public static FakeOrganzationService ExpectRetrieveMultipleOfApprovalRequest(
            this FakeOrganzationService service, ExpectRetrieveMultipleOfApprovalRequestResult expectedResult)
        {
            return(service.ExpectRetrieveMultiple(
                       query =>
            {
                var queryExpression = query as QueryExpression;
                Assert.IsNotNull(
                    queryExpression,
                    "Retrieve Multiple expected Query Expression and received something else.");


                switch (expectedResult)
                {
                case ExpectRetrieveMultipleOfApprovalRequestResult.NullResult:
                    return null;

                case ExpectRetrieveMultipleOfApprovalRequestResult.OneChild:
                    var result = new EntityCollection();
                    result.Entities.Add(new Entity(queryExpression.EntityName)
                    {
                        Id = Guid.NewGuid()
                    });
                    return result;

                case ExpectRetrieveMultipleOfApprovalRequestResult.NoChild:
                    return new EntityCollection();
                }

                return null;
            }));
        }