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bigfile/_file_zodb.pyx

@@ -158,6 +158,13 @@ class ZSync:
 
     # DB.open() pops .zconn from connection pool and "opens" for usage.
     # -> resync .wconn to new database view of ZODB connection.
+    #
+    # FIXME zconn.at can change even without zconn.close/zconn.open, e.g.:
+    # zconn = DB.open(transaction_manager=tm)
+    # tm.commit()   # zconn.at updated          (zconn.afterCompletion -> zconn.newTransaction)
+    # tm.commit()   # zconn.at updated again
+    #
+    # TODO fix/test for that.
     def on_connection_open(zsync):
         print('ZSync.resync %r %r' % (zsync.zconn, zsync.wconn))
         zsync.wconn.resync(zconn_at(zsync.zconn))