A simple Rails 3/4 integration test that spiders your application's links, checking that none return a 500 or 404

all_links_render_test.rb

require 'test_helper'

class AllLinksRenderTest < ActionDispatch::IntegrationTest

  test "all links render" do
    self.host = "example.com"
    spider "/"
  end

  def spider(path, spidered=[])
    STDERR.puts "Checking #{path}"
    spidered << path

    get path

    if redirect?
      if URI(response.location).host == self.host
        follow_redirect!
      else
        puts "Ignoring external redirect: #{path} -> #{response.location}"
        return
      end
    end

    # Assert page looks okay
    assert_response :success, "#{path} returned #{response.code} instead of 200\n\nResponse body:\n#{response.body}\n"
    
    # Add your own assertions (e.g. there is a signup link)

    # Spider all links
    css_select("a[href^='/']").each do |link|
      href = link.attributes['href'].gsub(/#.*$/,'') # strip frag-ids
      spider(href, spidered) unless spidered.include?(href)
    end
  end

end

so good.