Merge pull request #35036 from rails/av-base-subclass

Move compiled ERB to an AV::Base subclass

actionpack/lib/action_dispatch/middleware/debug_view.rb

@@ -15,6 +15,10 @@ def initialize(assigns)
       super(renderer, assigns)
     end
 
+    def compiled_method_container
+      self.class
+    end
+
     def debug_params(params)
       clean_params = params.clone
       clean_params.delete("action")

actionview/CHANGELOG.md

+*   ActionView::Template.finalize_compiled_template_methods is deprecated with
+    no replacement.
+
+    *tenderlove*
+
+*   config.action_view.finalize_compiled_template_methods is deprecated with
+    no replacement.
+
+    *tenderlove*
+
 *   Ensure unique DOM IDs for collection inputs with float values.
     Fixes #34974
 

actionview/lib/action_view.rb

@@ -35,7 +35,6 @@ module ActionView
   eager_autoload do
     autoload :Base
     autoload :Context
-    autoload :CompiledTemplates, "action_view/context"
     autoload :Digestor
     autoload :Helpers
     autoload :LookupContext

actionview/lib/action_view/base.rb

@@ -11,10 +11,6 @@
 require "action_view/lookup_context"
 
 module ActionView #:nodoc:
-  module CompiledTemplates #:nodoc:
-    # holds compiled template code
-  end
-
   # = Action View Base
   #
   # Action View templates can be written in several ways.
@@ -146,8 +142,6 @@ module CompiledTemplates #:nodoc:
   class Base
     include Helpers, ::ERB::Util, Context
 
-    include CompiledTemplates
-
     # Specify the proc used to decorate input tags that refer to attributes with errors.
     cattr_accessor :field_error_proc, default: Proc.new { |html_tag, instance| "<div class=\"field_with_errors\">#{html_tag}</div>".html_safe }
 
@@ -186,6 +180,20 @@ def cache_template_loading=(value)
       def xss_safe? #:nodoc:
         true
       end
+
+      def with_empty_template_cache # :nodoc:
+        subclass = Class.new(self) {
+          # We can't implement these as self.class because subclasses will
+          # share the same template cache as superclasses, so "changed?" won't work
+          # correctly.
+          define_method(:compiled_method_container)           { subclass }
+          define_singleton_method(:compiled_method_container) { subclass }
+        }
+      end
+
+      def changed?(other) # :nodoc:
+        compiled_method_container != other.compiled_method_container
+      end
     end
 
     attr_reader :view_renderer
@@ -260,7 +268,11 @@ def run(method, locals, buffer, &block)
     end
 
     def compiled_method_container
-      CompiledTemplates
+      raise NotImplementedError, <<~msg
+        Subclasses of ActionView::Base must implement `compiled_method_container`
+        or use the class method `with_empty_template_cache` for constructing
+        an ActionView::Base subclass that has an empty cache.
+      msg
     end
 
     ActiveSupport.run_load_hooks(:action_view, self)

actionview/lib/action_view/lookup_context.rb

@@ -68,12 +68,17 @@ def self.get(details)
       end
 
       def self.clear
+        @view_context_class = nil
         @details_keys.clear
       end
 
       def self.digest_caches
         @details_keys.values
       end
+
+      def self.view_context_class(klass)
+        @view_context_class ||= klass.with_empty_template_cache
+      end
     end
 
     # Add caching behavior on top of Details.

actionview/lib/action_view/railtie.rb

@@ -6,11 +6,13 @@
 module ActionView
   # = Action View Railtie
   class Railtie < Rails::Engine # :nodoc:
+    NULL_OPTION = Object.new
+
     config.action_view = ActiveSupport::OrderedOptions.new
     config.action_view.embed_authenticity_token_in_remote_forms = nil
     config.action_view.debug_missing_translation = true
     config.action_view.default_enforce_utf8 = nil
-    config.action_view.finalize_compiled_template_methods = true
+    config.action_view.finalize_compiled_template_methods = NULL_OPTION
 
     config.eager_load_namespaces << ActionView
 
@@ -48,8 +50,11 @@ class Railtie < Rails::Engine # :nodoc:
 
