Minor performance improvements

Author: BlakeWilliams

lib/view_component/base.rb

@@ -72,17 +72,17 @@ def render_in(view_context, &block)
 
       # TODO flag with initializer
       if !self.__vc_original_view_context
-        view_context.original_output_buffer = ActionView::OutputBuffer.new if !view_context.output_buffer
+        view_context.output_buffer = ActionView::OutputBuffer.new if !view_context.output_buffer
         self.__vc_original_view_context ||= view_context
         if self.__vc_original_view_context.global_buffer_coordinator.nil?
           coordinator = self.__vc_original_view_context.global_buffer_coordinator = GlobalBuffer::Coordinator.new
-          coordinator.subscribers.push(self.__vc_original_view_context)
+          coordinator.subscribe(self.__vc_original_view_context)
         end
       end
 
       @output_buffer = self.__vc_original_view_context.output_buffer
       self.global_buffer_coordinator = self.__vc_original_view_context.global_buffer_coordinator
-      self.__vc_original_view_context.global_buffer_coordinator.subscribers.push(self)
+      self.__vc_original_view_context.global_buffer_coordinator.subscribe(self)
 
       @lookup_context ||= view_context.lookup_context
 
@@ -114,18 +114,17 @@ def render_in(view_context, &block)
       @__vc_content_evaluated = false
       @__vc_render_in_block = block
 
-      self.__vc_original_view_context.capture do
-        before_render
+      before_render
 
-        if render?
-          capture do
-            render_template_for(@__vc_variant).to_s + _output_postamble
-          end
-        else
-          ""
+      if render?
+        capture do
+          render_template_for(@__vc_variant).to_s + _output_postamble
         end
+      else
+        ""
       end
     ensure
+      global_buffer_coordinator&.unsubscribe(self)
       @current_template = old_current_template
     end
 

lib/view_component/global_buffer.rb

@@ -4,12 +4,22 @@ module ViewComponent
   # TODO if things break, log each time an unsafe string method is called
   module GlobalBuffer
     class Coordinator
+      attr_reader :subscribers
+
       def initialize
-        @subscribers = []
+        @subscribers = Set.new
+      end
+
+      def subscribe(subscriber)
+        @subscribers << subscriber
+      end
+
+      def unsubscribe(subscriber)
+        @subscribers.delete(subscriber)
       end
 
-      def subscribers
-        @subscribers
+      def clear
+        @subscribers = []
       end
     end
 
@@ -24,33 +34,31 @@ def with_output_buffer(buf = nil) # :nodoc:
             end
           end
           self.output_buffer, old_buffer = buf, output_buffer
-          global_buffer_coordinator&.subscribers&.each { |s| s.output_buffer = buf}
+          global_buffer_coordinator.subscribers.each { |s| s.output_buffer = buf} if global_buffer_coordinator
           yield
           output_buffer
         ensure
           self.output_buffer = old_buffer
-          global_buffer_coordinator&.subscribers&.each { |s| s.output_buffer = old_buffer }
+          global_buffer_coordinator.subscribers.each { |s| s.output_buffer = old_buffer } if global_buffer_coordinator
         end
 
         def _run(method, template, locals, buffer, add_to_stack: true, &block)
           _old_output_buffer, _old_virtual_path, _old_template = @output_buffer, @virtual_path, @current_template
           @current_template = template if add_to_stack
           @output_buffer = buffer
-          global_buffer_coordinator&.subscribers&.each { |s| s.output_buffer = buffer }
+          global_buffer_coordinator.subscribers.each { |s| s.output_buffer = buffer } if global_buffer_coordinator
           public_send(method, locals, buffer, &block)
         ensure
           @output_buffer, @virtual_path, @current_template = _old_output_buffer, _old_virtual_path, _old_template
-          global_buffer_coordinator&.subscribers&.each { |s| s.output_buffer = _old_output_buffer }
+          global_buffer_coordinator.subscribers.each { |s| s.output_buffer = _old_output_buffer } if global_buffer_coordinator
         end
       end
 
       included do
         attr_accessor :global_buffer_coordinator
+        alias_method(:original_with_output_buffer, :with_output_buffer)
 
-        alias_method(:original_output_buffer=, :output_buffer=)
         prepend Compatibility
-
-        alias_method(:original_with_output_buffer, :with_output_buffer)
       end
     end
   end

lib/view_component/slot_v2.rb

@@ -45,18 +45,12 @@ def to_s
           if defined?(@__vc_content_set_by_with_content)
             @__vc_component_instance.with_content(@__vc_content_set_by_with_content)
 
-            view_context.capture do
-              @__vc_component_instance.render_in(view_context)
-            end
+            @__vc_component_instance.render_in(view_context)
           elsif defined?(@__vc_content_block)
-            view_context.capture do
-              # render_in is faster than `parent.render`
-              @__vc_component_instance.render_in(view_context, &@__vc_content_block)
-            end
+            # render_in is faster than `parent.render`
+            @__vc_component_instance.render_in(view_context, &@__vc_content_block)
           else
-            view_context.capture do
-              @__vc_component_instance.render_in(view_context)
-            end
+            @__vc_component_instance.render_in(view_context)
           end
         elsif defined?(@__vc_content)
           @__vc_content

performance/benchmark.rb

@@ -18,15 +18,25 @@ class BenchmarksController < ActionController::Base
 end
 
 BenchmarksController.view_paths = [File.expand_path("./views", __dir__)]
-controller_view = BenchmarksController.new.view_context
 
 Benchmark.ips do |x|
   x.time = 10
   x.warmup = 2
 
-  x.report("component:") { controller_view.render(Performance::NameComponent.new(name: "Fox Mulder")) }
-  x.report("inline:") { controller_view.render(Performance::InlineComponent.new(name: "Fox Mulder")) }
-  x.report("partial:") { controller_view.render("partial", name: "Fox Mulder") }
+  x.report("component:") do
+    controller_view = BenchmarksController.new.view_context
+    controller_view.render(Performance::NameComponent.new(name: "Fox Mulder"))
+  end
+
+  x.report("inline:") do
+    controller_view = BenchmarksController.new.view_context
+    controller_view.render(Performance::InlineComponent.new(name: "Fox Mulder"))
+  end
+
+  x.report("partial:") do
+    controller_view = BenchmarksController.new.view_context
+    controller_view.render("partial", name: "Fox Mulder")
+  end
 
   x.compare!
 end