class Middleman::CoreExtensions::ShowExceptions

def after_configuration
  app.use ::Rack::ShowExceptions if !app.build? && app.config[:show_exceptions]
end

def initialize(app, options_hash={}, &block)
  super
  return if app.config.defines_setting? :show_exceptions
  app.config.define_setting :show_exceptions, !!ENV['TEST'], 'Whether to catch and display exceptions'
end