1 files changed, 75 insertions, 0 deletions
diff --git a/railties/lib/rails/application/route_inspector.rb b/railties/lib/rails/application/route_inspector.rb
new file mode 100644
index 0000000000..26652a8e5e
--- /dev/null
+++ b/railties/lib/rails/application/route_inspector.rb
@@ -0,0 +1,75 @@
+module Rails
+  class Application
+    ##
+    # This class is just used for displaying route information when someone
+    # executes `rake routes`.  People should not use this class.
+    class RouteInspector # :nodoc:
+      def initialize
+        @engines = ActiveSupport::OrderedHash.new
+      end
+
+      def format all_routes, filter = nil
+        if filter
+          all_routes = all_routes.select{ |route| route.defaults[:controller] == filter }
+        end
+
+        routes = collect_routes(all_routes)
+
+        formatted_routes(routes) +
+          formatted_routes_for_engines
+      end
+
+      def collect_routes(routes)
+        routes = routes.collect do |route|
+          route_reqs = route.requirements
+
+          rack_app = route.app unless route.app.class.name.to_s =~ /^ActionDispatch::Routing/
+
+          controller = route_reqs[:controller] || ':controller'
+          action     = route_reqs[:action]     || ':action'
+
+          endpoint = rack_app ? rack_app.inspect : "#{controller}##{action}"
+          constraints = route_reqs.except(:controller, :action)
+
+          reqs = endpoint
+          reqs += " #{constraints.inspect}" unless constraints.empty?
+
+          verb = route.verb.source.gsub(/[$^]/, '')
+
+          collect_engine_routes(reqs, rack_app)
+
+          {:name => route.name.to_s, :verb => verb, :path => route.path.spec.to_s, :reqs => reqs }
+        end
+
+        # Skip the route if it's internal info route
+        routes.reject { |r| r[:path] =~ %r{/rails/info/properties|^/assets} }
+      end
+
+      def collect_engine_routes(name, rack_app)
+        return unless rack_app && rack_app.respond_to?(:routes)
+        return if @engines[name]
+
+        routes = rack_app.routes
+        if routes.is_a?(ActionDispatch::Routing::RouteSet)
+          @engines[name] = collect_routes(routes.routes)
+        end
+      end
+
+      def formatted_routes_for_engines
+        @engines.map do |name, routes|
+          ["\nRoutes for #{name}:"] + formatted_routes(routes)
+        end.flatten
+      end
+
+      def formatted_routes(routes)
+        name_width = routes.map{ |r| r[:name].length }.max
+        verb_width = routes.map{ |r| r[:verb].length }.max
+        path_width = routes.map{ |r| r[:path].length }.max
+
+        routes.map do |r|
+          "#{r[:name].rjust(name_width)} #{r[:verb].ljust(verb_width)} #{r[:path].ljust(path_width)} #{r[:reqs]}"
+        end
+      end
+    end
+  end
+end