ASP.NET MVC ActionResult Helper

Chris Canal — Thu, 15 May 2008 17:59:14 GMT

Recently I’ve been working a lot with the new ASP.NET MVC framework, with Preview 1 (bleh) and the interim drop, Pre-Preview 3?
The ActionResult is a fantastic addition, making the framework far easier to test. However, I noticed I was basically doing the same thing for each test:

[Test]

public void TestSomething()

{

var actionResult = controllerUT.Something() as RenderViewResult;

If ( actionResult == null )

Assert.Fail(“ActionResult was null.”);

Assert.That(actionResult.ViewName, Is.EqualTo(“ViewName”));

Assert.That(actionResult.ViewData, Is.Typeof(typeof(SomeClass)));

Assert.That(((SomeClass)actionResult.ViewData).SomeProperty, Is.EqualTo(123));

}

Basically asserting the view name, view data type and maybe asserting a property or two on the view data. In the spirit of treating the test code as a first class citizen I decided to refactor out the duplication. The resulting refactoring turned the above into the following:

[Test]

public void TestSomething()

{

controller.Something().AssertViewName(“ViewName”).AssertViewDataType<SomeClass>(c => Assert.That(c.SomeProperty, Is.EqualTo(123));

}

Which I personally think is alot nicer! Although I'm a little biased, so I thought I would share it and see what other people thought of it. Below is the code I came up with. Any and all suggestions (good or bad) are appreciated

namespace e4umsMN.Spec.Utils

{

using System;

using System.Web.Mvc;

using NUnit.Framework;

using NUnit.Framework.SyntaxHelpers;

internal static class ActionResultHelper

{

#region Public statics (6)

public static ActionResult AssertActionRedirect(this ActionResult actionResult, string actionName)

{

return actionResult.AssertNotNull<ActionRedirectResult>(arr => Assert.That(arr.Values["action"], Is.EqualTo(actionName)));

}

public static ActionResult AssertHttpRedirect(this ActionResult actionResult, string redirect)

{

return actionResult.AssertNotNull<HttpRedirectResult>(hrr => Assert.That(hrr.Url, Is.EqualTo(redirect)));

}

public static ActionResult AssertRenderViewResult(this ActionResult actonResult, Action<RenderViewResult> extraAssert)

{

return actonResult.AssertNotNull(extraAssert);

}

public static ActionResult AssertViewDataType<T>(this ActionResult actionResult, Action<T> viewDataAssert)

{

return actionResult.AssertRenderViewResult(a => viewDataAssert((T)a.ViewData));

}

public static ActionResult AssertViewDataType<T>(this ActionResult actionResult)

{

return actionResult.AssertRenderViewResult(a => Assert.That(a.ViewData, Is.TypeOf(typeof(T))));

}

public static ActionResult AssertViewName(this ActionResult actionResult, string viewName)

{

return actionResult.AssertRenderViewResult(a => Assert.That(a.ViewName, Is.EqualTo(viewName)));

}

#endregion Public statics

#region Other statics (1)

private static T AssertNotNull<T>(this object actionResult, Action<T> extraAssert)

{

if (actionResult == null)

Assert.Fail("ActionResult was null");

extraAssert((T) actionResult);

return (T) actionResult;

}

#endregion Other statics

}

}

Handy HttpPostedFile & HttpFileCollection abstractions

Chris Canal — Wed, 23 Apr 2008 19:18:43 GMT

I've just upgraded to the latest version interim drop of the MVC framework and MVC Contrib (which I can't seem to build from source using NAnt...). Everything appeared to be ok, except for one thing: a controller action that uploads a file was now throwing an error:

cannot convert from 'System.Web.HttpPostedFileBase' to 'System.Web.HttpPostedFile'

After a few seconds of confusion I quicky dawned on me that this might be a very good thing. A quick look at the System.Web.Abstractions confirmed my throughts, it now contained abstractions for HttpPostedFile and HttpFileCollection!

Color me happy, the only code I couldn't get covered was Actions that handled file uploads.

aspnetmvc

ASP.NET MVC ActionResult Helper

Handy HttpPostedFile & HttpFileCollection abstractions