2 files changed, 48 insertions, 2 deletions
diff --git a/railties/lib/rails/info_controller.rb b/railties/lib/rails/info_controller.rb
index 49e5431a16..6e61cc3cb5 100644
--- a/railties/lib/rails/info_controller.rb
+++ b/railties/lib/rails/info_controller.rb
@@ -17,7 +17,28 @@ class Rails::InfoController < Rails::ApplicationController # :nodoc:
   end
 
   def routes
-    @routes_inspector = ActionDispatch::Routing::RoutesInspector.new(_routes.routes)
-    @page_title = 'Routes'
+    if path = params[:path]
+      path = URI.escape path
+      normalized_path = with_leading_slash path
+      render json: {
+        exact: match_route {|it| it.match normalized_path },
+        fuzzy: match_route {|it| it.spec.to_s.match path }
+      }
+    else
+      @routes_inspector = ActionDispatch::Routing::RoutesInspector.new(_routes.routes)
+      @page_title = 'Routes'
+    end
+  end
+
+  private
+
+  def match_route
+    _routes.routes.select {|route|
+      yield route.path
+    }.map {|route| route.path.spec.to_s }
+  end
+
+  def with_leading_slash(path)
+    ('/' + path).squeeze('/')
   end
 end
diff --git a/railties/test/rails_info_controller_test.rb b/railties/test/rails_info_controller_test.rb
index 25b0e761cb..d87b51d852 100644
--- a/railties/test/rails_info_controller_test.rb
+++ b/railties/test/rails_info_controller_test.rb
@@ -53,4 +53,29 @@ class InfoControllerTest < ActionController::TestCase
     assert_response :success
   end
 
+  test "info controller returns exact matches" do
+    exact_count = -> { JSON(response.body)['exact'].size }
+
+    get :routes, path: 'rails/info/route'
+    assert exact_count.call == 0, 'should not match incomplete routes'
+
+    get :routes, path: 'rails/info/routes'
+    assert exact_count.call == 1, 'should match complete routes'
+    
+    get :routes, path: 'rails/info/routes.html'
+    assert exact_count.call == 1, 'should match complete routes with optional parts'
+  end
+
+  test "info controller returns fuzzy matches" do
+    fuzzy_count = -> { JSON(response.body)['fuzzy'].size }
+
+    get :routes, path: 'rails/info'
+    assert fuzzy_count.call == 2, 'should match incomplete routes'
+
+    get :routes, path: 'rails/info/routes'
+    assert fuzzy_count.call == 1, 'should match complete routes'
+    
+    get :routes, path: 'rails/info/routes.html'
+    assert fuzzy_count.call == 0, 'should match optional parts of route literally'
+  end
 end