patch 8.0.1293: setting a breakpoint in the terminal debugger sometimes fails commit https://github.com/vim/vim/commit/60e73f2acc890f07056fa1bea8dbe89d26918b3e Author: Bram Moolenaar <Bram@vim.org> Date: Sun Nov 12 18:02:06 2017 +0100 patch 8.0.1293: setting a breakpoint in the terminal debugger sometimes fails Problem: Setting a breakpoint in the terminal debugger sometimes fails. Solution: Interrupt the program if needed. Set the interface to async.

" Tests for the Tcl interface.

if !has('tcl')
  finish
end

function Test_tcldo()
  " Check deleting lines does not trigger ml_get error.
  new
  call setline(1, ['one', 'two', 'three'])
  tcldo ::vim::command %d_
  bwipe!

  " Check switching to another buffer does not trigger ml_get error.
  new
  let wincount = winnr('$')
  call setline(1, ['one', 'two', 'three'])
  tcldo ::vim::command new
  call assert_equal(wincount + 1, winnr('$'))
  bwipe!
  bwipe!
endfunc