patch 8.1.2343: using time() for srand() is not very random Commit: https://github.com/vim/vim/commit/07e4a197953d12902fb97beb48830a5323a52280 Author: Bram Moolenaar <Bram@vim.org> Date: Tue Nov 26 12:23:30 2019 +0100 patch 8.1.2343: using time() for srand() is not very random Problem: Using time() for srand() is not very random. Solution: use /dev/urandom if available

" 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