Make accommodations for component-local config

boardfish · boardfish · commit 3ef2840edfce · 2025-01-27T17:59:11.000Z
Introduces a `ViewComponent::GlobalConfig` object that will be the source for global configuration going forward. Ideally in the future, this will only house options that universally affect ViewComponent regardless of whether components are sourced from an engine or not (e.g. enabling the capture compatibility patch), and more options can move to a component-local config. For these options, classes inheriting from `ViewComponent::Base` will want to override configuration themselves.

This was initially written to support extracting the incoming strict_helpers_enabled? option, but applies to everything.
diff --git a/Rakefile b/Rakefile
@@ -95,7 +95,7 @@ namespace :docs do
     require "rails"
     require "action_controller"
     require "view_component"
-    ViewComponent::Base.config.view_component_path = "view_component"
+    ViewComponent::GlobalConfig.view_component_path = "view_component"
     require "view_component/docs_builder_component"
 
     error_keys = registry.keys.select { |key| key.to_s.include?("Error::MESSAGE") }.map(&:to_s)
diff --git a/app/controllers/concerns/view_component/preview_actions.rb b/app/controllers/concerns/view_component/preview_actions.rb
@@ -54,12 +54,12 @@ def previews
 
     # :doc:
     def default_preview_layout
-      ViewComponent::Base.config.default_preview_layout
+      GlobalConfig.default_preview_layout
     end
 
     # :doc:
     def show_previews?
-      ViewComponent::Base.config.show_previews
+      GlobalConfig.show_previews
     end
 
     # :doc:
@@ -102,7 +102,7 @@ def prepend_application_view_paths
     end
 
     def prepend_preview_examples_view_path
-      prepend_view_path(ViewComponent::Base.preview_paths)
+      prepend_view_path(GlobalConfig.preview_paths)
     end
   end
 end
diff --git a/app/helpers/preview_helper.rb b/app/helpers/preview_helper.rb
@@ -35,7 +35,7 @@ def find_template_data_for_preview_source(lookup_context:, template_identifier:)
       # Fetch template source via finding it through preview paths
       # to accomodate source view when exclusively using templates
       # for previews for Rails < 6.1.
-      all_template_paths = ViewComponent::Base.config.preview_paths.map do |preview_path|
+      all_template_paths = ViewComponent::GlobalConfig.preview_paths.map do |preview_path|
         Dir.glob("#{preview_path}/**/*")
       end.flatten
 
@@ -80,6 +80,6 @@ def prism_language_name_by_template_path(template_file_path:)
   # :nocov:
 
   def serve_static_preview_assets?
-    ViewComponent::Base.config.show_previews && Rails.application.config.public_file_server.enabled
+    ViewComponent::GlobalConfig.show_previews && Rails.application.config.public_file_server.enabled
   end
 end
diff --git a/app/views/view_components/preview.html.erb b/app/views/view_components/preview.html.erb
@@ -1,5 +1,5 @@
 <% if @render_args[:component] %>
-  <% if ViewComponent::Base.config.render_monkey_patch_enabled || Rails.version.to_f >= 6.1 %>
+  <% if ViewComponent::GlobalConfig.render_monkey_patch_enabled || Rails.version.to_f >= 6.1 %>
     <%= render(@render_args[:component], @render_args[:args], &@render_args[:block]) %>
   <% else %>
     <%= render_component(@render_args[:component], &@render_args[:block]) %>
@@ -8,6 +8,6 @@
   <%= render template: @render_args[:template], locals: @render_args[:locals] || {} %>
 <% end %>
 
-<% if ViewComponent::Base.config.show_previews_source %>
+<% if ViewComponent::GlobalConfig.show_previews_source %>
   <%= preview_source %>
 <% end %>
diff --git a/docs/CHANGELOG.md b/docs/CHANGELOG.md
@@ -10,6 +10,10 @@ nav_order: 5
 
 ## main
 
+* Make accommodations for component-local config to be introduced in future.
+
+    *Simon Fish*
+
 * Remove JS and CSS docs as they proved difficult to maintain and lacked consensus.
 
