On Rails 5+, use rails as default 'makeprg'

Author: tpope

autoload/rails.vim

@@ -1440,7 +1440,7 @@ endfunction
 
 function! s:app_rake_command(...) dict abort
   let cmd = 'rake'
-  if self.has_rails5() && get(a:, 1, '') !=# 'norails' && get(g:, 'rails_make', '') ==# 'rails'
+  if self.has_rails5() && get(a:, 1, '') !=# 'norails' && get(g:, 'rails_make', '') !=# 'rake'
     let cmd = 'rails'
   endif
   if get(a:, 1, '') !=# 'static' && self.has_path('.zeus.sock') && executable('zeus')
@@ -5316,9 +5316,6 @@ function! rails#buffer_setup() abort
   endif
 
   compiler rails
-  if get(g:, 'rails_make', '') !=# 'rails'
-    let b:current_compiler = 'rake'
-  endif
   let &l:makeprg = self.app().rake_command('static')
   let &l:errorformat .= ',chdir '.escape(self.app().path(), ',')
 

doc/rails.txt

@@ -291,8 +291,8 @@ back out of any of the above commands.
 EXECUTABLE WRAPPERS				*rails-exec*
 
 Several commands are provided that wrap the `rails` and `rake` executables.
-Additionally, `rake` can be invoked directly with |:make| (or dispatch.vim's
-:Make).
+Additionally, `rails` (or `rake` on Rails versions older than 5) can be
+invoked directly with |:make| or dispatch.vim's :Make.
 
 						*rails-:Rails*
 :Rails {command} [options]