add gitgutter integration.

README.md

@@ -7,7 +7,7 @@ Lean & mean statusline for vim that's light as air.
 # Features
 
 *  tiny core written with extensibility in mind ([open/closed principle][8]).
-*  integrates with a variety of plugins, including: [vim-bufferline][6], [fugitive][4], [unite][9], [ctrlp][10], [minibufexpl][15], [gundo][16], [undotree][17], [nerdtree][18], [tagbar][19], [syntastic][5] and [lawrencium][21].
+*  integrates with a variety of plugins, including: [vim-bufferline][6], [fugitive][4], [unite][9], [ctrlp][10], [minibufexpl][15], [gundo][16], [undotree][17], [nerdtree][18], [tagbar][19], [vim-gitgutter][29], [syntastic][5] and [lawrencium][21].
 *  looks good with regular fonts and provides configuration points so you can use unicode or powerline symbols.
 *  optimized for speed; it loads in under a millisecond.
 *  fully customizable; if you know a little `statusline` syntax you can tweak it to your needs.
@@ -135,3 +135,4 @@ MIT license. Copyright (c) 2013 Bailey Ling.
 [26]: https://github.com/nanotech/jellybeans.vim
 [27]: https://github.com/bling/vim-airline/wiki/FAQ
 [28]: https://github.com/chrisbra/csv.vim
+[29]: https://github.com/airblade/vim-gitgutter

autoload/airline/extensions.vim

@@ -128,6 +128,10 @@ function! airline#extensions#load()
     call airline#extensions#undotree#init(s:ext)
   endif
 
+  if g:airline_enable_hunks && exists('*GitGutterGetHunks')
+    call airline#extensions#hunks#init(s:ext)
+  endif
+
   if g:airline_enable_tagbar && exists(':TagbarToggle')
     call airline#extensions#tagbar#init(s:ext)
   endif

autoload/airline/extensions/hunks.vim

@@ -0,0 +1,31 @@
+" MIT License. Copyright (c) 2013 Bailey Ling.
+" vim: et ts=2 sts=2 sw=2
+
+function! airline#extensions#hunks#get_hunks()
+  try
+    " throws an error when first entering a buffer, so we gotta swallow it
+    silent! let hunks = GitGutterGetHunks()
+    let added = 0
+    let removed = 0
+    let changed = 0
+    for hunk in hunks
+      let diff = hunk[3] - hunk[1]
+      if diff > 0
+        let added += diff
+      elseif diff < 0
+        let removed -= diff
+      else
+        let changed += 1
+      endif
+    endfor
+    return printf('+%s ~%s -%s', added, changed, removed)
+  catch
+    return ''
+  endtry
+  return ''
+endfunction
+
+function! airline#extensions#hunks#init(ext)
+  let g:airline_section_b .= '%{airline#extensions#hunks#get_hunks()} '
+endfunction
+

doc/airline.txt

@@ -199,13 +199,19 @@ tagbar <https://github.com/majutsushi/>
                                                                *airline-csv*
 csv.vim <https://github.com/chrisbra/csv.vim>
 
-* enable/disable csv integration for displaying the current column.
+* enable/disable csv integration for displaying the current column. >
   let g:airline_enable_csv = 1
->
+<
 * change how columns are displayed. >
   let g:airline#extensions#csv#column_display = 'Number' (default)
   let g:airline#extensions#csv#column_display = 'Name'
->
+<
+                                                             *airline-hunks*
+vim-gitgutter <https://github.com/airblade/vim-gitgutter>
+
+* enable/disable detecting changed hunks under source control. >
+  let g:airline_enable_hunks = 1
+<
 
 ==============================================================================
 FUNCREFS                                                  *airline-funcrefs*

plugin/airline.vim

@@ -21,6 +21,7 @@ call s:check_defined('g:airline_enable_branch', 1)
 call s:check_defined('g:airline_enable_syntastic', 1)
 call s:check_defined('g:airline_enable_tagbar', 1)
 call s:check_defined('g:airline_enable_csv', 1)
+call s:check_defined('g:airline_enable_hunks', 1)
 call s:check_defined('g:airline_detect_iminsert', 0)
 call s:check_defined('g:airline_detect_modified', 1)
 call s:check_defined('g:airline_detect_paste', 1)