     *Joel Hawksley*
@@ -1410,7 +1414,7 @@ Run into an issue with this release? [Let us know](https://github.com/ViewCompon
 
     *Joel Hawksley*
 
-* The ViewComponent team at GitHub is hiring! We're looking for a Rails engineer with accessibility experience: [https://boards.greenhouse.io/github/jobs/4020166](https://boards.greenhouse.io/github/jobs/4020166). Reach out to joelhawksley@github.com with any questions!
+* The ViewComponent team at GitHub is hiring! We're looking for a Rails engineer with accessibility experience: [https://boards.greenhouse.io/github/jobs/4020166](https://boards.greenhouse.io/github/jobs/4020166). Reach out to <joelhawksley@github.com> with any questions!
 
 * The ViewComponent team is hosting a happy hour at RailsConf. Join us for snacks, drinks, and stickers: [https://www.eventbrite.com/e/viewcomponent-happy-hour-tickets-304168585427](https://www.eventbrite.com/e/viewcomponent-happy-hour-tickets-304168585427)
 
@@ -2174,7 +2178,7 @@ Run into an issue with this release? [Let us know](https://github.com/ViewCompon
 
     *Matheus Richard*
 
-* Are you interested in building the future of ViewComponent? GitHub is looking to hire a Senior Engineer to work on Primer ViewComponents and ViewComponent. Apply here: [US/Canada](https://github.com/careers) / [Europe](https://boards.greenhouse.io/github/jobs/3132294). Feel free to reach out to joelhawksley@github.com with any questions.
+* Are you interested in building the future of ViewComponent? GitHub is looking to hire a Senior Engineer to work on Primer ViewComponents and ViewComponent. Apply here: [US/Canada](https://github.com/careers) / [Europe](https://boards.greenhouse.io/github/jobs/3132294). Feel free to reach out to <joelhawksley@github.com> with any questions.
 
     *Joel Hawksley*
 
@@ -2192,7 +2196,7 @@ Run into an issue with this release? [Let us know](https://github.com/ViewCompon
 
 ## 2.31.0
 
-_Note: This release includes an underlying change to Slots that may affect incorrect usage of the API, where Slots were set on a line prefixed by `<%=`. The result of setting a Slot shouldn't be returned. (`<%`)_
+*Note: This release includes an underlying change to Slots that may affect incorrect usage of the API, where Slots were set on a line prefixed by `<%=`. The result of setting a Slot shouldn't be returned. (`<%`)*
 
 * Add `#with_content` to allow setting content without a block.
 
@@ -2640,7 +2644,7 @@ _Note: This release includes an underlying change to Slots that may affect incor
 
   * The gem name is now `view_component`.
   * ViewComponent previews are now accessed at `/rails/view_components`.
-  * ViewComponents can _only_ be rendered with the instance syntax: `render(MyComponent.new)`. Support for all other syntaxes has been removed.
+  * ViewComponents can *only* be rendered with the instance syntax: `render(MyComponent.new)`. Support for all other syntaxes has been removed.
   * ActiveModel::Validations have been removed. ViewComponent generators no longer include validations.
   * In Rails 6.1, no monkey patching is used.
   * `to_component_class` has been removed.
diff --git a/lib/rails/generators/abstract_generator.rb b/lib/rails/generators/abstract_generator.rb
@@ -29,7 +29,7 @@ def file_name
     end
 
     def component_path
-      ViewComponent::Base.config.view_component_path
+      GlobalConfig.view_component_path
     end
 
     def stimulus_controller
@@ -42,15 +42,15 @@ def stimulus_controller
     end
 
     def sidecar?
-      options["sidecar"] || ViewComponent::Base.config.generate.sidecar
+      options["sidecar"] || GlobalConfig.generate.sidecar
     end
 
     def stimulus?
-      options["stimulus"] || ViewComponent::Base.config.generate.stimulus_controller
+      options["stimulus"] || GlobalConfig.generate.stimulus_controller
     end
 
     def typescript?
-      options["typescript"] || ViewComponent::Base.config.generate.typescript
+      options["typescript"] || GlobalConfig.generate.typescript
     end
   end
 end
diff --git a/lib/rails/generators/component/component_generator.rb b/lib/rails/generators/component/component_generator.rb
@@ -13,12 +13,12 @@ class ComponentGenerator < Rails::Generators::NamedBase
       check_class_collision suffix: "Component"
 
