patch 8.1.1844: buffer no longer unloaded when adding text properties commit https://github.com/vim/vim/commit/45311b5274a6ac6e44235dfd4588c6b1bf0d4850 Author: Bram Moolenaar <Bram@vim.org> Date: Tue Aug 13 22:27:32 2019 +0200 patch 8.1.1844: buffer no longer unloaded when adding text properties Problem: Buffer no longer unloaded when adding text properties to it. Solution: Do not create the memfile. (closes https://github.com/vim/vim/issues/4808)

" Test if fnameescape is correct for special chars like !
func Test_fnameescape()
  let fname = 'Xspa ce'
  let status = v:false
  try
    exe "w! " . fnameescape(fname)
    let status = v:true
  endtry
  call assert_true(status, "Space")
  call delete(fname)

  let fname = 'Xemark!'
  let status = v:false
  try
    exe "w! " . fnameescape(fname)
    let status = v:true
  endtry
  call assert_true(status, "ExclamationMark")
  call delete(fname)
endfunc