commit https://github.com/vim/vim/commit/0239acb11fe4bfe9b525ea90b782759da5eb7704 Author: Bram Moolenaar <Bram@vim.org> Date: Mon Apr 11 21:02:54 2016 +0200 patch 7.4.1722 Problem: Crash when calling garbagecollect() after starting a job. Solution: Set the copyID on job and channel. (Hirohito Higashi, Ozaki Kiichi)

" 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