commit https://github.com/vim/vim/commit/d4caf5c16a9f1c9477d426e58d8d3dc47ab5f066 Author: Bram Moolenaar <Bram@vim.org> Date: Thu Mar 24 19:14:35 2016 +0100 patch 7.4.1643 Problem: Terminating file name has side effects. Solution: Restore the character. (mostly by James McCoy, closes https://github.com/vim/vim/issues/713)

" Test for joining lines.

func Test_join_with_count()
  new
  call setline(1, ['one', 'two', 'three', 'four'])
  normal J
  call assert_equal('one two', getline(1))
  %del
  call setline(1, ['one', 'two', 'three', 'four'])
  normal 10J
  call assert_equal('one two three four', getline(1))
  quit!
endfunc