Unit Test a CSLA Asynchronous Validation Rule - unit-testing

Question

I have a validation rule on a CSLA Business Base stereotyped class. I'm having trouble figuring out how to unit test the validation rule as it includes an asynchronous callback lambda expression. Here's some example code:
using System;
using System.Collections.Generic;
using Csla;
using Csla.Validation;
namespace UnitTestCSLAAsyncValidationRule
{
public class BusinessObject : BusinessBase<BusinessObject>
{
protected static PropertyInfo<string> CodeProperty = RegisterProperty<string>(p => p.Code);
public string Code
{
get { return GetProperty(CodeProperty); }
set { SetProperty(CodeProperty, value); }
}
protected override void AddBusinessRules()
{
ValidationRules.AddRule(CodeValidator, new AsyncRuleArgs(CodeProperty));
}
public static void CodeValidator(AsyncValidationRuleContext context)
{
var code = (string) context.PropertyValues["Code"];
CodeList codeList;
CodeList.GetCodeList((o, l) =>
{
codeList = l.Object;
if (codeList.Contains(code))
{
context.OutArgs.Result = false;
context.OutArgs.Description = "Code already in use.";
}
else
{
context.OutArgs.Result = true;
}
});
context.Complete();
}
}
public class CodeList : List<string>
{
public static void GetCodeList(EventHandler<DataPortalResult<CodeList>> handler)
{
DataPortal<CodeList> dp = new DataPortal<CodeList>();
dp.FetchCompleted += handler;
dp.BeginFetch();
}
private void DataPortal_Fetch()
{
// some existing codes..
Add("123");
Add("456");
}
}
}
I would like to test this with a test similar to the following:
using NUnit.Framework;
namespace UnitTestCSLAAsyncValidationRule.Test
{
[TestFixture]
public class BusinessObjectTest
{
[Test]
public void CodeValidationTest()
{
var bo = new BusinessObject();
bo.Code = "123";
Assert.IsNotEmpty(bo.BrokenRulesCollection);
}
}
}
However, the test Assert runs before the async callback. Is this something UnitDriven could help with? I've had a look at it but can't see how to use it in this scenario.
Thanks,
Tom

Answer 1

Answered by JonnyBee on http://forums.lhotka.net/forums/p/10023/47030.aspx#47030:
using NUnit.Framework;
using UnitDriven;
namespace UnitTestCSLAAsyncValidationRule.Test
{
[TestFixture]
public class BusinessObjectTest : TestBase
{
[Test]
public void CodeValidationTest()
{
UnitTestContext context = GetContext();
var bo = new BusinessObject();
bo.ValidationComplete += (o, e) =>
{
context.Assert.IsFalse(bo.IsValid);
context.Assert.Success();
//Assert.IsNotEmpty(bo.BrokenRulesCollection);
};
bo.Code = "123";
context.Complete();
}
}
}
Please not there was a small bug in my validation rule method - the call to AsyncValidationRuleContext.Complete() needs to be inside the lambda.
Thanks,
Tom