       class_option :inline, type: :boolean, default: false
-      class_option :locale, type: :boolean, default: ViewComponent::Base.config.generate.locale
+      class_option :locale, type: :boolean, default: ViewComponent::GlobalConfig.generate.locale
       class_option :parent, type: :string, desc: "The parent class for the generated component"
-      class_option :preview, type: :boolean, default: ViewComponent::Base.config.generate.preview
+      class_option :preview, type: :boolean, default: ViewComponent::GlobalConfig.generate.preview
       class_option :sidecar, type: :boolean, default: false
       class_option :stimulus, type: :boolean,
-        default: ViewComponent::Base.config.generate.stimulus_controller
+        default: ViewComponent::GlobalConfig.generate.stimulus_controller
       class_option :skip_suffix, type: :boolean, default: false
 
       def create_component_file
@@ -42,7 +42,7 @@ def create_component_file
       def parent_class
         return options[:parent] if options[:parent]
 
-        ViewComponent::Base.config.component_parent_class || default_parent_class
+        ViewComponent::GlobalConfig.component_parent_class || default_parent_class
       end
 
       def initialize_signature
diff --git a/lib/rails/generators/locale/component_generator.rb b/lib/rails/generators/locale/component_generator.rb
@@ -12,7 +12,7 @@ class ComponentGenerator < ::Rails::Generators::NamedBase
       class_option :sidecar, type: :boolean, default: false
 
       def create_locale_file
-        if ViewComponent::Base.config.generate.distinct_locale_files
+        if ViewComponent::GlobalConfig.generate.distinct_locale_files
           I18n.available_locales.each do |locale|
             create_file destination(locale), translations_hash([locale]).to_yaml
           end
diff --git a/lib/rails/generators/preview/component_generator.rb b/lib/rails/generators/preview/component_generator.rb
@@ -4,13 +4,13 @@ module Preview
   module Generators
     class ComponentGenerator < ::Rails::Generators::NamedBase
       source_root File.expand_path("templates", __dir__)
-      class_option :preview_path, type: :string, desc: "Path for previews, required when multiple preview paths are configured", default: ViewComponent::Base.config.generate.preview_path
+      class_option :preview_path, type: :string, desc: "Path for previews, required when multiple preview paths are configured", default: ViewComponent::GlobalConfig.generate.preview_path
 
       argument :attributes, type: :array, default: [], banner: "attribute"
       check_class_collision suffix: "ComponentPreview"
 
       def create_preview_file
-        preview_paths = ViewComponent::Base.config.preview_paths
+        preview_paths = ViewComponent::GlobalConfig.preview_paths
         optional_path = options[:preview_path]
         return if preview_paths.count > 1 && optional_path.blank?
 
diff --git a/lib/rails/generators/rspec/component_generator.rb b/lib/rails/generators/rspec/component_generator.rb
@@ -16,7 +16,7 @@ def create_test_file
       private
 
       def spec_component_path
-        return "spec/components" unless ViewComponent::Base.config.generate.use_component_path_for_rspec_tests
+        return "spec/components" unless ViewComponent::GlobalConfig.generate.use_component_path_for_rspec_tests
 
         configured_component_path = component_path
         if configured_component_path.start_with?("app#{File::SEPARATOR}")
diff --git a/lib/view_component.rb b/lib/view_component.rb
@@ -13,6 +13,7 @@ module ViewComponent
   autoload :ComponentError
   autoload :Config
   autoload :Deprecation
+  autoload :GlobalConfig
   autoload :InlineTemplate
   autoload :Instrumentation
   autoload :Preview
diff --git a/lib/view_component/base.rb b/lib/view_component/base.rb
@@ -1,7 +1,6 @@
 # frozen_string_literal: true
 
 require "action_view"
-require "active_support/configurable"
 require "view_component/collection"
 require "view_component/compile_cache"
 require "view_component/compiler"
@@ -25,7 +24,7 @@ class << self
       #
       # @return [ActiveSupport::OrderedOptions]
       def config
-        ViewComponent::Config.current
+        GlobalConfig
       end
     end
 
@@ -48,6 +47,8 @@ def config
     class_attribute :__vc_strip_trailing_whitespace, instance_accessor: false, instance_predicate: false
     self.__vc_strip_trailing_whitespace = false # class_attribute:default doesn't work until Rails 5.2
 
+    delegate :component_config, to: :class
+
     attr_accessor :__vc_original_view_context
 
