add jellybeans theme using new highlight group methods

README.md

@@ -7,9 +7,9 @@ Lean & mean statusline for vim that's light as air.
 # Features
 
 *  tiny core (under 200 lines), written with extensibility in mind (specifically adhering to the [open/closed principle][h]).
-*  integrates with a variety of plugins: [vim-bufferline][f], [fugitive][d], [unite][i], [ctrlp][j], [minibufexpl][o], [gundo][p], [undotree][q], [nerdtree][r], [tagbar][s], [syntastic][e] and [lawrencium][u].
+*  integrates with a variety of plugins, including: [vim-bufferline][f], [fugitive][d], [unite][i], [ctrlp][j], [minibufexpl][o], [gundo][p], [undotree][q], [nerdtree][r], [tagbar][s], [syntastic][e] and [lawrencium][u].
 *  looks good with regular fonts and provides configuration points so you can use unicode or powerline symbols.
-*  optimized for speed; it loads in 1ms.
+*  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.
 *  trivial to write colorschemes; for a minimal theme you need to edit 9 lines of colors (please send pull requests).
 *  supports 7.2 as the minimum Vim version
@@ -77,7 +77,7 @@ Contributions and pull requests are welcome.  Please take note of the following
 
 *  adhere to the existing style as much as possible; notably, 2 space indents and long-form keywords.
 *  keep the history clean! squash your branches before you submit a pull request. `pull --rebase` is your friend.
-*  this plugin got a lot more popular than i initially expected, if you make changes to the core, please test on as many versions of vim as possible.
+*  any changes to the core should be tested against Vim 7.2.
 *  if you submit a theme, please create a screenshot so it can be added to the [Wiki][n].
 
 # License

autoload/airline/themes.vim

@@ -13,3 +13,25 @@ function! airline#themes#generate_color_map(section1, section2, section3, file)
       \ 'file':           [ a:file[0]     , a:file[1]     , a:file[2]     , a:file[3]     , get(a:file    , 4, ''    ) ] ,
       \ }
 endfunction
+
+function! s:get_syn(group, what)
+  return synIDattr(synIDtrans(hlID(a:group)), a:what)
+endfunction
+
+function! s:get_array(fg, bg, opts)
+  return has('gui_running')
+        \ ? [ a:fg, a:bg, '', '', join(a:opts, ',') ]
+        \ : [ '', '', a:fg >= 0 ? a:fg : '', a:bg >= 0 ? a:bg : '', join(a:opts, ',') ]
+endfunction
+
+function! airline#themes#get_highlight(group, ...)
+  let fg = s:get_syn(a:group, 'fg')
+  let bg = s:get_syn(a:group, 'bg')
+  return s:get_array(fg, bg, a:000)
+endfunction
+
+function! airline#themes#get_highlight2(fg, bg, ...)
+  let fg = s:get_syn(a:fg[0], a:fg[1])
+  let bg = s:get_syn(a:bg[0], a:bg[1])
+  return s:get_array(fg, bg, a:000)
+endfunction

autoload/airline/themes/jellybeans.vim

@@ -0,0 +1,33 @@
+" This theme is an example of how to use helper functions to extract highlight
+" values from the corresponding colorscheme. It was written in a hurry, so it
+" is very minimalistic. If you are a jellybeans user and want to make updates,
+" please send pull requests.
+
+" Here are examples where the entire highlight group is copied and an airline
+" compatible color array is generated.
+let s:file = airline#themes#get_highlight('Constant')
+let s:N1 = airline#themes#get_highlight('DbgCurrent', 'bold')
+let s:N2 = airline#themes#get_highlight('Folded')
+let s:N3 = airline#themes#get_highlight('NonText')
+let g:airline#themes#jellybeans#normal = airline#themes#generate_color_map(s:N1, s:N2, s:N3, s:file)
+
+let s:I1 = airline#themes#get_highlight('DiffAdd', 'bold')
+let s:I2 = s:N2
+let s:I3 = s:N3
+let g:airline#themes#jellybeans#insert = airline#themes#generate_color_map(s:I1, s:I2, s:I3, s:file)
+
+let s:R1 = airline#themes#get_highlight('WildMenu', 'bold')
+let s:R2 = s:N2
+let s:R3 = s:N3
+let g:airline#themes#jellybeans#replace = airline#themes#generate_color_map(s:R1, s:R2, s:R3, s:file)
+
+" Sometimes you want to mix and match colors from different groups, you can do
+" that with this method.
+let s:V1 = airline#themes#get_highlight2(['TabLineSel', 'bg'], ['DiffDelete', 'bg'], 'bold')
+let s:V2 = s:N2
+let s:V3 = s:N3
+let g:airline#themes#jellybeans#visual = airline#themes#generate_color_map(s:V1, s:V2, s:V3, s:file)
+
+" And of course, you can always do it manually as well.
+let s:IA = [ '#444444', '#1c1c1c', 237, 234 ]
+let g:airline#themes#jellybeans#inactive = airline#themes#generate_color_map(s:IA, s:IA, s:IA, s:file)

doc/airline.txt

@@ -205,9 +205,13 @@ statusline modified.  Here is an example:
 WRITING THEMES                                              *airline-themes*
 
 Themes are written "close to the metal" -- you will need to know some basic
-VimL syntax to write a theme, but if you're written in any programming
-language it will be easy to pick up.  Have a look at the dark.vim theme
-where it is fully documented.
+VimL syntax to write a theme, but if you've written in any programming
+language before it will be easy to pick up.
+
+The |dark.vim| theme fully documents this procedure and will guide you through
+the process.  The |jellybeans.vim| theme is another example of how to write a
+theme, but instead of manually declaring colors, it extracts the values from
+highlight groups.
 
 ==============================================================================
 TROUBLESHOOTING                                    *airline-troubleshooting*