Tests for 'listchars' display with 'list' and :list

STARTTEST
:so small.vim
:let g:lines = []
:function GetScreenCharsForLine(lnum)
:  return join(map(range(1, virtcol('$')), 'nr2char(screenchar(a:lnum, v:val))'), '')
:endfunction
:nnoremap <expr> GG ":call add(g:lines, GetScreenCharsForLine(".screenrow()."))\<CR>"
:set listchars+=tab:>-,space:.,trail:<
:set list
:
/^start:/
:normal! jzt
GG
GG
GG
GG
GGH:
:set listchars-=trail:<
GG
GG
GG
GG
GG:
:put =g:lines
:'[,']w! test.out
ENDTEST

start:
	aa	
  bb	  
   cccc	 
dd        ee  	
 

STARTTEST
:set listchars+=trail:<
:set nolist
:
/^start:/
:redir! >> test.out
:+1,$list
:redir END
:q!
ENDTEST

start:
  fff	  
	gg	
     h	
iii