From 17d2db93fd78eea9c957aea9bf7263b518abc6ad Mon Sep 17 00:00:00 2001
From: Christian Brabandt <cb@256bit.org>
Date: Mon, 13 Mar 2017 18:50:19 +0100
Subject: [PATCH] Check, that fg color can't be negative

---
 autoload/airline/highlighter.vim | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/autoload/airline/highlighter.vim b/autoload/airline/highlighter.vim
index af8e83d..16ae66e 100644
--- a/autoload/airline/highlighter.vim
+++ b/autoload/airline/highlighter.vim
@@ -95,7 +95,7 @@ function! s:CheckDefined(colors)
   if !exists("g:airline#highlighter#normal_fg_hi")
     let g:airline#highlighter#normal_fg_hi = synIDattr(synIDtrans(hlID('Normal')), 'fg', 'cterm')
   endif
-  if empty(g:airline#highlighter#normal_fg_hi)
+  if empty(g:airline#highlighter#normal_fg_hi) || g:airline#highlighter#normal_fg_hi < 0
     return a:colors
   endif