deprecate instead of replace

Author: Judahmeek

CHANGELOG.md

@@ -26,7 +26,7 @@ Please follow the recommendations outlined at [keepachangelog.com](http://keepac
 
 ### Removed (Breaking Changes)
 
-- Removed `defer_generated_component_packs` configuration option. You can use `generated_component_packs_loading_strategy` instead. [PR 1712](https://github.com/shakacode/react_on_rails/pull/1712) by [AbanoubGhadban](https://github.com/AbanoubGhadban).
+- Deprecated `defer_generated_component_packs` configuration option. You should use `generated_component_packs_loading_strategy` instead. [PR 1712](https://github.com/shakacode/react_on_rails/pull/1712) by [AbanoubGhadban](https://github.com/AbanoubGhadban).
 
 ### [15.0.0-alpha.2] - 2025-03-07
 

docs/release-notes/15.0.0.md

@@ -34,13 +34,13 @@ Major improvements to component and store hydration:
 
 ### Component Hydration Changes
 
-- The `defer_generated_component_packs` configuration has been removed. Use `generated_component_packs_loading_strategy` instead.
+- The `defer_generated_component_packs` configuration has been deprecated. Use `generated_component_packs_loading_strategy` instead.
 - The `generated_component_packs_loading_strategy` defaults to `:async` for Shakapacker ≥ 8.2.0 and `:sync` for Shakapacker < 8.2.0.
 - The `force_load` configuration now defaults to `true`.
 - The new default values of `generated_component_packs_loading_strategy: :async` and `force_load: true` work together to optimize component hydration. Components now hydrate as soon as their code and server-rendered HTML are available, without waiting for the full page to load. This parallel processing significantly improves time-to-interactive by eliminating the traditional waterfall of waiting for page load before beginning hydration (It's critical for streamed HTML).
 
   - The previous need for deferring scripts to prevent race conditions has been eliminated due to improved hydration handling. Making scripts not defer is critical to execute the hydration scripts early before the page is fully loaded.
-  - The `force_load` configuration make `react-on-rails` hydrate components immediately as soon as their server-rendered HTML reaches the client, without waiting for the full page load.
+  - The `force_load` configuration makes `react-on-rails` hydrate components immediately as soon as their server-rendered HTML reaches the client, without waiting for the full page load.
   - If you want to keep the previous behavior, you can set `generated_component_packs_loading_strategy: :defer` or `force_load: false` in your `config/initializers/react_on_rails.rb` file.
   - If we want to keep the original behavior of `force_load` for only one or more components, you can set `force_load: false` in the `react_component` helper or `force_load` configuration.
   - Redux store support `force_load` option now and it uses `config.force_load` value as the default value. Which means that the redux store will hydrate immediately as soon as its server-side data reaches the client. You can override this behavior for individual redux stores by setting `force_load: false` in the `redux_store` helper.

lib/react_on_rails/configuration.rb

@@ -43,6 +43,7 @@ def self.configuration
       i18n_output_format: nil,
       components_subdirectory: nil,
       make_generated_server_bundle_the_entrypoint: false,
+      defer_generated_component_packs: false,
       # forces the loading of React components
       force_load: true,
       # Maximum time in milliseconds to wait for client-side component registration after page load.
@@ -60,7 +61,7 @@ class Configuration
                   :generated_assets_dirs, :generated_assets_dir, :components_subdirectory,
                   :webpack_generated_files, :rendering_extension, :build_test_command,
                   :build_production_command, :i18n_dir, :i18n_yml_dir, :i18n_output_format,
-                  :i18n_yml_safe_load_options,
+                  :i18n_yml_safe_load_options, :defer_generated_component_packs,
                   :server_render_method, :random_dom_id, :auto_load_bundle,
                   :same_bundle_for_client_and_server, :rendering_props_extension,
                   :make_generated_server_bundle_the_entrypoint,
@@ -70,7 +71,7 @@ class Configuration
     # rubocop:disable Metrics/AbcSize
     def initialize(node_modules_location: nil, server_bundle_js_file: nil, prerender: nil,
                    replay_console: nil, make_generated_server_bundle_the_entrypoint: nil,
-                   trace: nil, development_mode: nil,
+                   trace: nil, development_mode: nil, defer_generated_component_packs: nil,
                    logging_on_server: nil, server_renderer_pool_size: nil,
                    server_renderer_timeout: nil, raise_on_prerender_error: true,
                    skip_display_none: nil, generated_assets_dirs: nil,
@@ -122,6 +123,7 @@ def initialize(node_modules_location: nil, server_bundle_js_file: nil, prerender
       self.components_subdirectory = components_subdirectory
       self.auto_load_bundle = auto_load_bundle
       self.make_generated_server_bundle_the_entrypoint = make_generated_server_bundle_the_entrypoint
+      self.defer_generated_component_packs = defer_generated_component_packs
       self.force_load = force_load
       self.generated_component_packs_loading_strategy = generated_component_packs_loading_strategy
     end
@@ -152,9 +154,16 @@ def check_component_registry_timeout
       raise ReactOnRails::Error, "component_registry_timeout must be a positive integer"
     end
 
+    # rubocop:disable Metrics/CyclomaticComplexity
     def validate_generated_component_packs_loading_strategy
+      # rubocop:enable Metrics/CyclomaticComplexity
       if PackerUtils.shakapacker_version_requirement_met?([8, 2, 0])
         self.generated_component_packs_loading_strategy ||= :async
+      elsif defer_generated_component_packs
+        generated_component_packs_loading_strategy ||= :defer
+        Rails.logger.warn "[DEPRECATION] ReactOnRails: Use config." \
+                          "generated_component_packs_loading_strategy = :defer rather than " \
+                          "defer_generated_component_packs"
       elsif generated_component_packs_loading_strategy.nil?
         msg = <<~MSG
           **WARNING** ReactOnRails: Your current version of #{ReactOnRails::PackerUtils.packer_type.upcase_first} \