     # Components render in their own view context. Helpers and other functionality
@@ -227,7 +228,6 @@ def controller
     # @return [ActionView::Base]
     def helpers
       raise HelpersCalledBeforeRenderError if view_context.nil?
-
       # Attempt to re-use the original view_context passed to the first
       # component rendered in the rendering pipeline. This prevents the
       # instantiation of a new view_context via `controller.view_context` which
@@ -550,7 +550,7 @@ def render_template_for(variant = nil, format = nil)
         # If Rails application is loaded, removes the first part of the path and the extension.
         if defined?(Rails) && Rails.application
           child.virtual_path = child.identifier.gsub(
-            /(.*#{Regexp.quote(ViewComponent::Base.config.view_component_path)})|(\.rb)/, ""
+            /(.*#{Regexp.quote(GlobalConfig.view_component_path)})|(\.rb)/, ""
           )
         end
 
diff --git a/lib/view_component/config.rb b/lib/view_component/config.rb
@@ -11,7 +11,7 @@ class << self
       alias_method :default, :new
 
       def defaults
-        ActiveSupport::OrderedOptions.new.merge!({
+        ActiveSupport::InheritableOptions.new({
           generate: default_generate_options,
           preview_controller: "ViewComponentsController",
           preview_route: "/rails/view_components",
diff --git a/lib/view_component/engine.rb b/lib/view_component/engine.rb
@@ -6,7 +6,7 @@
 
 module ViewComponent
   class Engine < Rails::Engine # :nodoc:
-    config.view_component = ViewComponent::Config.current
+    config.view_component = ViewComponent::Config.defaults
 
     if Rails.version.to_f < 8.0
       rake_tasks do
@@ -16,8 +16,8 @@ class Engine < Rails::Engine # :nodoc:
       initializer "view_component.stats_directories" do |app|
         require "rails/code_statistics"
 
-        if Rails.root.join(ViewComponent::Base.view_component_path).directory?
-          Rails::CodeStatistics.register_directory("ViewComponents", ViewComponent::Base.view_component_path)
+        if Rails.root.join(GlobalConfig.view_component_path).directory?
+          Rails::CodeStatistics.register_directory("ViewComponents", GlobalConfig.view_component_path)
         end
 
         if Rails.root.join("test/components").directory?
@@ -29,7 +29,7 @@ class Engine < Rails::Engine # :nodoc:
     initializer "view_component.set_configs" do |app|
       options = app.config.view_component
 
-      %i[generate preview_controller preview_route show_previews_source].each do |config_option|
+      %i[generate preview_controller preview_route].each do |config_option|
         options[config_option] ||= ViewComponent::Base.public_send(config_option)
       end
       options.instrumentation_enabled = false if options.instrumentation_enabled.nil?
diff --git a/lib/view_component/global_config.rb b/lib/view_component/global_config.rb
@@ -0,0 +1,3 @@
+module ViewComponent
+  GlobalConfig = (defined?(Rails) && Rails.application) ? Rails.application.config.view_component : Config.defaults # standard:disable Naming/ConstantName
+end
diff --git a/lib/view_component/instrumentation.rb b/lib/view_component/instrumentation.rb
@@ -23,7 +23,7 @@ def render_in(view_context, &block)
     private
 
     def notification_name
-      return "!render.view_component" if ViewComponent::Base.config.use_deprecated_instrumentation_name
+      return "!render.view_component" if GlobalConfig.use_deprecated_instrumentation_name
 
       "render.view_component"
     end
diff --git a/lib/view_component/preview.rb b/lib/view_component/preview.rb
@@ -109,7 +109,7 @@ def load_previews
       private
 
       def preview_paths
-        Base.preview_paths
+        ViewComponent::GlobalConfig.preview_paths
       end
     end
   end
diff --git a/lib/view_component/rails/tasks/view_component.rake b/lib/view_component/rails/tasks/view_component.rake
@@ -7,8 +7,8 @@ namespace :view_component do
     # :nocov:
     require "rails/code_statistics"
 