     initializer "action_view.finalize_compiled_template_methods" do |app|
       ActiveSupport.on_load(:action_view) do
-        ActionView::Template.finalize_compiled_template_methods =
-          app.config.action_view.delete(:finalize_compiled_template_methods)
+        option = app.config.action_view.delete(:finalize_compiled_template_methods)
+
+        if option != NULL_OPTION
+          ActiveSupport::Deprecation.warn "action_view.finalize_compiled_template_methods is deprecated and has no effect"
+        end
       end
     end
 

actionview/lib/action_view/rendering.rb

@@ -35,24 +35,36 @@ def process(*) #:nodoc:
     end
 
     module ClassMethods
-      def view_context_class
-        @view_context_class ||= begin
-          supports_path = supports_path?
-          routes  = respond_to?(:_routes)  && _routes
-          helpers = respond_to?(:_helpers) && _helpers
-
-          Class.new(ActionView::Base) do
-            if routes
-              include routes.url_helpers(supports_path)
-              include routes.mounted_helpers
-            end
-
-            if helpers
-              include helpers
-            end
+      def _routes
+      end
+
+      def _helpers
+      end
+
+      def build_view_context_class(klass, supports_path, routes, helpers)
+        Class.new(klass) do
+          if routes
+            include routes.url_helpers(supports_path)
+            include routes.mounted_helpers
+          end
+
+          if helpers
+            include helpers
           end
         end
       end
+
+      def view_context_class
+        klass = ActionView::LookupContext::DetailsKey.view_context_class(ActionView::Base)
+
+        @view_context_class ||= build_view_context_class(klass, supports_path?, _routes, _helpers)
+
+        if klass.changed?(@view_context_class)
+          @view_context_class = build_view_context_class(klass, supports_path?, _routes, _helpers)
+        end
+
+        @view_context_class
+      end
     end
 
     def view_context_class

actionview/lib/action_view/template.rb

@@ -2,6 +2,7 @@
 
 require "active_support/core_ext/object/try"
 require "active_support/core_ext/kernel/singleton_class"
+require "active_support/deprecation"
 require "thread"
 require "delegate"
 
@@ -10,7 +11,13 @@ module ActionView
   class Template
     extend ActiveSupport::Autoload
 
-    mattr_accessor :finalize_compiled_template_methods, default: true
+    def self.finalize_compiled_template_methods
+      ActiveSupport::Deprecation.warn "ActionView::Template.finalize_compiled_template_methods is deprecated and has no effect"
+    end
+
+    def self.finalize_compiled_template_methods=(_)
+      ActiveSupport::Deprecation.warn "ActionView::Template.finalize_compiled_template_methods= is deprecated and has no effect"
+    end
 
     # === Encodings in ActionView::Template
     #
@@ -118,16 +125,6 @@ class Template
 
     attr_reader :source, :identifier, :handler, :original_encoding, :updated_at
 
-    # This finalizer is needed (and exactly with a proc inside another proc)
-    # otherwise templates leak in development.
-    Finalizer = proc do |method_name, mod| # :nodoc:
-      proc do
-        mod.module_eval do
-          remove_possible_method method_name
-        end
-      end
-    end
-
     attr_reader :variable
 
     def initialize(source, identifier, handler, details)
@@ -337,9 +334,6 @@ def #{method_name}(local_assigns, output_buffer)
         end
 
         mod.module_eval(source, identifier, 0)
-        if finalize_compiled_template_methods
-          ObjectSpace.define_finalizer(self, Finalizer[method_name, mod])
-        end
       end
 
       def handle_render_error(view, e)

actionview/test/abstract_unit.rb

@@ -48,7 +48,8 @@ def view
     @view ||= begin
       path = ActionView::FileSystemResolver.new(FIXTURE_LOAD_PATH)
       view_paths = ActionView::PathSet.new([path])
-      ActionView::Base.with_view_paths(view_paths)
+      view = ActionView::Base.with_empty_template_cache
+      view.with_view_paths(view_paths)
     end
   end
 
@@ -61,7 +62,8 @@ def render_erb(string)
       ActionView::Template.handler_for_extension(:erb),
       {})
 
-    template.render(ActionView::Base.empty, {}).strip
+    view = ActionView::Base.with_empty_template_cache
+    template.render(view.empty, {}).strip
   end
 end
 

actionview/test/activerecord/multifetch_cache_test.rb

@@ -10,8 +10,10 @@ class MultifetchCacheTest < ActiveRecordTestCase
 
   def setup
     view_paths = ActionController::Base.view_paths
+    view_paths.each(&:clear_cache)
+    ActionView::LookupContext.fallbacks.each(&:clear_cache)
 
