fold exclude funcrefs into the default one.

autoload/airline.vim

@@ -73,11 +73,6 @@ function! airline#get_statusline(winnr, active)
 endfunction
 
 function! airline#update_statusline()
-  if airline#util#exec_funcrefs(g:airline_exclude_funcrefs)
-    call setwinvar(winnr(), '&statusline', '')
-    return
-  endif
-
   for nr in filter(range(1, winnr('$')), 'v:val != winnr()')
     call setwinvar(nr, 'airline_active', 0)
     call setwinvar(nr, '&statusline', airline#get_statusline(nr, 0))
@@ -90,9 +85,11 @@ function! airline#update_statusline()
   for section in s:sections
     unlet! w:airline_section_{section}
   endfor
-  call airline#util#exec_funcrefs(g:airline_statusline_funcrefs)
 
-  call setwinvar(winnr(), '&statusline', airline#get_statusline(winnr(), 1))
+  let err = airline#util#exec_funcrefs(g:airline_statusline_funcrefs)
+  if err == 0
+    call setwinvar(winnr(), '&statusline', airline#get_statusline(winnr(), 1))
+  endif
 endfunction
 
 function! airline#check_mode()

autoload/airline/extensions.vim

@@ -2,13 +2,9 @@
 " vim: et ts=2 sts=2 sw=2
 
 let s:ext = {}
-let s:ext._cursormove_funcrefs = []
 function! s:ext.add_statusline_funcref(funcref) dict
   call add(g:airline_statusline_funcrefs, a:funcref)
 endfunction
-function! s:ext.add_cursormove_funcref(funcref) dict
-  call add(self._cursormove_funcrefs, a:funcref)
-endfunction
 
 let s:script_path = expand('<sfile>:p:h')
 
@@ -35,6 +31,10 @@ endfunction
 
 let s:active_winnr = -1
 function! airline#extensions#update_statusline(...)
+  if s:is_excluded_window(a:000)
+    return -1
+  endif
+
   let s:active_winnr = winnr()
 
   if &buftype == 'quickfix'
@@ -67,7 +67,7 @@ function! airline#extensions#update_statusline(...)
   endfor
 endfunction
 
-function! airline#extensions#is_excluded_window(...)
+function! s:is_excluded_window(...)
   for matchft in g:airline_exclude_filetypes
     if matchft ==# &ft
       return 1
@@ -95,9 +95,6 @@ endfunction
 
 function! s:sync_active_winnr()
   if exists('#airline') && winnr() != s:active_winnr
-    if airline#util#exec_funcrefs(s:ext._cursormove_funcrefs)
-      return
-    endif
     call airline#update_statusline()
   endif
 endfunction
@@ -107,7 +104,6 @@ function! airline#extensions#load()
   autocmd CursorMoved * call <sid>sync_active_winnr()
 
   " load core funcrefs
-  call add(g:airline_exclude_funcrefs, function('airline#extensions#is_excluded_window'))
   call add(g:airline_statusline_funcrefs, function('airline#extensions#update_statusline'))
 
   if get(g:, 'loaded_unite', 0)

autoload/airline/extensions/ctrlp.vim

@@ -49,8 +49,9 @@ function! airline#extensions#ctrlp#ctrlp_airline_status(...)
   return len.dir
 endfunction
 
-function! airline#extensions#ctrlp#is_statusline_overwritten(...)
-  return match(&statusline, 'CtrlPlight') >= 0
+function! airline#extensions#ctrlp#apply(...)
+  " disable statusline overwrite if ctrlp already did it
+  return match(&statusline, 'CtrlPlight') >= 0 ? -1 : 0
 endfunction
 
 function! airline#extensions#ctrlp#init(ext)
@@ -58,6 +59,6 @@ function! airline#extensions#ctrlp#init(ext)
         \ 'main': 'airline#extensions#ctrlp#ctrlp_airline',
         \ 'prog': 'airline#extensions#ctrlp#ctrlp_airline_status',
         \ }
-  call a:ext.add_cursormove_funcref(function('airline#extensions#ctrlp#is_statusline_overwritten'))
+  call a:ext.add_statusline_funcref(function('airline#extensions#ctrlp#apply'))
 endfunction
 

doc/airline.txt

@@ -259,15 +259,15 @@ is an example of how you can extend vim-airline to support a new plugin.
   endfunction
   call add(g:airline_statusline_funcrefs, function('MyPlugin'))
 <
-                                                *g:airline_exclude_funcrefs*
-The g:airline_exclude_funcrefs variable is an array that's returns 1 or 0 to
-determine whether that particular window should be excluded from having its
-statusline modified.  Here is an example:
+
+You can also control what happens by returning an error code. Note that
+returning a value other than 0 will prevent any remaining extensions from
+having their funcrefs invoked.
 >
-  function! ExcludeFoo()
-    return &filetype == 'FooType'
+  function! MyPlugin(...)
+    return  0 " the default action, modify the statusline
+    return -1 " do not update the statusline
   endfunction
-  call add(g:airline_exclude_funcrefs, function('ExcludeFoo'))
 <
 
 ==============================================================================

plugin/airline.vim

@@ -25,7 +25,6 @@ call s:check_defined('g:airline_exclude_filenames', ['DebuggerWatch','DebuggerSt
 call s:check_defined('g:airline_exclude_filetypes', [])
 call s:check_defined('g:airline_exclude_preview', 0)
 call s:check_defined('g:airline_statusline_funcrefs', [])
-call s:check_defined('g:airline_exclude_funcrefs', [])
 
 call s:check_defined('g:airline_mode_map', {
       \ '__' : '------',
@@ -90,7 +89,7 @@ function! s:on_colorscheme_changed()
   call airline#load_theme()
 endfunction
 
-function airline#cmdwinenter()
+function airline#cmdwinenter(...)
   call airline#extensions#apply_left_override('Command Line', '')
 endfunction