Update to use Subscriber#start instead

We don't need to instrument another event as
`ActiveSupport::LogSubscriber` already tracks when the instrumentation
starts.

Close #23717

2 files changed, 15 insertions, 7 deletions

diff --git a/actionview/lib/action_view/log_subscriber.rb b/actionview/lib/action_view/log_subscriber.rb
index 2d59033cb3..5a29c68214 100644
--- a/actionview/lib/action_view/log_subscriber.rb
+++ b/actionview/lib/action_view/log_subscriber.rb
@@ -30,13 +30,12 @@ module ActionView
       end
     end
 
-
-    def start_rendering(event)
-      info do
-        message = "Rendering #{from_rails_root(event.payload[:identifier])}"
-        message << " within #{from_rails_root(event.payload[:layout])}" if event.payload[:layout]
-        message
+    def start(name, id, payload)
+      if name == "render_template.action_view"
+        log_rendering_start(payload)
       end
+
+      super
     end
 
     def logger
@@ -63,6 +62,16 @@ module ActionView
         "[#{payload[:count]} times]"
       end
     end
+
+  private
+
+    def log_rendering_start(payload)
+      info do
+        message = "  Rendering #{from_rails_root(payload[:identifier])}"
+        message << " within #{from_rails_root(payload[:layout])}" if payload[:layout]
+        message
+      end
+    end
   end
 end
 
diff --git a/actionview/lib/action_view/renderer/template_renderer.rb b/actionview/lib/action_view/renderer/template_renderer.rb
index fd550d95e1..9d15bbfca7 100644
--- a/actionview/lib/action_view/renderer/template_renderer.rb
+++ b/actionview/lib/action_view/renderer/template_renderer.rb
@@ -50,7 +50,6 @@ module ActionView
       view, locals = @view, locals || {}
 
       render_with_layout(layout_name, locals) do |layout|
-        ActiveSupport::Notifications.instrument("start_rendering.action_view", identifier: template.identifier, layout: layout.try(:virtual_path))
         instrument(:template, :identifier => template.identifier, :layout => layout.try(:virtual_path)) do
           template.render(view, locals) { |*name| view._layout_for(*name) }
         end