = G()
         orig_objects = len(gc.get_objects())
         for i in range(10):
@@ -1525,7 +1522,6 @@ order (MRO) for bases """
         self.assertNotEqual(id(c1), id(c2))
         hash(c1)
         hash(c2)
-        ## self.assertEqual(cmp(c1, c2), cmp(id(c1), id(c2)))
         self.assertEqual(c1, c1)
         self.assert_(c1 != c2)
         self.assert_(not c1 != c1)
@@ -1549,7 +1545,6 @@ order (MRO) for bases """
         self.assertNotEqual(id(d1), id(d2))
         hash(d1)
         hash(d2)
-        ## self.assertEqual(cmp(d1, d2), cmp(id(d1), id(d2)))
         self.assertEqual(d1, d1)
         self.assertNotEqual(d1, d2)
         self.assert_(not d1 != d1)
@@ -1610,23 +1605,6 @@ order (MRO) for bases """
             self.assert_(i in p10)
         self.assertFalse(10 in p10)
 
-        ## # Safety test for __cmp__
-        ## def unsafecmp(a, b):
-        ##     try:
-        ##         a.__class__.__cmp__(a, b)
-        ##     except TypeError:
-        ##         pass
-        ##     else:
-        ##         self.fail("shouldn't allow %s.__cmp__(%r, %r)" % (
-        ##             a.__class__, a, b))
-        ##
-        ## unsafecmp("123", "123")
-        ## unsafecmp("123", "123")
-        ## unsafecmp(1, 1.0)
-        ## unsafecmp(1.0, 1)
-        ## unsafecmp(1, 1)
-        ## unsafecmp(1, 1)
-
     def test_weakrefs(self):
         # Testing weak references...
         import weakref
@@ -2538,12 +2516,16 @@ order (MRO) for bases """
             c = {1: c1, 2: c2, 3: c3}
             for x in 1, 2, 3:
                 for y in 1, 2, 3:
-                    ## self.assert_(cmp(c[x], c[y]) == cmp(x, y), "x=%d, y=%d" % (x, y))
                     for op in "<", "<=", "==", "!=", ">", ">=":
-                        self.assert_(eval("c[x] %s c[y]" % op) == eval("x %s y" % op),
+                        self.assert_(eval("c[x] %s c[y]" % op) ==
-                               "x=%d, y=%d" % (x, y))
+                                     eval("x %s y" % op),
-                    ## self.assert_(cmp(c[x], y) == cmp(x, y), "x=%d, y=%d" % (x, y))
+                                     "x=%d, y=%d" % (x, y))
-                    ## self.assert_(cmp(x, c[y]) == cmp(x, y), "x=%d, y=%d" % (x, y))
+                        self.assert_(eval("c[x] %s y" % op) ==
+                                     eval("x %s y" % op),
+                                     "x=%d, y=%d" % (x, y))
+                        self.assert_(eval("x %s c[y]" % op) ==
+                                     eval("x %s y" % op),
+                                     "x=%d, y=%d" % (x, y))
 
     def test_rich_comparisons(self):
         # Testing rich comparisons...

Lib/test/test_dict.py

@@ -570,7 +570,7 @@ class DictTest(unittest.TestCase):
             self.fail("missing KeyError")
 
     def test_bad_key(self):
-        # Dictionary lookups should fail if __cmp__() raises an exception.
+        # Dictionary lookups should fail if __eq__() raises an exception.
         class CustomException(Exception):
             pass
 

Lib/test/test_hash.py

@@ -55,13 +55,8 @@ class OnlyInequality(object):
     def __ne__(self, other):
         return self is not other
 
