New option: g:signify_realtime

By default Sy only updates signs when opening or writing a buffer that is backed
by a file on disk.

If that's too conservative to you, enable this option. It makes Sy update signs
on almost every occasion.

doc/signify.txt

@@ -47,7 +47,7 @@ Supported VCS:~
     accurev
     perforce
     tfs
-
+<
 ==============================================================================
 MODUS OPERANDI                                          *signify-modus-operandi*
 
@@ -117,9 +117,13 @@ OPTIONS                                                        *signify-options*
 Put these variables into your vimrc. The provided examples also indicate the
 default values, as long as no "Default:" section is given.
 
-All available options:~
+Most important options:~
 
     |g:signify_vcs_list|
+    |g:signify_realtime|
+
+Other options:~
+
     |g:signify_vcs_cmds|
     |g:signify_disable_by_default|
     |g:signify_skip_filetype|
@@ -177,6 +181,32 @@ NOTE: Some VCS rely on a an external diff tool to work properly (svn, darcs,
 bzr, fossil), thus you have to make sure that Vim can find a valid diff tool.
 So either the one you set through |g:signify_difftool| or "diff" by default.
 
+------------------------------------------------------------------------------
+                                                            *g:signify_realtime*  >
+    let g:signify_realtime = 0
+<
+By default, Sy only updates signs on:
+
+    |BufRead|       (opening a buffer)
+    |BufWritePost|  (saving a buffer)
+
+If that seems too conservative to you and you want more aggressive sign
+updates, enable this option.
+
+This will update signs on:
+
+    |BufEnter|      (opening or switching to another buffer)
+    |WinEnter|      (opening or switching to another window)
+    |BufWritePost|  (saving a buffer)
+    |CursorHold|    (cursor in normal mode wasn't moved for 'updatetime')
+    |CursorHoldI|   (cursor in insert mode wasn't moved for 'updatetime')
+    |FocusGained|   (when the OS window containing Vim got focus)
+
+NOTE: Running Sy on all these events would block too often for older Vim
+versions, thus this option requires Vim 7.4.1967+, which is the minimum
+version Sy needs for asynchronous execution. Older Vim versions silently
+ignore this option.
+
 ------------------------------------------------------------------------------
                                                             *g:signify_vcs_cmds*  >
     let g:signify_vcs_cmds = {

plugin/signify.vim

@@ -16,11 +16,16 @@ let g:signify_locked = 0
 augroup signify
   autocmd!
 
-  autocmd BufRead,BufWritePost * call sy#start()
-
   autocmd QuickFixCmdPre  *vimgrep* let g:signify_locked = 1
   autocmd QuickFixCmdPost *vimgrep* let g:signify_locked = 0
 
+  if get(g:, 'signify_realtime') && has('patch-7.4.1967')
+    autocmd BufEnter,BufWritePost,WinEnter * call sy#start()
+    autocmd CursorHold,CursorHoldI         * nested call s:save()
+    autocmd FocusGained                    * SignifyRefresh
+  else
+    autocmd BufRead,BufWritePost * call sy#start()
+
     if get(g:, 'signify_update_on_bufenter')
       autocmd BufEnter * nested call s:save()
     endif
@@ -30,10 +35,10 @@ augroup signify
     if get(g:, 'signify_cursorhold_insert')
       autocmd CursorHoldI * nested call s:save()
     endif
-
     if get(g:, 'signify_update_on_focusgained') && !has('gui_win32')
       autocmd FocusGained * SignifyRefresh
     endif
+  endif
 augroup END
 
 " Init: commands {{{1