commit https://github.com/vim/vim/commit/6dbf66aa3e2197ce41f2b1cc7602bb9c15840548 Author: Bram Moolenaar <Bram@vim.org> Date: Thu Dec 1 21:32:32 2016 +0100 patch 8.0.0116 Problem: When reading English help and using CTRl-] the language from 'helplang' is used. Solution: Make help tag jumps keep the language. (Tatsuki, test by Hirohito Higashi, closes #1249)

" Vim filetype plugin file
" Language:	groovy
" Maintainer:	Justin M. Keyes <justinkz@gmail.com>
" Last Change:	2016 May 22

if exists('b:did_ftplugin')
  finish
endif
let b:did_ftplugin = 1

let s:cpo_save = &cpo
set cpo-=C

let b:undo_ftplugin = 'setlocal commentstring<'

setlocal commentstring=//%s

let &cpo = s:cpo_save
unlet s:cpo_save