DemoStorage: update conflict resolution patch for ZODB 3.10

product/ERP5Type/patches/DemoStorage.py

 ##############################################################################
 #
 # Copyright (c) 2001, 2002 Zope Corporation and Contributors.
-# Copyright (c) 2010 Nexedi SARL and Contributors. All Rights Reserved.
-# All Rights Reserved.
+# Copyright (c) 2010-2013 Nexedi SARL and Contributors. All Rights Reserved.
 #
 # This software is subject to the provisions of the Zope Public License,
 # Version 2.1 (ZPL).  A copy of the ZPL should accompany this distribution.
@@ -13,43 +12,27 @@
 #
 ##############################################################################
 
-from ZODB.DemoStorage import DemoStorage
-from ZODB.ConflictResolution import tryToResolveConflict, ResolvedSerial
+from ZODB import DemoStorage as _DemoStorage
+from ZODB.ConflictResolution import ConflictResolvingStorage, ResolvedSerial
+from ZODB.POSException import ConflictError
 
-if 1:
+assert not issubclass(_DemoStorage.DemoStorage, ConflictResolvingStorage)
+
+class DemoStorage(_DemoStorage.DemoStorage, ConflictResolvingStorage):
     ##
     # Implement conflict resolution for DemoStorage
     #
-    import ZODB.POSException
 
     def store(self, oid, serial, data, version, transaction):
-        assert version=='', "versions aren't supported"
-        if transaction is not self._transaction:
-            raise ZODB.POSException.StorageTransactionError(self, transaction)
-
-        # Since the OID is being used, we don't have to keep up with it any
-        # more. Save it now so we can forget it later. :)
-        self._stored_oids.add(oid)
-
-        # See if we already have changes for this oid
         try:
-            old = self.changes.load(oid, '')[1]
-        except ZODB.POSException.POSKeyError:
-            try:
-                old = self.base.load(oid, '')[1]
-            except ZODB.POSException.POSKeyError:
-                old = serial
-                
-        if old != serial:
-            # <patch>
-            rdata = tryToResolveConflict(self, oid, old, serial, data)
-            if rdata is None:
-                raise ZODB.POSException.ConflictError(
-                    oid=oid, serials=(old, serial), data=data)
+            return super(DemoStorage, self).store(
+                oid, serial, data, version, transaction)
+        except ConflictError, e:
+            old = e.serials[0]
+            rdata = self.tryToResolveConflict(oid, old, serial, data)
+            if rdata is None: # BBB: Zope < 2.13
+                raise ConflictError(oid=oid, serials=(old, serial), data=data)
             self.changes.store(oid, old, rdata, '', transaction)
             return ResolvedSerial
-            # </patch>
-
-        return self.changes.store(oid, serial, data, '', transaction)
 
-    DemoStorage.store = store
+_DemoStorage.DemoStorage = DemoStorage