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

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