web2py - Unit testing @auth.requires_login()

All,

I have created a unit test for my web2py app.

I mainly followed this slice: http://ift.tt/1zvC1LM

I can register and login users with tests.

I cannot however get around the problem of testing the auth.requires_login() decorator.

I run tests that log the user in, i can see the resultant changes to the test db in auth_events and auth_users, but attempts to open the index function result in redirect.

When I run the test with the @auth decorator removed and put a simple if statement to check if a user exists i.e. that i logged a user in. This shows that a user exists and the auth object is visible to the function.

Any help would be great.