Merge pull request #34952 from rails/template-stuff

Template Handler Refactoring

11 files changed, 43 insertions, 82 deletions

diff --git a/actionpack/lib/action_controller/metal/basic_implicit_render.rb b/actionpack/lib/action_controller/metal/basic_implicit_render.rb
index 2dc990f303..f9a758ff0e 100644
--- a/actionpack/lib/action_controller/metal/basic_implicit_render.rb
+++ b/actionpack/lib/action_controller/metal/basic_implicit_render.rb
@@ -6,7 +6,7 @@ module ActionController
       super.tap { default_render unless performed? }
     end
 
-    def default_render(*args)
+    def default_render
       head :no_content
     end
   end
diff --git a/actionpack/lib/action_controller/metal/implicit_render.rb b/actionpack/lib/action_controller/metal/implicit_render.rb
index d3bb58f48b..8365ddca57 100644
--- a/actionpack/lib/action_controller/metal/implicit_render.rb
+++ b/actionpack/lib/action_controller/metal/implicit_render.rb
@@ -30,9 +30,9 @@ module ActionController
     # :stopdoc:
     include BasicImplicitRender
 
-    def default_render(*args)
+    def default_render
       if template_exists?(action_name.to_s, _prefixes, variants: request.variant)
-        render(*args)
+        render
       elsif any_templates?(action_name.to_s, _prefixes)
         message = "#{self.class.name}\##{action_name} is missing a template " \
           "for this request format and variant.\n" \
diff --git a/actionpack/lib/action_dispatch/testing/assertions/routing.rb b/actionpack/lib/action_dispatch/testing/assertions/routing.rb
index af41521c5c..28cde6704e 100644
--- a/actionpack/lib/action_dispatch/testing/assertions/routing.rb
+++ b/actionpack/lib/action_dispatch/testing/assertions/routing.rb
@@ -160,9 +160,16 @@ module ActionDispatch
           @controller.singleton_class.include(_routes.url_helpers)
 
           if @controller.respond_to? :view_context_class
-            @controller.view_context_class = Class.new(@controller.view_context_class) do
+            view_context_class = Class.new(@controller.view_context_class) do
               include _routes.url_helpers
             end
+
+            custom_view_context = Module.new {
+              define_method(:view_context_class) do
+                view_context_class
+              end
+            }
+            @controller.extend(custom_view_context)
           end
         end
         yield @routes
diff --git a/actionpack/test/controller/new_base/render_context_test.rb b/actionpack/test/controller/new_base/render_context_test.rb
deleted file mode 100644
index 5e570a1d79..0000000000
--- a/actionpack/test/controller/new_base/render_context_test.rb
+++ /dev/null
@@ -1,55 +0,0 @@
-# frozen_string_literal: true
-
-require "abstract_unit"
-
-# This is testing the decoupling of view renderer and view context
-# by allowing the controller to be used as view context. This is
-# similar to the way sinatra renders templates.
-module RenderContext
-  class BasicController < ActionController::Base
-    self.view_paths = [ActionView::FixtureResolver.new(
-      "render_context/basic/hello_world.html.erb" => "<%= @value %> from <%= self.__controller_method__ %>",
-      "layouts/basic.html.erb" => "?<%= yield %>?"
-    )]
-
-    # 1) Include ActionView::Context to bring the required dependencies
-    include ActionView::Context
-
-    # 2) Call _prepare_context that will do the required initialization
-    before_action :_prepare_context
-
-    def hello_world
-      @value = "Hello"
-      render action: "hello_world", layout: false
-    end
-
-    def with_layout
-      @value = "Hello"
-      render action: "hello_world", layout: "basic"
-    end
-
-    protected def __controller_method__
-      "controller context!"
-    end
-
-    private
-      # 3) Set view_context to self
-      def view_context
-        self
-      end
-  end
-
-  class RenderContextTest < Rack::TestCase
-    test "rendering using the controller as context" do
-      get "/render_context/basic/hello_world"
-      assert_body "Hello from controller context!"
-      assert_status 200
-    end
-
-    test "rendering using the controller as context with layout" do
-      get "/render_context/basic/with_layout"
-      assert_body "?Hello from controller context!?"
-      assert_status 200
-    end
-  end
-end
diff --git a/actionview/lib/action_view/base.rb b/actionview/lib/action_view/base.rb
index d41fe2a608..6cb342a0a9 100644
--- a/actionview/lib/action_view/base.rb
+++ b/actionview/lib/action_view/base.rb
@@ -10,6 +10,10 @@ require "action_view/template"
 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.
@@ -141,6 +145,8 @@ module ActionView #: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 }
 
@@ -210,6 +216,18 @@ module ActionView #:nodoc:
       _prepare_context
     end
 
+    def run(method, locals, buffer, &block)
+      _old_output_buffer, _old_virtual_path = @output_buffer, @virtual_path
+      @output_buffer = buffer
+      send(method, locals, buffer, &block)
+    ensure
+      @output_buffer, @virtual_path = _old_output_buffer, _old_virtual_path
+    end
+
+    def compiled_method_container
+      CompiledTemplates
+    end
+
     ActiveSupport.run_load_hooks(:action_view, self)
   end
 end
diff --git a/actionview/lib/action_view/context.rb b/actionview/lib/action_view/context.rb
index 3c605c3ee3..2b22c30a3a 100644
--- a/actionview/lib/action_view/context.rb
+++ b/actionview/lib/action_view/context.rb
@@ -1,10 +1,6 @@
 # frozen_string_literal: true
 
 module ActionView
-  module CompiledTemplates #:nodoc:
-    # holds compiled template code
-  end
-
   # = Action View Context
   #
   # Action View contexts are supplied to Action Controller to render a template.
@@ -16,7 +12,6 @@ module ActionView
   # object that includes this module (although you can call _prepare_context
   # defined below).
   module Context
-    include CompiledTemplates
     attr_accessor :output_buffer, :view_flow
 
