Using xCode 7 and xCtool.
xctool is capable of executing unit tests without the simulator.
To get this working,
1 . Update target settings to run without a host app.
Select your project –> then test target –> Set the host application to none.
2. Install xctool , if you don’t have it.
brew install xctool
3. Run the tests using terminal with xctool.
xctool -workspace yourWorkspace.xcworkspace -scheme yourScheme run-tests -sdk iphonesimulator