-class OnlyCmp(object):
-    def __cmp__(self, other):
-        return cmp(id(self), id(other))
-
 class InheritedHashWithEquality(FixedHash, OnlyEquality): pass
 class InheritedHashWithInequality(FixedHash, OnlyInequality): pass
-class InheritedHashWithCmp(FixedHash, OnlyCmp): pass
 
 class NoHash(object):
     __hash__ = None
@@ -74,7 +69,6 @@ class HashInheritanceTestCase(unittest.TestCase):
     fixed_expected = [FixedHash(),
                       InheritedHashWithEquality(),
                       InheritedHashWithInequality(),
-                      InheritedHashWithCmp(),
                       ]
     error_expected = [NoHash(),
                       OnlyEquality(),

Lib/test/test_heapq.py

@@ -234,9 +234,9 @@ class GetOnly:
 
 class CmpErr:
     "Dummy element that always raises an error during comparison"
-    def __cmp__(self, other):
+    def __eq__(self, other):
         raise ZeroDivisionError
-    __eq__ = __ne__ = __lt__ = __le__ = __gt__ = __ge__ = __cmp__
+    __ne__ = __lt__ = __le__ = __gt__ = __ge__ = __eq__
 
 def R(seqn):
     'Regular generator'

Lib/test/test_hmac.py

@@ -291,7 +291,7 @@ class CopyTestCase(unittest.TestCase):
         # Testing if the copy method created a real copy.
         h1 = hmac.HMAC(b"key")
         h2 = h1.copy()
-        # Using id() in case somebody has overridden __cmp__.
+        # Using id() in case somebody has overridden __eq__/__ne__.
         self.failUnless(id(h1) != id(h2), "No real copy of the HMAC instance.")
         self.failUnless(id(h1.inner) != id(h2.inner),
             "No real copy of the attribute 'inner'.")

Lib/test/test_kqueue.py

@@ -22,6 +22,7 @@ class TestKQueue(unittest.TestCase):
         self.assertRaises(ValueError, kq.fileno)
 
     def test_create_event(self):
+        from operator import lt, le, gt, ge
         fd = sys.stderr.fileno()
         ev = select.kevent(fd)
         other = select.kevent(1000)
@@ -33,12 +34,12 @@ class TestKQueue(unittest.TestCase):
         self.assertEqual(ev.udata, 0)
         self.assertEqual(ev, ev)
         self.assertNotEqual(ev, other)
-        self.assertEqual(cmp(ev, other), -1)
         self.assert_(ev < other)
         self.assert_(other >= ev)
-        self.assertRaises(TypeError, cmp, ev, None)
+        for op in lt, le, gt, ge:
-        self.assertRaises(TypeError, cmp, ev, 1)
+            self.assertRaises(TypeError, op, ev, None)
-        self.assertRaises(TypeError, cmp, ev, "ev")
+            self.assertRaises(TypeError, op, ev, 1)
+            self.assertRaises(TypeError, op, ev, "ev")
 
         ev = select.kevent(fd, select.KQ_FILTER_WRITE)
         self.assertEqual(ev.ident, fd)

Lib/test/test_long.py

@@ -697,7 +697,8 @@ class LongTest(unittest.TestCase):
             def _cmp__(self, other):
                 if not isinstance(other, Rat):
                     other = Rat(other)
-                return cmp(self.n * other.d, self.d * other.n)
+                x, y = self.n * other.d, self.d * other.n
+                return (x > y) - (x < y)
             def __eq__(self, other):
                 return self._cmp__(other) == 0
             def __ne__(self, other):
@@ -727,8 +728,8 @@ class LongTest(unittest.TestCase):
             Rx = Rat(x)
             for y in cases:
                 Ry = Rat(y)
-                Rcmp = cmp(Rx, Ry)
+                Rcmp = (Rx > Ry) - (Rx < Ry)
-                xycmp = cmp(x, y)
+                xycmp = (x > y) - (x < y)
                 eq(Rcmp, xycmp, Frm("%r %r %d %d", x, y, Rcmp, xycmp))
                 eq(x == y, Rcmp == 0, Frm("%r == %r %d", x, y, Rcmp))
                 eq(x != y, Rcmp != 0, Frm("%r != %r %d", x, y, Rcmp))

