Unit testing the SharePoint API is impossible, difficult, easy

History:

• Before 2010 it was almost not possible.
• In 2010 it was possible by using a 3th party tool or Microsoft Research Pex & Moles (complex)
• In 2011-2012 the Pex and Moles team did a great job providing examples, white papers and behaviors to help SharePoint developers to unit test their code.
• Fakes are released with Visual Studio 2012
• SharePoint Emulators are released available !!!!!!!

Microsoft Research Pex & Moles – Moles examples

SPContext.Current.Web.Url

Uri url = new Uri(http://sp2010/test);
MSPContext.CurrentGet = () => new MSPContext() { 
    WebGet = () => new MSPWeb() {
        UrlGet = () => url.ToString()
    }  
};

SPDocumentLibrary

BSPSite site = new BSPSite();
site.Url = defaultviewUrl;
BSPWeb web = site.SetRootWeb();
MSPDocumentLibrary doclib = new MSPDocumentLibrary();
SPList splist = (SPDocumentLibrary)doclib;
web.Lists.SetOne(splist);
BSPList list = new BSPList(splist);
list.Views.DefaultViewIndex = 0;
BSPView view = list.Views.SetOne();
view.Url = site.Url;
MSPList mlist = new MSPList(splist);
mlist.ParentWebGet = () => web;

SPSecurity.RunWithElevatedPrivileges

MSPSecurity.RunWithElevatedPrivilegesSPSecurityCodeToRunElevated = f => f();

Cookies

MHttpContext.CurrentGet = () => new MHttpContext()
{
    RequestGet = () => new MHttpRequest()
    {
        CookiesGet = () => new MHttpCookieCollection()
        {
            ItemGetString = (s) => new MHttpCookie()
            {
                ValueGet = () => cookievalue
            }
        }
    },
    DisableCustomHttpEncoderGet = () => false
};

SharePoint Emulators

http://blogs.msdn.com/b/visualstudioalm/archive/2012/11/26/introducing-sharepoint-emulators.aspx