Properly register "custom" URL helpers as named helpers.

CustomUrlHelpers were introduced in ce7d5fb2e6, closing issue #22512.
They currently register themselves in an ivar that is never accessed.
This change removes the @custom_helpers special-case, and registers them
the way named routes are normally handled.

Without this, you can get route_defined?(:example_url) == false, while
still being able to call url_helpers.example_url and example_path.

Various popular gems such as 'rspec-rails' make use of route_defined?()
when determining how to proxy method calls or whether to define a route.

1 files changed, 6 insertions, 0 deletions

diff --git a/actionpack/test/dispatch/routing/custom_url_helpers_test.rb b/actionpack/test/dispatch/routing/custom_url_helpers_test.rb
index 338992dda5..cbbed66056 100644
--- a/actionpack/test/dispatch/routing/custom_url_helpers_test.rb
+++ b/actionpack/test/dispatch/routing/custom_url_helpers_test.rb
@@ -322,4 +322,10 @@ class TestCustomUrlHelpers < ActionDispatch::IntegrationTest
       end
     end
   end
+
+  def test_defining_direct_url_registers_helper_method
+    assert_equal "http://www.example.com/basket", Routes.url_helpers.symbol_url
+    assert_equal true, Routes.named_routes.route_defined?(:symbol_url), "'symbol_url' named helper not found"
+    assert_equal true, Routes.named_routes.route_defined?(:symbol_path), "'symbol_path' named helper not found"
+  end
 end