-    @view = Class.new(ActionView::Base) do
+    @view = Class.new(ActionView::Base.with_empty_template_cache) do
       def view_cache_dependencies
         []
       end

actionview/test/template/compiled_templates_test.rb

@@ -3,7 +3,18 @@
 require "abstract_unit"
 
 class CompiledTemplatesTest < ActiveSupport::TestCase
-  teardown do
+  attr_reader :view_class
+
+  def setup
+    super
+    view_paths = ActionController::Base.view_paths
+    view_paths.each(&:clear_cache)
+    ActionView::LookupContext.fallbacks.each(&:clear_cache)
+    @view_class = ActionView::Base.with_empty_template_cache
+  end
+
+  def teardown
+    super
     ActionView::LookupContext::DetailsKey.clear
   end
 
@@ -72,13 +83,13 @@ def render(*args)
 
     def render_with_cache(*args)
       view_paths = ActionController::Base.view_paths
-      ActionView::Base.with_view_paths(view_paths, {}).render(*args)
+      view_class.with_view_paths(view_paths, {}).render(*args)
     end
 
     def render_without_cache(*args)
       path = ActionView::FileSystemResolver.new(FIXTURE_LOAD_PATH)
       view_paths = ActionView::PathSet.new([path])
-      ActionView::Base.with_view_paths(view_paths, {}).render(*args)
+      view_class.with_view_paths(view_paths, {}).render(*args)
     end
 
     def modify_template(template, content)

actionview/test/template/log_subscriber_test.rb

@@ -11,10 +11,13 @@ class AVLogSubscriberTest < ActiveSupport::TestCase
   def setup
     super
 
-    view_paths     = ActionController::Base.view_paths
+    view_paths = ActionController::Base.view_paths
+    view_paths.each(&:clear_cache)
+    ActionView::LookupContext.fallbacks.each(&:clear_cache)
+
     lookup_context = ActionView::LookupContext.new(view_paths, {}, ["test"])
     renderer       = ActionView::Renderer.new(lookup_context)
-    @view          = ActionView::Base.new(renderer, {})
+    @view          = ActionView::Base.with_empty_template_cache.new(renderer, {})
 
     ActionView::LogSubscriber.attach_to :action_view
 

actionview/test/template/render_test.rb

@@ -9,7 +9,8 @@ class TestController < ActionController::Base
 module RenderTestCases
   def setup_view(paths)
     @assigns = { secret: "in the sauce" }
-    @view = Class.new(ActionView::Base) do
+
+    @view = Class.new(ActionView::Base.with_empty_template_cache) do
       def view_cache_dependencies; []; end
 
       def combined_fragment_cache_key(key)
@@ -17,7 +18,9 @@ def combined_fragment_cache_key(key)
       end
     end.with_view_paths(paths, @assigns)
 
-    @controller_view = TestController.new.view_context
+    controller = TestController.new
+
+    @controller_view = controller.view_context_class.with_empty_template_cache.new(controller.view_renderer, controller.view_assigns, controller)
 
     # Reload and register danish language for testing
     I18n.backend.store_translations "da", {}
@@ -629,6 +632,8 @@ class CachedViewRenderTest < ActiveSupport::TestCase
   # Ensure view path cache is primed
   def setup
     view_paths = ActionController::Base.view_paths
+    view_paths.each(&:clear_cache)
+    ActionView::LookupContext.fallbacks.each(&:clear_cache)
     assert_equal ActionView::OptimizedFileSystemResolver, view_paths.first.class
     setup_view(view_paths)
   end
@@ -645,6 +650,9 @@ class LazyViewRenderTest < ActiveSupport::TestCase
   # Test the same thing as above, but make sure the view path
   # is not eager loaded
   def setup
+    view_paths = ActionController::Base.view_paths
+    view_paths.each(&:clear_cache)
+    ActionView::LookupContext.fallbacks.each(&:clear_cache)
     path = ActionView::FileSystemResolver.new(FIXTURE_LOAD_PATH)
     view_paths = ActionView::PathSet.new([path])
     assert_equal ActionView::FileSystemResolver.new(FIXTURE_LOAD_PATH), view_paths.first
@@ -704,6 +712,8 @@ class CachedCustomer < Customer; end
   setup do
     view_paths = ActionController::Base.view_paths
     assert_equal ActionView::OptimizedFileSystemResolver, view_paths.first.class
+    view_paths.each(&:clear_cache)
+    ActionView::LookupContext.fallbacks.each(&:clear_cache)
 
