Replace autoloader accessors with Rails.autoloaders.{main,once}

Rails.autoloader and Rails.once_autoloader was just tentative API good
enough for a first patch. Rails.autoloader is singular and does not
convey in its name that there is another autoloader. That might be
confusing, for example if you set a logger and miss traces. On the other
hand, the name `once_autoloader` is very close to being horrible.

Rails.autoloaders.main and Rails.autoloaders.once read better for my
taste, and have a nice symmetry. Also, both "main" and "once" are four
letters long, short and same length.

They are tagged as "rails.main" and "rails.once", respectively.

References #35235.

1 files changed, 4 insertions, 6 deletions

diff --git a/activesupport/lib/active_support/dependencies/zeitwerk_integration.rb b/activesupport/lib/active_support/dependencies/zeitwerk_integration.rb
index 75624bae09..55fc92ee8b 100644
--- a/activesupport/lib/active_support/dependencies/zeitwerk_integration.rb
+++ b/activesupport/lib/active_support/dependencies/zeitwerk_integration.rb
@@ -6,7 +6,7 @@ module ActiveSupport
       module Decorations
         def clear
           Dependencies.unload_interlock do
-            Rails.autoloader.reload
+            Rails.autoloaders.main.reload
           end
         end
 
@@ -19,9 +19,7 @@ module ActiveSupport
         end
 
         def autoloaded_constants
-          Rails.autoloaders.flat_map do |autoloader|
-            autoloader.loaded.to_a
-          end
+          (Rails.autoloaders.main.loaded + Rails.autoloaders.once.loaded).to_a
         end
 
         def autoloaded?(object)
@@ -46,9 +44,9 @@ module ActiveSupport
               next unless File.directory?(autoload_path)
 
               if autoload_once?(autoload_path)
-                Rails.once_autoloader.push_dir(autoload_path)
+                Rails.autoloaders.once.push_dir(autoload_path)
               else
-                Rails.autoloader.push_dir(autoload_path)
+                Rails.autoloaders.main.push_dir(autoload_path)
               end
             end