From b4c20bfaa0464a68752a1c773212b96b6698f626 Mon Sep 17 00:00:00 2001
From: adustman <adustman@9fc6cd9a-920d-0410-adcf-ac96716ed7e8>
Date: Fri, 17 Oct 2008 00:44:48 +0000
Subject: [PATCH] Fix #2156977: Use frozenset as the base for DBAPISet. Only
 tested for Python 2.5.

---
 MySQLdb/MySQLdb/__init__.py | 35 +++++++++++++++++++++--------------
 1 file changed, 21 insertions(+), 14 deletions(-)

diff --git a/MySQLdb/MySQLdb/__init__.py b/MySQLdb/MySQLdb/__init__.py
index d06faa2..7bfac1d 100644
--- a/MySQLdb/MySQLdb/__init__.py
+++ b/MySQLdb/MySQLdb/__init__.py
@@ -31,25 +31,20 @@ from MySQLdb.constants import FIELD_TYPE
 from MySQLdb.times import Date, Time, Timestamp, \
     DateFromTicks, TimeFromTicks, TimestampFromTicks
 
-from sets import ImmutableSet
-class DBAPISet(ImmutableSet):
+try:
+    frozenset
+except NameError:
+    from sets import ImmutableSet as frozenset
+
+class DBAPISet(frozenset):
 
     """A special type of set for which A == x is true if A is a
     DBAPISet and x is a member of that set."""
 
-    def __ne__(self, other):
-        from sets import BaseSet
-        if isinstance(other, BaseSet):
-            return super(DBAPISet.self).__ne__(self, other)
-        else:
-            return other not in self
-
     def __eq__(self, other):
-        from sets import BaseSet
-        if isinstance(other, BaseSet):
-            return super(DBAPISet, self).__eq__(self, other)
-        else:
-            return other in self
+        if isinstance(other, DBAPISet):
+            return not self.difference(other)
+        return other in self
 
 
 STRING    = DBAPISet([FIELD_TYPE.ENUM, FIELD_TYPE.STRING,
@@ -65,6 +60,18 @@ TIMESTAMP = DBAPISet([FIELD_TYPE.TIMESTAMP, FIELD_TYPE.DATETIME])
 DATETIME  = TIMESTAMP
 ROWID     = DBAPISet()
 
+def test_DBAPISet_set_equality():
+    assert STRING == STRING
+
+def test_DBAPISet_set_inequality():
+    assert STRING != NUMBER
+
+def test_DBAPISet_set_equality_membership():
+    assert FIELD_TYPE.VAR_STRING == STRING
+
+def test_DBAPISet_set_inequality_membership():
+    assert FIELD_TYPE.DATE != STRING
+
 def Binary(x):
     return str(x)