I'm writing Protractor/Jasmine E2E tests on a local machine in Visual Studio 2015 which has my project stored through TFS and then I am running those tests each night on another machine. I may be misunderstanding the concept here and/or missing the point of the appropriate tool for this situation.
But, is there a way such that when I check in changes on my local machine that those changes are automatically checked out (get latest) on the secondary machine without having to manually get latest on the files?
If you deploy a build agent on the second machine, when you queue build, build agent will get latest version of your project into the source directory.
Or as @jessehouwing mentioned in comment, you can use TF.exe command line in a script on your second machine to get latest version of your project:
tf get /version:T