Lib/test/test_set.py

@@ -1036,16 +1036,6 @@ class TestBinaryOps(unittest.TestCase):
         result = self.set ^ set([8])
         self.assertEqual(result, set([2, 4, 6, 8]))
 
-    def test_cmp(self):
-        a, b = set('a'), set('b')
-        self.assertRaises(TypeError, cmp, a, b)
-
-        # In py3k, this works!
-        self.assertRaises(TypeError, cmp, a, a)
-
-        self.assertRaises(TypeError, cmp, a, 12)
-        self.assertRaises(TypeError, cmp, "abc", a)
-
 #==============================================================================
 
 class TestUpdateOps(unittest.TestCase):

Lib/test/test_sort.py

@@ -102,7 +102,7 @@ class TestBase(unittest.TestCase):
             y = x[:]
             y.reverse()
             s = x[:]
-            check("reversed via function", y, s, lambda a, b: cmp(b, a))
+            check("reversed via function", y, s, lambda a, b: (b>a)-(b<a))
 
             if verbose:
                 print("    Checking against an insane comparison function.")
@@ -157,13 +157,13 @@ class TestBugs(unittest.TestCase):
             def mutating_cmp(x, y):
                 L.append(3)
                 L.pop()
-                return cmp(x, y)
+                return (x > y) - (x < y)
             L = [1,2]
             self.assertRaises(ValueError, L.sort, key=CmpToKey(mutating_cmp))
             def mutating_cmp(x, y):
                 L.append(3)
                 del L[:]
-                return cmp(x, y)
+                return (x > y) - (x < y)
             self.assertRaises(ValueError, L.sort, key=CmpToKey(mutating_cmp))
             memorywaster = [memorywaster]
 
@@ -176,7 +176,10 @@ class TestDecorateSortUndecorate(unittest.TestCase):
         copy = data[:]
         random.shuffle(data)
         data.sort(key=str.lower)
-        copy.sort(key=CmpToKey(lambda x,y: cmp(x.lower(), y.lower())))
+        def my_cmp(x, y):
+            xlower, ylower = x.lower(), y.lower()
+            return (xlower > ylower) - (xlower < ylower)
+        copy.sort(key=CmpToKey(my_cmp))
 
     def test_baddecorator(self):
         data = 'The quick Brown fox Jumped over The lazy Dog'.split()
@@ -246,8 +249,14 @@ class TestDecorateSortUndecorate(unittest.TestCase):
         data = [(random.randrange(100), i) for i in range(200)]
         copy1 = data[:]
         copy2 = data[:]
-        data.sort(key=CmpToKey(lambda x,y: cmp(x[0],y[0])), reverse=True)
+        def my_cmp(x, y):
-        copy1.sort(key=CmpToKey(lambda x,y: cmp(y[0],x[0])))
+            x0, y0 = x[0], y[0]
+            return (x0 > y0) - (x0 < y0)
+        def my_cmp_reversed(x, y):
+            x0, y0 = x[0], y[0]
+            return (y0 > x0) - (y0 < x0)
+        data.sort(key=CmpToKey(my_cmp), reverse=True)
+        copy1.sort(key=CmpToKey(my_cmp_reversed))
         self.assertEqual(data, copy1)
         copy2.sort(key=lambda x: x[0], reverse=True)
         self.assertEqual(data, copy2)

