patch 9.0.0598: using negative array index with negative width window Commit: https://github.com/vim/vim/commit/8279af514ca7e5fd3c31cf13b0864163d1a0bfeb Author: Bram Moolenaar <Bram@vim.org> Date: Mon Sep 26 23:08:22 2022 +0100 patch 9.0.0598: using negative array index with negative width window Problem: Using negative array index with negative width window. Solution: Make sure the window width does not become negative.

" Settings for test script execution
" Always use "sh", don't use the value of "$SHELL".
set shell=sh

" Only when the +eval feature is present. 
if 1
  " While some tests overwrite $HOME to prevent them from polluting user files,
  " we need to remember the original value so that we can tell external systems
  " where to ask about their own user settings.
  let g:tester_HOME = $HOME
endif

source setup.vim