Add suppress_unused_component_warnings config option

Add ability to suppress console.warn messages about registered components
that are not used on a page. This is useful in production environments
where many React components are registered globally but only a subset
are used on each page.

Configuration:
  config.suppress_unused_component_warnings = true

Changes:
- Add suppress_unused_component_warnings config option (default: false)
- Pass option to railsContext as suppressUnusedComponentWarnings
- Update CallbackRegistry to check the option before logging warnings
- Update TypeScript types and RBS signatures
- Update documentation and tests

Closes #2117

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: justin808

CHANGELOG.md

@@ -25,6 +25,8 @@ Changes since the last non-beta release.
 
 #### Added
 
+- **Suppress Unused Component Warnings**: Added `suppress_unused_component_warnings` configuration option to disable console warnings about registered components that are not used on a page. This is useful for production environments where many components are registered globally but only a subset are used on each page. Set `config.suppress_unused_component_warnings = true` in your React on Rails initializer. Note: This only affects React on Rails Pro users. [PR 2125](https://github.com/shakacode/react_on_rails/pull/2125) by [justin808](https://github.com/justin808).
+
 - **Service Dependency Checking for bin/dev**: Added optional `.dev-services.yml` configuration to validate required external services (Redis, PostgreSQL, Elasticsearch, etc.) are running before `bin/dev` starts the development server. Provides clear error messages with start commands and install hints when services are missing. Zero impact if not configured - backwards compatible with all existing installations. [PR 2098](https://github.com/shakacode/react_on_rails/pull/2098) by [justin808](https://github.com/justin808).
 
 #### Changed

docs/api-reference/configuration.md

@@ -710,6 +710,21 @@ config.component_registry_timeout = 5000  # default (5 seconds)
 
 Set to `0` to wait indefinitely (not recommended for production).
 
+#### suppress_unused_component_warnings
+
+**Type:** Boolean
+**Default:** `false`
+
+Suppress console warnings about registered components that are not used on a page:
+
+```ruby
+config.suppress_unused_component_warnings = true
+```
+
+When many React components are registered globally but only a subset are used on each page, React on Rails Pro will emit console warnings suggesting the unused components may be cleaned up. Set this option to `true` to suppress these warnings, which is useful in production environments where such warnings can be noisy.
+
+> **Note:** This configuration option only affects React on Rails Pro users, as the warnings are generated by the Pro package's component registry timeout feature.
+
 ### I18n Configuration
 
 These options are for applications using [react-intl](https://formatjs.io/docs/react-intl/) or similar internationalization libraries. If your application doesn't need i18n, you can skip this section.

packages/react-on-rails-pro/src/CallbackRegistry.ts

@@ -53,11 +53,16 @@ export default class CallbackRegistry<T> {
       this.waitingPromises.forEach((waitingPromiseInfo, itemName) => {
         waitingPromiseInfo.reject(this.createNotFoundError(itemName));
       });
-      this.notUsedItems.forEach((itemName) => {
-        console.warn(
-          `Warning: ${this.registryType} '${itemName}' was registered but never used. This may indicate unused code that can be removed.`,
-        );
-      });
+
+      // Only log warnings if not suppressed via configuration
+      const suppressWarnings = getRailsContext()?.suppressUnusedComponentWarnings;
+      if (!suppressWarnings) {
+        this.notUsedItems.forEach((itemName) => {
+          console.warn(
+            `Warning: ${this.registryType} '${itemName}' was registered but never used. This may indicate unused code that can be removed.`,
+          );
+        });
+      }
     };
 
     onPageLoaded(() => {

packages/react-on-rails/src/types/index.ts

@@ -20,6 +20,7 @@ type ReactComponent = ComponentType<any> | string;
 // Keep these in sync with method lib/react_on_rails/helper.rb#rails_context
 export type RailsContext = {
   componentRegistryTimeout: number;
+  suppressUnusedComponentWarnings: boolean;
   railsEnv: string;
   inMailer: boolean;
   i18nLocale: string;

packages/react-on-rails/tests/ClientRenderer.test.ts

@@ -59,6 +59,7 @@ describe('ClientRenderer', () => {
         httpAcceptLanguage: 'en',
         serverSide: false,
         componentRegistryTimeout: 0,
+        suppressUnusedComponentWarnings: false,
       });
       document.body.appendChild(railsContextElement);
 
@@ -116,6 +117,7 @@ describe('ClientRenderer', () => {
         httpAcceptLanguage: 'en',
         serverSide: false,
         componentRegistryTimeout: 0,
+        suppressUnusedComponentWarnings: false,
       });
       document.body.appendChild(railsContextElement);
 
