From cb613ca05d3d195d52cfb5ce32f44c1d9e196214 Mon Sep 17 00:00:00 2001
From: Daniel Hahler <git@thequod.de>
Date: Fri, 16 Aug 2019 18:02:28 +0200
Subject: [PATCH] Fix :Gdiffsplit with diffopt+=vertical

Only remove "vertical" from `&diffopt` after calling
`s:diff_modifier()`.

Regressed in c972b2a.
References https://github.com/tpope/vim-fugitive/pull/805#issuecomment-522057790.
---
 autoload/fugitive.vim | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/autoload/fugitive.vim b/autoload/fugitive.vim
index e2182d1..1a2a1f3 100644
--- a/autoload/fugitive.vim
+++ b/autoload/fugitive.vim
@@ -4416,10 +4416,6 @@ function! s:Diff(autodir, keepfocus, mods, ...) abort
     endif
   endif
   try
-    if &diffopt =~# 'vertical'
-      let diffopt = &diffopt
-      set diffopt-=vertical
-    endif
     if exists('parents') && len(parents) > 1
       let mods = (a:autodir ? s:diff_modifier(len(parents) + 1) : '') . s:Mods(mods, 'leftabove')
       let nr = bufnr('')
@@ -4482,6 +4478,10 @@ function! s:Diff(autodir, keepfocus, mods, ...) abort
       let mods = s:Mods(mods, 'leftabove')
     endif
     let mods = (a:autodir ? s:diff_modifier(2) : '') . mods
+    if &diffopt =~# 'vertical'
+      let diffopt = &diffopt
+      set diffopt-=vertical
+    endif
     execute mods 'diffsplit' s:fnameescape(spec)
     let &l:readonly = &l:readonly
     redraw