 
       for file in @inputFiles
         unless fs.existsSync(file)
-          @error "autoprefixer: File #{ file } doesn't exists"
-          @endWork()
+          @workError "autoprefixer: File #{ file } doesn't exists"
           continue
 
         try
           css = fs.readFileSync(file).toString()
         catch error
-          @error "autoprefixer: #{ error.message }"
-          @endWork()
+          @workError "autoprefixer: #{ error.message }"
           continue
 
         @compileCSS(css, file)

    @waiting -= 1
    @doneCallback() if @waiting <= 0

  # Lazy loading for Autoprefixer instance
  compiler: ->
    @compilerCache ||= autoprefixer(@requirements)

          @outputInited = true
          fs.writeFileSync(@outputFile, '')
        fs.appendFileSync(@outputFile, prefixed)
        @endWork()

      catch error
        @workError "autoprefixer: #{ error.message }"

    else if file
      fs.writeFile file, prefixed, (error) =>