-    if Rails.root.join(ViewComponent::Base.view_component_path).directory?
-      ::STATS_DIRECTORIES << ["ViewComponents", ViewComponent::Base.view_component_path]
+    if Rails.root.join(ViewComponent::GlobalConfig.view_component_path).directory?
+      ::STATS_DIRECTORIES << ["ViewComponents", ViewComponent::GlobalConfig.view_component_path]
     end
 
     if Rails.root.join("test/components").directory?
diff --git a/lib/view_component/test_helpers.rb b/lib/view_component/test_helpers.rb
@@ -250,7 +250,7 @@ def with_request_url(full_path, host: nil, method: nil, format: ViewComponent::B
     #
     # @return [ActionController::Base]
     def vc_test_controller
-      @vc_test_controller ||= __vc_test_helpers_build_controller(Base.test_controller.constantize)
+      @vc_test_controller ||= __vc_test_helpers_build_controller(GlobalConfig.test_controller.constantize)
     end
 
     # Access the request used by `render_inline`:
diff --git a/lib/view_component/use_helpers.rb b/lib/view_component/use_helpers.rb
@@ -1,5 +1,7 @@
 # frozen_string_literal: true
 
+require "view_component/errors"
+
 module ViewComponent::UseHelpers
   extend ActiveSupport::Concern
 
@@ -13,7 +15,7 @@ def use_helper(helper_method, from: nil, prefix: false)
 
       class_eval(<<-RUBY, __FILE__, __LINE__ + 1)
         def #{helper_method_name}(*args, &block)
-          raise HelpersCalledBeforeRenderError if view_context.nil?
+          raise ::ViewComponent::HelpersCalledBeforeRenderError if view_context.nil?
 
           #{define_helper(helper_method: helper_method, source: from)}
         end
diff --git a/test/sandbox/test/integration_test.rb b/test/sandbox/test/integration_test.rb
@@ -579,7 +579,7 @@ def test_render_component_in_turbo_stream
       expected_response_body = <<~TURBOSTREAM
         <turbo-stream action="update" target="area1"><template><span>Hello, world!</span></template></turbo-stream>
       TURBOSTREAM
-      if ViewComponent::Base.config.capture_compatibility_patch_enabled
+      if ViewComponent::GlobalConfig.capture_compatibility_patch_enabled
         assert_equal expected_response_body, response.body
       else
         assert_not_equal expected_response_body, response.body
@@ -716,22 +716,26 @@ def test_cached_partial
     Rails.cache.clear
   end
 
-  def test_config_options_shared_between_base_and_engine
-    config_entrypoints = [Rails.application.config.view_component, ViewComponent::Base.config]
-    2.times do
-      config_entrypoints.first.yield_self do |config|
+  def test_globalconfig_is_proxy_for_rails_app_config
+    config_entrypoints = [
+      ["Rails application config", Rails.application.config.view_component],
+      ["Global config", ViewComponent::GlobalConfig],
+      ["ViewComponent::Base's config", ViewComponent::Base.config]
+    ]
+    config_entrypoints.permutation(2) do |(first_entrypoint_name, first_entrypoint), (second_entrypoint_name, second_entrypoint)|
+      first_entrypoint.yield_self do |config|
         {
           generate: config.generate.dup.tap { |c| c.sidecar = true },
           preview_controller: "SomeOtherController",
           preview_route: "/some/other/route",
           show_previews_source: true
         }.each do |option, value|
           with_config_option(option, value, config_entrypoint: config) do
-            assert_equal(config.public_send(option), config_entrypoints.second.public_send(option))
+            assert_equal(config.public_send(option), second_entrypoint.public_send(option),
+              "#{first_entrypoint_name} should be the same as #{second_entrypoint_name} for #{option.inspect}")
           end
         end
       end
-      config_entrypoints.rotate!
     end
   end
 
diff --git a/test/sandbox/test/rendering_test.rb b/test/sandbox/test/rendering_test.rb
@@ -16,8 +16,8 @@ def test_render_inline_allocations
     MyComponent.ensure_compiled
 
     allocations = (Rails.version.to_f >= 8.0) ?
-      {"3.5.0" => 117, "3.4.1" => 117, "3.3.7" => 129} :
-      {"3.3.7" => 120, "3.3.0" => 120, "3.2.6" => 118, "3.1.6" => 118, "3.0.7" => 127}
+      {"3.5.0" => 117, "3.4.1" => 117, "3.3.7" => 128} :
+      {"3.3.7" => 119, "3.3.0" => 119, "3.2.6" => 117, "3.1.6" => 117, "3.0.7" => 126}
 
     assert_allocations(**allocations) do
       render_inline(MyComponent.new)
diff --git a/test/test_engine/test_helper.rb b/test/test_engine/test_helper.rb