     ActionView::PartialRenderer.collection_cache = ActiveSupport::Cache::MemoryStore.new
 

actionview/test/template/streaming_render_test.rb

@@ -8,8 +8,11 @@ class TestController < ActionController::Base
 class SetupFiberedBase < ActiveSupport::TestCase
   def setup
     view_paths = ActionController::Base.view_paths
+    view_paths.each(&:clear_cache)
+    ActionView::LookupContext.fallbacks.each(&:clear_cache)
+
     @assigns = { secret: "in the sauce", name: nil }
-    @view = ActionView::Base.with_view_paths(view_paths, @assigns)
+    @view = ActionView::Base.with_empty_template_cache.with_view_paths(view_paths, @assigns)
     @controller_view = TestController.new.view_context
   end
 

actionview/test/template/template_test.rb

@@ -19,7 +19,8 @@ def find_template(*args)
   end
 
   class Context < ActionView::Base
-    def initialize
+    def initialize(*)
+      super
       @output_buffer = "original"
       @virtual_path = nil
     end
@@ -63,7 +64,8 @@ def render(locals = {})
   end
 
   def setup
-    @context = Context.new
+    @context = Context.with_empty_template_cache.empty
+    super
   end
 
   def test_basic_template

actionview/test/template/translation_helper_test.rb

@@ -36,7 +36,10 @@ class TranslationHelperTest < ActiveSupport::TestCase
         }
       }
     )
-    @view = ::ActionView::Base.with_view_paths(ActionController::Base.view_paths, {})
+    view_paths = ActionController::Base.view_paths
+    view_paths.each(&:clear_cache)
+    ActionView::LookupContext.fallbacks.each(&:clear_cache)
+    @view = ::ActionView::Base.with_empty_template_cache.with_view_paths(view_paths, {})
   end
 
   teardown do

guides/source/configuring.md

@@ -590,13 +590,6 @@ Defaults to `'signed cookie'`.
 
 * `config.action_view.default_enforce_utf8` determines whether forms are generated with a hidden tag that forces older versions of Internet Explorer to submit forms encoded in UTF-8. This defaults to `false`.
 
-* `config.action_view.finalize_compiled_template_methods` determines
-  whether the methods on `ActionView::CompiledTemplates` that templates
-  compile themselves to are removed when template instances are
-  destroyed by the garbage collector. This helps prevent memory leaks in
-  development mode, but for large test suites, disabling this option in
-  the test environment can improve performance. This defaults to `true`.
-
 
 ### Configuring Action Mailbox
 

railties/lib/rails/generators/rails/app/templates/config/environments/test.rb.tt

@@ -48,7 +48,4 @@ Rails.application.configure do
 
   # Raises error for missing translations.
   # config.action_view.raise_on_missing_translations = true
-
-  # Prevent expensive template finalization at end of test suite runs.
-  config.action_view.finalize_compiled_template_methods = false
 end

railties/test/application/configuration_test.rb

@@ -2094,7 +2094,9 @@ class ::DummySerializer < ActiveJob::Serializers::ObjectSerializer; end
 
     test "ActionView::Template.finalize_compiled_template_methods is true by default" do
       app "test"
-      assert_equal true, ActionView::Template.finalize_compiled_template_methods
+      assert_deprecated do
+        ActionView::Template.finalize_compiled_template_methods
+      end
     end
 
     test "ActionView::Template.finalize_compiled_template_methods can be configured via config.action_view.finalize_compiled_template_methods" do
@@ -2106,7 +2108,9 @@ class ::DummySerializer < ActiveJob::Serializers::ObjectSerializer; end
 
       app "test"
 
-      assert_equal false, ActionView::Template.finalize_compiled_template_methods
+      assert_deprecated do
+        ActionView::Template.finalize_compiled_template_methods
+      end
     end
 
     test "ActiveJob::Base.return_false_on_aborted_enqueue is true by default" do