vim-airline/autoload/airline/extensions/po.vim

" MIT License. Copyright (c) 2013-2016 Bailey Ling.
" vim: et ts=2 sts=2 sw=2

scriptencoding utf-8

function! airline#extensions#po#apply(...)
  if &ft ==# 'po'
    call airline#extensions#prepend_to_section('z', '%{airline#extensions#po#stats()}')
    autocmd airline BufWritePost * unlet! b:airline_po_stats
  endif
endfunction

function! airline#extensions#po#stats()
  if exists('b:airline_po_stats') && !empty(b:airline_po_stats)
    return b:airline_po_stats
  endif

  let airline_po_stats = system('msgfmt --statistics -o /dev/null -- '. expand('%:p'))
  if v:shell_error
    return ''
  endif
  try
    let b:airline_po_stats = '['. split(airline_po_stats, '\n')[0]. ']'
  catch
    let b:airline_po_stats = ''
  endtry
  if exists("g:airline#extensions#po#displayed_limit")
    let w:displayed_po_limit = g:airline#extensions#po#displayed_limit
    if len(b:airline_po_stats) > w:displayed_po_limit - 1
      let b:airline_po_stats = b:airline_po_stats[0:(w:displayed_po_limit - 1)].(&encoding==?'utf-8' ? '…' : '.')
    endif
  endif
  return b:airline_po_stats
endfunction

function! airline#extensions#po#init(ext)
    call a:ext.add_statusline_func('airline#extensions#po#apply')
endfunction