import play.api.Play.current gives strange failures outside of a running app 

import play.api.Play.current gives strange failures outside of a running app.
Took me a bit of time to figure out during a training that a test that would not run used Webjars inside of a template. 

The rule of thumb is to avoid using play.api.Play.current  , especially in a static object. The reason is that if it fails it might give (as in my example) a very strange error message.