Adding assertItemsEqual with tests. Issue 7832. assertSameElements still needs to be deprecated plus documentation needs to be updated.

Lib/unittest/case.py

@@ -838,6 +838,44 @@ class TestCase(object):
             standardMsg = '\n'.join(errors)
             self.fail(self._formatMessage(msg, standardMsg))
 
+
+    def assertItemsEqual(self, expected_seq, actual_seq, msg=None):
+        """An unordered sequence / set specific comparison. It asserts that
+        expected_seq and actual_seq contain the same elements. It is
+        the equivalent of::
+
+            self.assertEqual(sorted(expected_seq), sorted(actual_seq))
+
+        Raises with an error message listing which elements of expected_seq
+        are missing from actual_seq and vice versa if any.
+
+        Asserts that each element has the same count in both sequences.
+        Example:
+            - [0, 1, 1] and [1, 0, 1] compare equal.
+            - [0, 0, 1] and [0, 1] compare unequal.
+        """
+        try:
+            expected = sorted(expected_seq)
+            actual = sorted(actual_seq)
+        except TypeError:
+            # Unsortable items (example: set(), complex(), ...)
+            expected = list(expected_seq)
+            actual = list(actual_seq)
+            missing, unexpected = unorderable_list_difference(expected, actual)
+        else:
+            return self.assertSequenceEqual(expected, actual, msg=msg)
+
+        errors = []
+        if missing:
+            errors.append('Expected, but missing:\n    %s' %
+                           safe_repr(missing))
+        if unexpected:
+            errors.append('Unexpected, but present:\n    %s' %
+                           safe_repr(unexpected))
+        if errors:
+            standardMsg = '\n'.join(errors)
+            self.fail(self._formatMessage(msg, standardMsg))
+
     def assertMultiLineEqual(self, first, second, msg=None):
         """Assert that two multi-line strings are equal."""
         self.assert_(isinstance(first, str), (