patch 8.2.4728: no test that v:event cannot be modified Commit: https://github.com/vim/vim/commit/021996ffaa933d9dc0c3553ca01de93fbf3d522b Author: zeertzjq <zeertzjq@outlook.com> Date: Sun Apr 10 11:44:04 2022 +0100 patch 8.2.4728: no test that v:event cannot be modified Problem: No test that v:event cannot be modified. Solution: Add a test. (closes https://github.com/vim/vim/issues/10139)

" Simplistic way to make spaces and Tabs visible

" This can be added to an already active syntax.

syn match Space " "
syn match Tab "\t"
if &background == "dark"
  hi def Space ctermbg=darkred guibg=#500000
  hi def Tab ctermbg=darkgreen guibg=#003000
else
  hi def Space ctermbg=lightred guibg=#ffd0d0
  hi def Tab ctermbg=lightgreen guibg=#d0ffd0
endif