anchor.diff:        request = {"args": {
           "action": "get_diff",
           "collection": "months",
  +        "version": 5,
           "args": args}
         };
   
  
positive.code: 
        //then
        verifyGeneratorCalledOnceWithArgs(args);
        dataProvider.getLogs(callsTo('remove')).verify(happenedOnce);
        expect(result, equals(dataProvider.futureMock));
      });
    });
  }
negative.code: 
        //then
        verifyGeneratorCalledOnceWithArgs(args);
        var callToDiff = dataProvider.getLogs(callsTo('change'));
        callToDiff.verify(happenedOnce);
        expect(callToDiff.first.args[0], equals(_id));
        expect(callToDiff.first.args[1], equals(data));
        expect(callToDiff.first.args[2], equals(author));
        expect(result, equals(dataProvider.responseFuture));
      });
  
      test("handle remove.", () {
  