action_view memoize partials

config/initializers/backtrace_cleaning.rb

@@ -1,3 +1,2 @@
-bc = Rails.backtrace_cleaner
-# bc.add_silencer { |line| %r{^lib/(monkey_patches|semantic)}.match?(line) }
-bc.add_silencer { |line| %r{^lib/(monkey_patches)}.match?(line) }
+Rails.backtrace_cleaner
+     .add_silencer { |line| %r{^lib/(monkey_patches)}.match?(line) }

lib/semantic/abstract_formatter.rb

@@ -28,11 +28,9 @@ module Semantic
 
       clazz = colorize("#{exc.class}\n", color_map[:fatal])
       message = colorize(exc.message.chomp(''), color_map[:error])
-
-      # TODO: backtrace_cleaner might be optionally disable from Live::Constant
-      backtrace = stackisize(Rails.backtrace_cleaner.clean(exc.backtrace))
-
-      "#{clazz}#{message}#{backtrace}"
+      backtrace = exc.backtrace
+      stack = Helper.stackisize(*backtrace)
+      ["#{clazz}#{message}", stack].compact.join("\n")
     end
 
     def origin
@@ -41,21 +39,6 @@ module Semantic
       colorize(centerize(log.name), taint)
     end
 
-    def ansi_trace(trace, symbol)
-      match = trace.match(/(↳ )?(.*:\d+)(:in `)?(.*'?)/) # only m2(=file) and m4(=optional function) are useful
-      return trace unless match
-
-      _, m2, _, m4 = match.captures
-      "#{symbol} #{m2} #{BOLD}#{m4.chop}#{CLEAR}"
-    end
-
-    def stackisize(items)
-      return '' if items.empty?
-
-      traces = items.map { |item| ansi_trace(item, '➟') }
-      "\n#{traces.join("\n")}"
-    end
-
     def tags
       first_tag, taint = log.tags.empty? ? [TAG_NONE, CLEAR] : [log.tags.first, BG_GRAY + TEXT_YELLOW]
       colorize(centerize(first_tag, TAG_FIXED_LENGTH), taint)

lib/semantic/helper.rb

@@ -0,0 +1,26 @@
+module Semantic
+  # useful public functions
+  module Helper
+    class << self
+      include AnsiColors
+      def stackisize(*items)
+        return if items.empty?
+
+        Rails.backtrace_cleaner
+             .clean(items)
+             .map { |item| ansi_trace(item, '➟') }
+             .join("\n")
+      end
+
+      private
+
+      def ansi_trace(trace, symbol)
+        match = trace.match(/(↳ )?(.*:\d+)(:in `)?(.*'?)/) # only m2(=file) and m4(=optional function) are useful
+        return trace unless match
+
+        _, m2, _, m4 = match.captures
+        "#{symbol} #{m2} #{BOLD}#{m4.chop}#{CLEAR}"
+      end
+    end
+  end
+end

lib/semantic/subscribers/action_view.rb

@@ -6,12 +6,19 @@ module Semantic
 
       REGEX_BASEDIR = %r{^#{Rails.root}/(.*)}
 
-      def initialize(*) = super(:view)
+      def initialize(*)
+        super(:view)
+        @partials = {}
+      end
 
       def render_partial(event)
         identifier = pathname(event.payload[:identifier])
-        # logger.debug("Rendered partial #{identifier}", event.payload[:locals]) if identifier
-        logger.debug("Rendered partial #{identifier}") if identifier
+        partial_savings = @partials[event.transaction_id] ||= {}
+        partial_saving = partial_savings[identifier] ||= {
+          count: 0,
+          first_origin: Rails.backtrace_cleaner.clean(caller)[1]
+        }
+        partial_saving[:count] += 1
       end
 
       def render_template(event)
@@ -19,23 +26,47 @@ module Semantic
         return unless layout
 
         identifier = pathname(event.payload[:identifier])
-        logger.debug { "Rendered template #{identifier}" } if identifier
+        return unless identifier
+
+        logger.debug do
+          pop_partial_savings(event.transaction_id)
+          "Rendered template #{identifier}"
+        end
       end
 
       def render_collection(event)
         identifier = pathname(event.payload[:identifier])
+        return unless identifier
+
         count = event.payload[:count]
         cache_hits = event.payload[:cache_hits] || 0
-        logger.debug { "Rendered collection #{identifier} (#{count} times, #{cache_hits} cached)" } if identifier
+        logger.debug do
+          pop_partial_savings(event.transaction_id)
+          "Rendered collection #{identifier} (#{count} times, #{cache_hits} cached)"
+        end
       end
 
       def render_layout(event)
         identifier = pathname(event.payload[:identifier])
-        logger.debug { "Rendered layout #{identifier}" } if identifier
+        return unless identifier
+
+        logger.debug do
+          pop_partial_savings(event.transaction_id)
+          "Rendered layout #{identifier}"
+        end
       end
 
       private
 
+      def pop_partial_savings(transaction_id)
+        partial_savings = @partials.delete(transaction_id)
+        partial_savings.each do |partial, saving|
+          count_info = " (#{saving[:count]} times)" if saving[:count] > 1
+          logger.debug("Rendered partial #{partial}#{count_info}")
+          logger.debug(Semantic::Helper.stackisize(saving[:first_origin]))
+        end
+      end
+
       def pathname(location)
         m = REGEX_BASEDIR.match(location)
         m[1] if m