From 2ac5f2d86b27f517d4e9aac09f1e6af16dc262b1 Mon Sep 17 00:00:00 2001
From: h_east <h.east.727@gmail.com>
Date: Thu, 28 Jun 2018 20:49:24 +0900
Subject: [PATCH] Respect git managed tags

---
 plug.vim | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/plug.vim b/plug.vim
index 52c6b2a..3d95317 100644
--- a/plug.vim
+++ b/plug.vim
@@ -600,13 +600,28 @@ function! s:update(force, names)
   call s:update_impl(1, a:force, a:names)
 endfunction
 
+function! s:is_exec_helptags(docdir)
+  execute 'lcd' a:docdir
+  let result = v:false
+  let exts = uniq(sort(map(s:glob(a:docdir, '*.{txt,??x}'), 'v:val[-3:]')))
+  for ext in exts
+    let tagname = 'tags' . (ext == 'txt' ? '' : '-' . ext[:1])
+    if !filereadable(tagname) || empty(s:system('git ls-files ' . tagname))
+      let result = v:true
+      break
+    endif
+  endfor
+  lcd -
+  return result
+endfunc
+
 function! plug#helptags()
   if !exists('g:plugs')
     return s:err('plug#begin was not called')
   endif
   for spec in values(g:plugs)
     let docd = join([s:rtp(spec), 'doc'], '/')
-    if isdirectory(docd)
+    if isdirectory(docd) && s:is_exec_helptags(docd)
       silent! execute 'helptags' s:esc(docd)
     endif
   endfor