forgot to add a file again...

src/ZODB/multicommitadapter.py

@@ -0,0 +1,65 @@
+"""Adapt non-IMultiCommitStorage storages to IMultiCommitStorage
+"""
+
+import zope.interface
+
+from .ConflictResolution import ResolvedSerial
+
+class MultiCommitAdapter:
+
+    def __init__(self, storage):
+        self._storage = storage
+        ifaces = zope.interface.providedBy(storage)
+        zope.interface.alsoProvides(self, ifaces)
+        self._resolved = set()
+
+    def __getattr__(self, name):
+        v = getattr(self._storage, name)
+        self.__dict__[name] = v
+        return v
+
+    def tpc_begin(self, *args):
+        self._storage.tpc_begin(*args)
+        self._resolved = set()
+
+    def store(self, oid, *args):
+        if self._storage.store(oid, *args) == ResolvedSerial:
+            self._resolved.add(oid)
+
+    def storeBlob(self, oid, *args):
+        s = self._storage.storeBlob(oid, *args)
+        if s:
+            if isinstance(s, bytes):
+                s = ((oid, s), )
+
+            for oid, serial in s:
+                if s == ResolvedSerial:
+                    self._resolved.add(oid)
+
+    def undo(self, transaction_id, transaction):
+        r = self._storage.undo(transaction_id, transaction)
+        if r:
+            self._resolved.update(set(r[1]))
+
+    def tpc_vote(self, *args):
+        s = self._storage.tpc_vote(*args)
+        for (oid, serial) in (s or ()):
+            if serial == ResolvedSerial:
+                self._resolved.add(oid)
+
+        return list(self._resolved)
+
+    def tpc_finish(self, transaction, f=lambda tid: None):
+
+        t = []
+
+        def func(tid):
+            t.append(tid)
+            f(tid)
+
+        self._storage.tpc_finish(transaction, func)
+
+        return t[0]
+
+    def __len__(self):
+        return len(self._storage)