     # Prepares the context by setting the appropriate instance variables.
diff --git a/actionview/lib/action_view/rendering.rb b/actionview/lib/action_view/rendering.rb
index cb4327cf16..205665a8c6 100644
--- a/actionview/lib/action_view/rendering.rb
+++ b/actionview/lib/action_view/rendering.rb
@@ -55,10 +55,8 @@ module ActionView
       end
     end
 
-    attr_internal_writer :view_context_class
-
     def view_context_class
-      @_view_context_class ||= self.class.view_context_class
+      self.class.view_context_class
     end
 
     # An instance of a view class. The default view class is ActionView::Base.
diff --git a/actionview/lib/action_view/template.rb b/actionview/lib/action_view/template.rb
index 070d82cf17..8ce8053011 100644
--- a/actionview/lib/action_view/template.rb
+++ b/actionview/lib/action_view/template.rb
@@ -155,10 +155,10 @@ module ActionView
     # This method is instrumented as "!render_template.action_view". Notice that
     # we use a bang in this instrumentation because you don't want to
     # consume this in production. This is only slow if it's being listened to.
-    def render(view, locals, buffer = nil, &block)
+    def render(view, locals, buffer = ActionView::OutputBuffer.new, &block)
       instrument_render_template do
         compile!(view)
-        view.send(method_name, locals, buffer, &block)
+        view.run(method_name, locals, buffer, &block)
       end
     rescue => e
       handle_render_error(view, e)
@@ -264,11 +264,7 @@ module ActionView
           # re-compilation
           return if @compiled
 
-          if view.is_a?(ActionView::CompiledTemplates)
-            mod = ActionView::CompiledTemplates
-          else
-            mod = view.singleton_class
-          end
+          mod = view.compiled_method_container
 
           instrument("!compile_template") do
             compile(mod)
@@ -301,9 +297,7 @@ module ActionView
         # encoding of the code
         source = +<<-end_src
           def #{method_name}(local_assigns, output_buffer)
-            _old_virtual_path, @virtual_path = @virtual_path, #{@virtual_path.inspect};_old_output_buffer = @output_buffer;#{locals_code};#{code}
-          ensure
-            @virtual_path, @output_buffer = _old_virtual_path, _old_output_buffer
+            @virtual_path = #{@virtual_path.inspect};#{locals_code};#{code}
           end
         end_src
 
diff --git a/actionview/lib/action_view/template/handlers/erb/erubi.rb b/actionview/lib/action_view/template/handlers/erb/erubi.rb
index db75f028ed..e155bae89d 100644
--- a/actionview/lib/action_view/template/handlers/erb/erubi.rb
+++ b/actionview/lib/action_view/template/handlers/erb/erubi.rb
@@ -13,7 +13,7 @@ module ActionView
 
             # Dup properties so that we don't modify argument
             properties = Hash[properties]
-            properties[:preamble]   = "@output_buffer = output_buffer || ActionView::OutputBuffer.new;"
+            properties[:preamble]   = ""
             properties[:postamble]  = "@output_buffer.to_s"
             properties[:bufvar]     = "@output_buffer"
             properties[:escapefunc] = ""
@@ -22,8 +22,12 @@ module ActionView
           end
 
           def evaluate(action_view_erb_handler_context)
-            pr = eval("proc { #{@src} }", binding, @filename || "(erubi)")
-            action_view_erb_handler_context.instance_eval(&pr)
+            src = @src
+            view = Class.new(ActionView::Base) {
+              include action_view_erb_handler_context._routes.url_helpers
+              class_eval("define_method(:_template) { |local_assigns, output_buffer| #{src} }", @filename || "(erubi)", 0)
+            }.new(action_view_erb_handler_context)
+            view.run(:_template, {}, ActionView::OutputBuffer.new)
           end
 
         private
diff --git a/actionview/test/abstract_unit.rb b/actionview/test/abstract_unit.rb
index f90626ad9e..d71944e938 100644
--- a/actionview/test/abstract_unit.rb
+++ b/actionview/test/abstract_unit.rb
@@ -61,7 +61,7 @@ module RenderERBUtils
       ActionView::Template::Handlers::ERB,
       {})
 
-    template.render(self, {}).strip
+    template.render(ActionView::Base.new, {}).strip
   end
 end
 
diff --git a/actionview/test/template/template_test.rb b/actionview/test/template/template_test.rb
index b348d1f17b..8257d97b7c 100644
--- a/actionview/test/template/template_test.rb
+++ b/actionview/test/template/template_test.rb
@@ -18,7 +18,7 @@ class TestERBTemplate < ActiveSupport::TestCase
     attr_accessor :formats
   end
 
-  class Context
+  class Context < ActionView::Base
     def initialize
       @output_buffer = "original"
       @virtual_path = nil