Add vim-grepper extension

- Displays a segment when a grepper search is running

autoload/airline/extensions.vim

@@ -309,6 +309,11 @@ function! airline#extensions#load()
     call add(loaded_ext, 'gutentags')
   endif
 
+  if (get(g:, 'airline#extensions#grepper#enabled', 1) && get(g:, 'loaded_grepper', 0))
+    call airline#extensions#grepper#init(s:ext)
+    call add(loaded_ext, 'grepper')
+  endif
+
   if (get(g:, 'airline#extensions#xkblayout#enabled', 1) && exists('g:XkbSwitchLib'))
     call airline#extensions#xkblayout#init(s:ext)
     call add(loaded_ext, 'xkblayout')

autoload/airline/extensions/grepper.vim

@@ -0,0 +1,19 @@
+" MIT License. Copyright (c) 2014-2018 Mathias Andersson et al.
+" vim: et ts=2 sts=2 sw=2
+
+" Heavily derived from the Gutentags extension
+
+scriptencoding utf-8
+
+if !get(g:, 'loaded_grepper', 0)
+  finish
+endif
+
+function! airline#extensions#grepper#status()
+  let msg = grepper#statusline()
+  return empty(msg) ? '' : 'grepper'
+endfunction
+
+function! airline#extensions#grepper#init(ext)
+  call airline#parts#define_function('grepper', 'airline#extensions#grepper#status')
+endfunction

autoload/airline/init.vim

@@ -151,6 +151,7 @@ function! airline#init#bootstrap()
         \ 'neomake_warning_count', 'ale_error_count', 'ale_warning_count'])
   call airline#parts#define_text('capslock', '')
   call airline#parts#define_text('gutentags', '')
+  call airline#parts#define_text('grepper', '')
   call airline#parts#define_text('xkblayout', '')
   call airline#parts#define_text('keymap', '')
 
@@ -180,7 +181,7 @@ function! airline#init#sections()
     let g:airline_section_gutter = airline#section#create(['%='])
   endif
   if !exists('g:airline_section_x')
-    let g:airline_section_x = airline#section#create_right(['tagbar', 'gutentags', 'filetype'])
+    let g:airline_section_x = airline#section#create_right(['tagbar', 'gutentags', 'grepper', 'filetype'])
   endif
   if !exists('g:airline_section_y')
     let g:airline_section_y = airline#section#create_right(['ffenc'])

doc/airline.txt

@@ -1002,6 +1002,12 @@ vim-gutentags <https://github.com/ludovicchabant/vim-gutentags>
 * enable/disable vim-gutentags integration >
   let g:airline#extensions#gutentags#enabled = 1
 
+-------------------------------------                     *airline-grepper*
+vim-grepper <https://github.com/mhinz/vim-grepper>
+
+* enable/disable vim-grepper integration >
+  let g:airline#extensions#grepper#enabled = 1
+
 -------------------------------------                     *airline-capslock*
 vim-capslock <https://github.com/tpope/vim-capslock>