patch 8.0.1237: ":set scroll&" often gives an error commit https://github.com/vim/vim/commit/af2d20c6285c1d2973e3d9b5e8f727e3ed180493 Author: Bram Moolenaar <Bram@vim.org> Date: Sun Oct 29 15:26:57 2017 +0100 patch 8.0.1237: ":set scroll&" often gives an error Problem: ":set scroll&" often gives an error. Solution: Don't use a fixed default value, use half the window height. Add a test. (Ozaki Kiichi, closes #2104)

" Test feedkeys() function.

func Test_feedkeys_x_with_empty_string()
  new
  call feedkeys("ifoo\<Esc>")
  call assert_equal('', getline('.'))
  call feedkeys('', 'x')
  call assert_equal('foo', getline('.'))

  " check it goes back to normal mode immediately.
  call feedkeys('i', 'x')
  call assert_equal('foo', getline('.'))
  quit!
endfunc