Lib/test/test_unittest.py

@@ -1103,7 +1103,7 @@ class Test_TestLoader(TestCase):
     # getTestCaseNames() and all the loadTestsFromX() methods"
     def test_sortTestMethodsUsing__loadTestsFromTestCase(self):
         def reversed_cmp(x, y):
-            return -cmp(x, y)
+            return -((x > y) - (x < y))
 
         class Foo(unittest.TestCase):
             def test_1(self): pass
@@ -1119,7 +1119,7 @@ class Test_TestLoader(TestCase):
     # getTestCaseNames() and all the loadTestsFromX() methods"
     def test_sortTestMethodsUsing__loadTestsFromModule(self):
         def reversed_cmp(x, y):
-            return -cmp(x, y)
+            return -((x > y) - (x < y))
 
         m = types.ModuleType('m')
         class Foo(unittest.TestCase):
@@ -1137,7 +1137,7 @@ class Test_TestLoader(TestCase):
     # getTestCaseNames() and all the loadTestsFromX() methods"
     def test_sortTestMethodsUsing__loadTestsFromName(self):
         def reversed_cmp(x, y):
-            return -cmp(x, y)
+            return -((x > y) - (x < y))
 
         m = types.ModuleType('m')
         class Foo(unittest.TestCase):
@@ -1155,7 +1155,7 @@ class Test_TestLoader(TestCase):
     # getTestCaseNames() and all the loadTestsFromX() methods"
     def test_sortTestMethodsUsing__loadTestsFromNames(self):
         def reversed_cmp(x, y):
-            return -cmp(x, y)
+            return -((x > y) - (x < y))
 
         m = types.ModuleType('m')
         class Foo(unittest.TestCase):
@@ -1175,7 +1175,7 @@ class Test_TestLoader(TestCase):
     # Does it actually affect getTestCaseNames()?
     def test_sortTestMethodsUsing__getTestCaseNames(self):
         def reversed_cmp(x, y):
-            return -cmp(x, y)
+            return -((x > y) - (x < y))
 
         class Foo(unittest.TestCase):
             def test_1(self): pass
@@ -1188,9 +1188,19 @@ class Test_TestLoader(TestCase):
         self.assertEqual(loader.getTestCaseNames(Foo), test_names)
 
     # "The default value is the built-in cmp() function"
+    # Since cmp is now defunct, we simply verify that the results
+    # occur in the same order as they would with the default sort.
     def test_sortTestMethodsUsing__default_value(self):
         loader = unittest.TestLoader()
-        self.failUnless(loader.sortTestMethodsUsing is cmp)
+
+        class Foo(unittest.TestCase):
+            def test_2(self): pass
+            def test_3(self): pass
+            def test_1(self): pass
+
+        test_names = ['test_2', 'test_3', 'test_1']
+        self.assertEqual(loader.getTestCaseNames(Foo), sorted(test_names))
+
 
     # "it can be set to None to disable the sort."
     #

Lib/test/test_userdict.py

@@ -47,7 +47,7 @@ class UserDictTest(mapping_tests.TestHashMappingProtocol):
         self.assertEqual(repr(u1), repr(d1))
         self.assertEqual(repr(u2), repr(d2))
 
-        # Test __cmp__ and __len__
+        # Test rich comparison and __len__
         all = [d0, d1, d2, u, u0, u1, u2, uu, uu0, uu1, uu2]
         for a in all:
             for b in all:

Lib/test/test_uuid.py

@@ -181,7 +181,12 @@ class TestUUID(TestCase):
         # Test comparison of UUIDs.
         for i in range(len(ascending)):
             for j in range(len(ascending)):
-                equal(cmp(i, j), cmp(ascending[i], ascending[j]))
+                equal(i < j, ascending[i] < ascending[j])
+                equal(i <= j, ascending[i] <= ascending[j])
+                equal(i == j, ascending[i] == ascending[j])
+                equal(i > j, ascending[i] > ascending[j])
+                equal(i >= j, ascending[i] >= ascending[j])
+                equal(i != j, ascending[i] != ascending[j])
 
         # Test sorting of UUIDs (above list is in ascending order).
         resorted = ascending[:]

Lib/unittest.py

@@ -539,12 +539,16 @@ def CmpToKey(mycmp):
             return mycmp(self.obj, other.obj) == -1
     return K
 
