Reproducing Rails issue #671 ~> https://github.com/rails/rails/issues/671

application_controller.rb

# app/controllers/application_controller.rb
# Rescue from RoutingError

class ApplicationController < ActionController::Base
  protect_from_forgery
  
  rescue_from ActionController::RoutingError, :with => :render_routing_error

  def render_routing_error
    render :text => "Rescued from routing error.", :status => 404
  end
end

development.rb

# config/environments.rb

# Commented line   #config.action_view.debug_rjs             = true
# Set config.consider_all_requests_local       = false

RoutingError::Application.configure do
  # Settings specified here will take precedence over those in config/application.rb

  # In the development environment your application's code is reloaded on
  # every request.  This slows down response time but is perfect for development
  # since you don't have to restart the webserver when you make code changes.
  config.cache_classes = false

  # Log error messages when you accidentally call methods on nil.
  config.whiny_nils = true

  # Show full error reports and disable caching
  config.consider_all_requests_local       = false
  #config.action_view.debug_rjs             = true
  config.action_controller.perform_caching = false

  # Don't care if the mailer can't send
  config.action_mailer.raise_delivery_errors = false

  # Print deprecation notices to the Rails logger
  config.active_support.deprecation = :log

  # Only use best-standards-support built into browsers
  config.action_dispatch.best_standards_support = :builtin
end