commit https://github.com/vim/vim/commit/e9c07270031e312082604d3505650f185aa65948 Author: Bram Moolenaar <Bram@vim.org> Date: Wed Mar 30 20:50:46 2016 +0200 patch 7.4.1686 Problem: When running tests $HOME/.viminfo is written. (James McCoy) Solution: Add 'nviminfo' to the 'viminfo' option. (closes https://github.com/vim/vim/issues/722)

" 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