How to reset Thread.CurrentPrincipal to unauthenticated in a Unit Test

Question

I have library code that may be called from multiple client types such as WinForms, Console, ASP.NET etc... and which needs to determine the current principal. In doing so I am performing a two step check of Thread.CurrentPrincipal and then Environment.UserName as follows:

var currentUser = !System.Threading.Thread.CurrentPrincipal.Identity.IsAuthenticated ? null : System.Threading.Thread.CurrentPrincipal.Identity.Name;
if (string.IsNullOrWhiteSpace(currentUser))
{
    currentUser = Environment.UserName;
}

In a Console app Thread.CurrentPrincipal.Identity.IsAuthenticated is always false howerver in MSTest it always has a valid authenticated user.

Is there anyway to reset the value of Thread.CurrentPrincipal in the unit test to unauthenticated to mimick the Console app?

Answer 1

All you need to do is:

Thread.CurrentPrincipal = new GenericPrincipal(new GenericIdentity(""), new string[0]);