@@ -145,6 +147,7 @@ describe('ClientRenderer', () => {
         httpAcceptLanguage: 'en',
         serverSide: false,
         componentRegistryTimeout: 0,
+        suppressUnusedComponentWarnings: false,
       });
       document.body.appendChild(railsContextElement);
 
@@ -195,6 +198,7 @@ describe('ClientRenderer', () => {
         httpAcceptLanguage: 'en',
         serverSide: false,
         componentRegistryTimeout: 0,
+        suppressUnusedComponentWarnings: false,
       });
       document.body.appendChild(railsContextElement);
 

react_on_rails/lib/react_on_rails/configuration.rb

@@ -64,6 +64,10 @@ def self.configuration
       # If exceeded, an error will be thrown for server-side rendered components not registered on the client.
       # Set to 0 to disable the timeout and wait indefinitely for component registration.
       component_registry_timeout: DEFAULT_COMPONENT_REGISTRY_TIMEOUT,
+      # Set to true to suppress warnings about registered components not being used on a page.
+      # This can be useful in production environments where many components are registered globally
+      # but only a subset are used on each page.
+      suppress_unused_component_warnings: false,
       generated_component_packs_loading_strategy: nil,
       server_bundle_output_path: DEFAULT_SERVER_BUNDLE_OUTPUT_PATH,
       enforce_private_server_bundles: false
@@ -82,7 +86,7 @@ class Configuration
                   :same_bundle_for_client_and_server, :rendering_props_extension,
                   :make_generated_server_bundle_the_entrypoint,
                   :generated_component_packs_loading_strategy,
-                  :component_registry_timeout,
+                  :component_registry_timeout, :suppress_unused_component_warnings,
                   :server_bundle_output_path, :enforce_private_server_bundles
 
     # Class instance variable and mutex to track if deprecation warning has been shown
@@ -144,7 +148,8 @@ def initialize(node_modules_location: nil, server_bundle_js_file: nil, prerender
                    i18n_dir: nil, i18n_yml_dir: nil, i18n_output_format: nil, i18n_yml_safe_load_options: nil,
                    random_dom_id: nil, server_render_method: nil, rendering_props_extension: nil,
                    components_subdirectory: nil, auto_load_bundle: nil,
-                   component_registry_timeout: nil, server_bundle_output_path: nil, enforce_private_server_bundles: nil)
+                   component_registry_timeout: nil, suppress_unused_component_warnings: nil,
+                   server_bundle_output_path: nil, enforce_private_server_bundles: nil)
       self.node_modules_location = node_modules_location.present? ? node_modules_location : Rails.root
       self.generated_assets_dirs = generated_assets_dirs
       self.generated_assets_dir = generated_assets_dir
@@ -169,6 +174,7 @@ def initialize(node_modules_location: nil, server_bundle_js_file: nil, prerender
       self.skip_display_none = skip_display_none
       self.rendering_props_extension = rendering_props_extension
       self.component_registry_timeout = component_registry_timeout
+      self.suppress_unused_component_warnings = suppress_unused_component_warnings || false
 
       # Server rendering:
       self.server_bundle_js_file = server_bundle_js_file

react_on_rails/lib/react_on_rails/helper.rb

@@ -274,6 +274,7 @@ def rails_context(server_side: true)
       @rails_context ||= begin
         result = {
           componentRegistryTimeout: ReactOnRails.configuration.component_registry_timeout,
+          suppressUnusedComponentWarnings: ReactOnRails.configuration.suppress_unused_component_warnings,
           railsEnv: Rails.env,
           inMailer: in_mailer?,
           # Locale settings

react_on_rails/sig/react_on_rails/configuration.rbs

@@ -32,6 +32,7 @@ module ReactOnRails
     attr_accessor generated_component_packs_loading_strategy: Symbol?
     attr_accessor immediate_hydration: bool
     attr_accessor component_registry_timeout: Integer
+    attr_accessor suppress_unused_component_warnings: bool
     attr_accessor server_bundle_output_path: String?
     attr_accessor enforce_private_server_bundles: bool
 
@@ -68,6 +69,7 @@ module ReactOnRails
       ?auto_load_bundle: bool?,
       ?immediate_hydration: bool?,
       ?component_registry_timeout: Integer?,
+      ?suppress_unused_component_warnings: bool?,
       ?server_bundle_output_path: String?,
       ?enforce_private_server_bundles: bool?
     ) -> void