module FormErrorsHelper

def error_span(attribute, options = {})
  options[:span_class] ||= 'help-block'
  options[:error_class] ||= 'has-error'
  if errors_on?(attribute)
    @template.content_tag( :div, :class => options[:error_class] )  do
      content_tag( :span, errors_for(attribute), :class => options[:span_class] )
    end
  end
end

def errors_for(attribute)
  object.errors[attribute].try(:join, ', ') || object.errors[attribute].try(:to_s)
end

def errors_on?(attribute)
  object.errors[attribute].present? if object.respond_to?(:errors)
end