syntastic: distinguis errors and warnings

Currently the syntastic results are simply dumped into the error
section, however syntastic does internally distinguish between error and
warning sections.

Therefore change the syntastic extension to dump errors into the error
section and warnings into the warning section.

closes #1480

autoload/airline/extensions/syntastic.vim

@@ -7,15 +7,38 @@ if !exists(':SyntasticCheck')
   finish
 endif
 
-function! airline#extensions#syntastic#get_warnings()
+let s:error_symbol = get(g:, 'airline#extensions#syntastic#error_symbol', 'E:')
-  let errors = SyntasticStatuslineFlag()
+let s:warning_symbol = get(g:, 'airline#extensions#syntastic#warning_symbol', 'W:')
-  if strlen(errors) > 0
+
-    return errors.(g:airline_symbols.space)
+function! airline#extensions#syntastic#get_warning()
+  return airline#extensions#syntastic#get('warning')
+endfunction
+
+function! airline#extensions#syntastic#get_error()
+  return airline#extensions#syntastic#get('error')
+endfunction
+
+function! airline#extensions#syntastic#get(type)
+  let _backup = get(g:, 'syntastic_stl_format', '')
+  let is_err = (a:type  is# 'error')
+  let res    = ''
+  if is_err
+    let g:syntastic_stl_format = '%E{%e}'
+  else
+    let g:syntastic_stl_format = '%W{%w}'
+  endif
+  let cnt = SyntasticStatuslineFlag()
+  if !empty(_backup)
+    let g:syntastic_stl_format = _backup
+  endif
+  if cnt == 0
+    return ''
+  else
+    return (is_err ? s:error_symbol : s:warning_symbol).cnt
   endif
-  return ''
 endfunction
 
 function! airline#extensions#syntastic#init(ext)
-  call airline#parts#define_function('syntastic', 'airline#extensions#syntastic#get_warnings')
+  call airline#parts#define_function('syntastic-warn', 'airline#extensions#syntastic#get_warning')
+  call airline#parts#define_function('syntastic-err', 'airline#extensions#syntastic#get_error')
 endfunction
-

autoload/airline/init.vim

@@ -142,9 +142,10 @@ function! airline#init#bootstrap()
         \ 'raw': '/%L%{g:airline_symbols.maxlinenr}',
         \ 'accent': 'bold'})
   call airline#parts#define_function('ffenc', 'airline#parts#ffenc')
-  call airline#parts#define_empty(['hunks', 'branch', 'obsession', 'tagbar', 'syntastic',
+  call airline#parts#define_empty(['hunks', 'branch', 'obsession', 'tagbar',
-        \ 'eclim', 'whitespace','windowswap', 'ycm_error_count', 'ycm_warning_count',
+        \ 'syntastic-warn', 'syntastic-err', 'eclim', 'whitespace','windowswap',
-        \ 'neomake_error_count', 'neomake_warning_count', 'ale_error_count', 'ale_warning_count'])
+        \ 'ycm_error_count', 'ycm_warning_count', 'neomake_error_count',
+        \ 'neomake_warning_count', 'ale_error_count', 'ale_warning_count'])
   call airline#parts#define_text('capslock', '')
   call airline#parts#define_text('xkblayout', '')
 
@@ -189,9 +190,9 @@ function! airline#init#sections()
     endif
   endif
   if !exists('g:airline_section_error')
-    let g:airline_section_error = airline#section#create(['ycm_error_count', 'syntastic', 'eclim', 'neomake_error_count', 'ale_error_count'])
+    let g:airline_section_error = airline#section#create(['ycm_error_count', 'syntastic-err', 'eclim', 'neomake_error_count', 'ale_error_count'])
   endif
   if !exists('g:airline_section_warning')
-    let g:airline_section_warning = airline#section#create(['ycm_warning_count',  'neomake_warning_count', 'ale_warning_count', 'whitespace'])
+    let g:airline_section_warning = airline#section#create(['ycm_warning_count',  'syntastic-warn', 'neomake_warning_count', 'ale_warning_count', 'whitespace'])
   endif
 endfunction