Add optional statusline indicator

doc/fugitive.txt

@@ -195,6 +195,15 @@ HEAD^:Makefile  The file named Makefile in the parent of HEAD
 :3              The current file in the merged branch during a conflict
 :/foo           The most recent commit with "foo" in the message
 
+STATUSLINE                                      *fugitive-statusline*
+
+                                                *fugitive#statusline()*
+Add %{fugitive#statusline()} to your statusline to get an indicator including
+the current branch and the currently edited file's commit.  If you don't have
+a statusline, this one matches the default when 'ruler' is set:
+>
+    set statusline=%<%f\ %h%m%r%{fugitive#statusline()}%=%-14.(%l,%c%V%)\ %P
+<
 ABOUT                                           *fugitive-about*
 
 Grab the latest version or report a bug on Github:

plugin/fugitive.vim

@@ -1608,6 +1608,32 @@ function! s:GF(mode) abort
   endtry
 endfunction
 
+" }}}1
+" Statusline {{{1
+
+function! s:repo_head_ref() dict abort
+  return readfile(s:repo().dir('HEAD'))[0]
+endfunction
+
+call s:add_methods('repo',['head_ref'])
+
+function! fugitive#statusline(...)
+  if !exists('b:git_dir')
+    return ''
+  endif
+  let status = 'Git'
+  if s:buffer().commit() != ''
+    let status .= ':' . s:buffer().commit()[0:7]
+  endif
+  let head = s:repo().head_ref()
+  if head =~# '^ref: '
+    let status .= s:sub(head,'^ref: %(refs/%(heads/|remotes/|tags/)=)=','(').')'
+  elseif head =~# '^\x\{40\}$'
+    let status .= '('.head[0:7].')'
+  endif
+  return '['.status.']'
+endfunction
+
 " }}}1
 
 " vim:set ft=vim ts=8 sw=2 sts=2: