Honestly if Conor were alive, he'd tell you that you need to setup your test site using a sub-domain and not just a simple folder off the root.. It will look like this:

Live site: http://yourdomain.com
Test Site: http://testsite.yourdomain.com
I would agree.
Just to add my meagre experience, for many moons I was developing Zen Cart locally using an alias in the Apache config, so I would access my sites as
192.168.1.100/mytestsite.
It was only when I starting using the URI mapping that I was forced to do it "properly" and use virtual hosts and a redirect in my windows host files to use
www.mysite.local to access the local site. Otherwise the URI mapping was problematical.