commit https://github.com/vim/vim/commit/885f24fbcae2a39ae496ffb3a1e139379be8fae1 Author: Bram Moolenaar <Bram@vim.org> Date: Mon Feb 1 22:54:46 2016 +0100 patch 7.4.1236 Problem: When "syntax manual" was used switching between buffers removes the highlighting. Solution: Set the syntax option without changing the value. (Anton Lindqvist)

Test for ":options".

STARTTEST
:so small.vim
:let caught = 'ok'
:try
  :options
:catch 
  :let caught = v:throwpoint . "\n" . v:exception
:endtry
:buf 1
:$put =caught
:"
:" Test that changing 'path' keeps two commas.
:set path=foo,,bar
:set path-=bar
:set path+=bar
:$put =&path
:/^result/,$w! test.out
:qa!
ENDTEST

result