+def three_way_cmp(x, y):
+    """Return -1 if x < y, 0 if x == y and 1 if x > y"""
+    return (x > y) - (x < y)
+
 class TestLoader(object):
     """This class is responsible for loading tests according to various
     criteria and returning them wrapped in a TestSuite
     """
     testMethodPrefix = 'test'
-    sortTestMethodsUsing = cmp
+    sortTestMethodsUsing = staticmethod(three_way_cmp)
     suiteClass = TestSuite
 
     def loadTestsFromTestCase(self, testCaseClass):

Lib/xml/dom/minidom.py

@@ -520,11 +520,29 @@ class NamedNodeMap(object):
 
     __len__ = _get_length
 
-    def __cmp__(self, other):
+    def _cmp(self, other):
         if self._attrs is getattr(other, "_attrs", None):
             return 0
         else:
-            return cmp(id(self), id(other))
+            return (id(self) > id(other)) - (id(self) < id(other))
+
+    def __eq__(self, other):
+        return self._cmp(other) == 0
+
+    def __ge__(self, other):
+        return self._cmp(other) >= 0
+
+    def __gt__(self, other):
+        return self._cmp(other) > 0
+
+    def __le__(self, other):
+        return self._cmp(other) <= 0
+
+    def __lt__(self, other):
+        return self._cmp(other) < 0
+
+    def __ne__(self, other):
+        return self._cmp(other) != 0
 
     def __getitem__(self, attname_or_tuple):
         if isinstance(attname_or_tuple, tuple):

Lib/xml/etree/ElementTree.py

@@ -498,10 +498,30 @@ class QName:
         return self.text
     def __hash__(self):
         return hash(self.text)
-    def __cmp__(self, other):
+    def __le__(self, other):
         if isinstance(other, QName):
-            return cmp(self.text, other.text)
+            return self.text <= other.text
-        return cmp(self.text, other)
+        return self.text <= other
+    def __lt__(self, other):
+        if isinstance(other, QName):
+            return self.text < other.text
+        return self.text < other
+    def __ge__(self, other):
+        if isinstance(other, QName):
+            return self.text >= other.text
+        return self.text >= other
+    def __gt__(self, other):
+        if isinstance(other, QName):
+            return self.text > other.text
+        return self.text > other
+    def __eq__(self, other):
+        if isinstance(other, QName):
+            return self.text == other.text
+        return self.text == other
+    def __ne__(self, other):
+        if isinstance(other, QName):
+            return self.text != other.text
+        return self.text != other
 
 ##
 # ElementTree wrapper class.  This class represents an entire element

Lib/xmlrpc/client.py

@@ -349,10 +349,6 @@ class DateTime:
     def timetuple(self):
         return time.strptime(self.value, "%Y%m%dT%H:%M:%S")
 
-    def __cmp__(self, other):
-        s, o = self.make_comparable(other)
-        return cmp(s, o)
-
     ##
     # Get date/time value.
     #

Tools/unicode/makeunicodedata.py

@@ -457,15 +457,6 @@ def makeunicodetype(unicode, trace):
 # --------------------------------------------------------------------
 # unicode name database
 
-def CmpToKey(mycmp):
-    'Convert a cmp= function into a key= function'
-    class K(object):
-        def __init__(self, obj, *args):
-            self.obj = obj
-        def __lt__(self, other):
-            return mycmp(self.obj, other.obj) == -1
-    return K
-
 def makeunicodename(unicode, trace):
 
     FILE = "Modules/unicodename_db.h"
@@ -508,14 +499,10 @@ def makeunicodename(unicode, trace):
     wordlist = list(words.items())
 
     # sort on falling frequency, then by name
-    def cmpwords(a,b):
+    def word_key(a):
         aword, alist = a
-        bword, blist = b
+        return -len(alist), aword
-        r = -cmp(len(alist),len(blist))
+    wordlist.sort(key=word_key)
-        if r:
-            return r
-        return cmp(aword, bword)
-    wordlist.sort(key=CmpToKey(cmpwords))
 
     # figure out how many phrasebook escapes we need
     escapes = 0