Test for v:hlsearch     vim: set ft=vim :

STARTTEST
:" Last abc: Q
:so small.vim
:new
:call setline(1, repeat(['aaa'], 10))
:set hlsearch nolazyredraw
:let r=[]
:command -nargs=0 -bar AddR :call add(r, [screenattr(1, 1), v:hlsearch])
/aaa
:AddR
:nohlsearch
:AddR
:let v:hlsearch=1
:AddR
:let v:hlsearch=0
:AddR
:set hlsearch
:AddR
:let v:hlsearch=0
:AddR
n:AddR
:let v:hlsearch=0
:AddR
/
:AddR
:let r1=r[0][0]
:" I guess it is not guaranteed that screenattr outputs always the same character
:call map(r, 'v:val[1].":".(v:val[0]==r1?"highlighted":"not highlighted")')
:try
:   let v:hlsearch=[]
:catch
:   call add(r, matchstr(v:exception,'^Vim(let):E\d\+:'))
:endtry
:bwipeout!
:$put=r
:call garbagecollect(1)
:"
:/^start:/,$wq! test.out
:" vim: et ts=4 isk-=\:
:call getchar()
ENDTEST

start: