Merge remote-tracking branch 'upstream/master'

bundle/vim-airline/autoload/airline/extensions/branch.vim

@@ -2,7 +2,6 @@
 " vim: et ts=2 sts=2 sw=2
 
 let s:has_fugitive = exists('*fugitive#head')
-let s:has_fugitive_detect = exists('*fugitive#detect')
 let s:has_lawrencium = exists('*lawrencium#statusline')
 let s:has_vcscommand = get(g:, 'airline#extensions#branch#use_vcscommand', 0) && exists('*VCSCommandGetStatusLine')
 
@@ -10,36 +9,77 @@ if !s:has_fugitive && !s:has_lawrencium && !s:has_vcscommand
   finish
 endif
 
+let s:git_dirs = {}
+function! s:get_git_branch(path)
+  if has_key(s:git_dirs, a:path)
+    return s:git_dirs[a:path]
+  endif
+
+  let dir = fugitive#extract_git_dir(a:path)
+  if empty(dir)
+    let name = ''
+  else
+    try
+      let line = join(readfile(dir . '/HEAD'))
+      if strpart(line, 0, 16) == 'ref: refs/heads/'
+        let name = strpart(line, 16)
+      else
+        " raw commit hash
+        let name = strpart(line, 0, 7)
+      endif
+    catch
+      let name = ''
+    endtry
+  endif
+
+  let s:git_dirs[a:path] = name
+  return name
+endfunction
+
 function! airline#extensions#branch#head()
-  let head = ''
+  if exists('b:airline_head') && !empty(b:airline_head)
+    return b:airline_head
+  endif
+
+  let b:airline_head = ''
+  let found_fugitive_head = 0
 
   if s:has_fugitive && !exists('b:mercurial_dir')
-    let head = fugitive#head()
+    let b:airline_head = fugitive#head(7)
+    let found_fugitive_head = 1
 
-    if empty(head) && s:has_fugitive_detect && !exists('b:git_dir')
-      call fugitive#detect(getcwd())
-      let head = fugitive#head()
+    if empty(b:airline_head) && !exists('b:git_dir')
+      let b:airline_head = s:get_git_branch(expand("%:p:h"))
     endif
   endif
 
-  if empty(head)
+  if empty(b:airline_head)
     if s:has_lawrencium
-      let head = lawrencium#statusline()
+      let b:airline_head = lawrencium#statusline()
     endif
   endif
 
-  if empty(head)
+  if empty(b:airline_head)
     if s:has_vcscommand
       call VCSCommandEnableBufferSetup()
       if exists('b:VCSCommandBufferInfo')
-        let head = get(b:VCSCommandBufferInfo, 0, '')
+        let b:airline_head = get(b:VCSCommandBufferInfo, 0, '')
       endif
     endif
   endif
 
-  return empty(head) || !s:check_in_path()
-        \ ? ''
-        \ : head
+  if empty(b:airline_head) || !found_fugitive_head && !s:check_in_path()
+    let b:airline_head = ''
+  endif
+
+  if exists("g:airline#extensions#branch#displayed_head_limit")
+    let w:displayed_head_limit = g:airline#extensions#branch#displayed_head_limit
+    if len(b:airline_head) > w:displayed_head_limit - 1
+      let b:airline_head = b:airline_head[0:w:displayed_head_limit - 1].'…'
+    endif
+  endif
+
+  return b:airline_head
 endfunction
 
 function! airline#extensions#branch#get_head()
@@ -78,5 +118,5 @@ function! airline#extensions#branch#init(ext)
   call airline#parts#define_function('branch', 'airline#extensions#branch#get_head')
 
   autocmd BufReadPost * unlet! b:airline_file_in_root
+  autocmd CursorHold,ShellCmdPost,CmdwinLeave * unlet! b:airline_head
 endfunction
-