commit https://github.com/vim/vim/commit/e59215c7dcae17b03daf39517560cfaa03314f5a Author: Bram Moolenaar <Bram@vim.org> Date: Sun Aug 14 19:08:45 2016 +0200 patch 7.4.2212 Problem: Mark " is not set when closing a window in another tab. (Guraga) Solution: Check all tabs for the window to be valid. (based on patch by Hirohito Higashi, closes https://github.com/vim/vim/issues/974)

" Tests for :undo

func Test_ex_undo()
  new ex-undo
  setlocal ul=10
  exe "normal ione\n\<Esc>"
  setlocal ul=10
  exe "normal itwo\n\<Esc>"
  setlocal ul=10
  exe "normal ithree\n\<Esc>"
  call assert_equal(4, line('$'))
  undo
  call assert_equal(3, line('$'))
  undo 1
  call assert_equal(2, line('$'))
  undo 0
  call assert_equal(1, line('$'))
  quit!
endfunc