4 files changed, 40 insertions, 4 deletions
diff --git a/actionpack/CHANGELOG.md b/actionpack/CHANGELOG.md
index 35b9417b7d..dc627a4da4 100644
--- a/actionpack/CHANGELOG.md
+++ b/actionpack/CHANGELOG.md
@@ -1,3 +1,13 @@
+*   Show full route constraints in error message
+
+    When an optimized helper fails to generate, show the full route constraints
+    in the error message. Previously it would only show the contraints that were
+    required as part of the path.
+
+    Fixes #13592
+
+    *Andrew White*
+
 *   Use a custom route visitor for optimized url generation. Fixes #13349.
 
     *Andrew White*
diff --git a/actionpack/lib/action_dispatch/journey/formatter.rb b/actionpack/lib/action_dispatch/journey/formatter.rb
index 7764763791..4410c1b5d5 100644
--- a/actionpack/lib/action_dispatch/journey/formatter.rb
+++ b/actionpack/lib/action_dispatch/journey/formatter.rb
@@ -33,8 +33,8 @@ module ActionDispatch
           return [route.format(parameterized_parts), params]
         end
 
-        message = "No route matches #{constraints.inspect}"
-        message << " missing required keys: #{missing_keys.inspect}" if name
+        message = "No route matches #{Hash[constraints.sort].inspect}"
+        message << " missing required keys: #{missing_keys.sort.inspect}" if name
 
         raise ActionController::UrlGenerationError, message
       end
diff --git a/actionpack/lib/action_dispatch/routing/route_set.rb b/actionpack/lib/action_dispatch/routing/route_set.rb
index 1ea3bb17ce..10c8d748df 100644
--- a/actionpack/lib/action_dispatch/routing/route_set.rb
+++ b/actionpack/lib/action_dispatch/routing/route_set.rb
@@ -210,8 +210,9 @@ module ActionDispatch
             end
 
             def raise_generation_error(args, missing_keys)
-              message = "No route matches #{args.inspect}"
-              message << " missing required keys: #{missing_keys.inspect}"
+              constraints = Hash[@route.requirements.merge(args).sort]
+              message = "No route matches #{constraints.inspect}"
+              message << " missing required keys: #{missing_keys.sort.inspect}"
 
               raise ActionController::UrlGenerationError, message
             end
diff --git a/actionpack/test/dispatch/routing_test.rb b/actionpack/test/dispatch/routing_test.rb
index fad09d309a..d41b94511a 100644
--- a/actionpack/test/dispatch/routing_test.rb
+++ b/actionpack/test/dispatch/routing_test.rb
@@ -3708,3 +3708,28 @@ class TestRedirectRouteGeneration < ActionDispatch::IntegrationTest
     end
   end
 end
+
+class TestUrlGenerationErrors < ActionDispatch::IntegrationTest
+  Routes = ActionDispatch::Routing::RouteSet.new.tap do |app|
+    app.draw do
+      get "/products/:id" => 'products#show', :as => :product
+    end
+  end
+
+  def app; Routes end
+
+  include Routes.url_helpers
+
+  test "url helpers raise a helpful error message whem generation fails" do
+    url, missing = { action: 'show', controller: 'products', id: nil }, [:id]
+    message = "No route matches #{url.inspect} missing required keys: #{missing.inspect}"
+
+    # Optimized url helper
+    error = assert_raises(ActionController::UrlGenerationError){ product_path(nil) }
+    assert_equal message, error.message
+
+    # Non-optimized url helper
+    error = assert_raises(ActionController::UrlGenerationError, message){ product_path(id: nil) }
+    assert_equal message, error.message
+  end
+end