From: Philip Jenvey <pjenvey@underboss.org>
Date: Tue, 21 Jul 2009 00:47:03 +0000 (+0000)
Subject: ensure _BindParamClause hash codes are unique on Jython
X-Git-Tag: rel_0_6_6~97
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b6384551d46df94386ff01bf193a43815ed4f1d0;p=thirdparty%2Fsqlalchemy%2Fsqlalchemy.git

ensure _BindParamClause hash codes are unique on Jython
fixes #1475
---

diff --git a/lib/sqlalchemy/sql/expression.py b/lib/sqlalchemy/sql/expression.py
index 8cf6109cae..9eb2926e5b 100644
--- a/lib/sqlalchemy/sql/expression.py
+++ b/lib/sqlalchemy/sql/expression.py
@@ -2121,6 +2121,16 @@ class _BindParamClause(ColumnElement):
         d['value'] = v
         return d
 
+    def __hash__(self):
+        """Return a distinct hash code.
+
+        ColumnOperators have special equality comparisons which makes us
+        rely on _BindParamClauses having unique hash codes for use in
+        hash-based collections. Stock __hash__ doesn't guarantee unique
+        values, particularly on platforms with moving GCs.
+        """
+        return id(self)
+
     def __repr__(self):
         return "_BindParamClause(%r, %r, type_=%r)" % (
             self.key, self.value, self.type