patch 8.0.1817: a timer may change v:count unexpectedly commit https://github.com/vim/vim/commit/b0f42ba60d9e6d101d103421ba0c351811615c15 Author: Bram Moolenaar <Bram@vim.org> Date: Sat May 12 15:38:26 2018 +0200 patch 8.0.1817: a timer may change v:count unexpectedly Problem: A timer may change v:count unexpectedly. Solution: Save and restore v:count and similar variables when a timer callback is invoked. (closes #2897)

" Test for :cd

func Test_cd_large_path()
  " This used to crash with a heap write overflow.
  call assert_fails('cd ' . repeat('x', 5000), 'E472:')
endfunc

func Test_cd_up_and_down()
  let path = getcwd()
  cd ..
  exe 'cd ' . path
  call assert_equal(path, getcwd())
endfunc