From 591c4aa1eae35136708849a4fd9574ed37d7744e Mon Sep 17 00:00:00 2001
From: John Hawthorn <john@hawthorn.email>
Date: Tue, 7 Nov 2023 20:07:23 -0800
Subject: [PATCH] Eager load Journey Formatter cache

This cache is used when url_for is called without a named route (ie.
when it's called with hash options). Eager loading avoids building the
cache on the first call and potentially allows the memory to be shared
via CoW on forking servers.
---
 actionpack/lib/action_dispatch/journey/formatter.rb | 5 +++++
 actionpack/lib/action_dispatch/routing/route_set.rb | 1 +
 2 files changed, 6 insertions(+)

diff --git a/actionpack/lib/action_dispatch/journey/formatter.rb b/actionpack/lib/action_dispatch/journey/formatter.rb
index bccedd4f6c837..b27f482f6cdf5 100644
--- a/actionpack/lib/action_dispatch/journey/formatter.rb
+++ b/actionpack/lib/action_dispatch/journey/formatter.rb
@@ -104,6 +104,11 @@ def clear
         @cache = nil
       end
 
+      def eager_load!
+        cache
+        nil
+      end
+
       private
         def extract_parameterized_parts(route, options, recall)
           parameterized_parts = recall.merge(options)
diff --git a/actionpack/lib/action_dispatch/routing/route_set.rb b/actionpack/lib/action_dispatch/routing/route_set.rb
index 9d4adddb9e1eb..f5d665e7b72ee 100644
--- a/actionpack/lib/action_dispatch/routing/route_set.rb
+++ b/actionpack/lib/action_dispatch/routing/route_set.rb
@@ -386,6 +386,7 @@ def initialize(config = DEFAULT_CONFIG)
       def eager_load!
         router.eager_load!
         routes.each(&:eager_load!)
+        formatter.eager_load!
         nil
       end