The highest language level available to me in RubyMine 5.4.2 is 1.9 which is grayed out when I select a 2.0.0-p247 SDK installed with RVM. Is this the expected behaviour? If yes, is RubyMine automatically detecting and using 2.0.0 syntax?
it is expected behavior for 5.4.2. In Momiji (6.0) (and as far as I remember in 5.4.3) there is language level 2.0