Fix total_render_time if a Profiler gets used for multiple renders

lib/liquid/profiler.rb

@@ -90,14 +90,20 @@ module Liquid
     def initialize
       @root_timing  = Timing.new("", nil)
       @timing_stack = [@root_timing]
+      @render_start_at = nil
+      @total_render_time = 0.0
     end
 
-    def start
-      @render_start_at = monotonic_time
-    end
-
-    def stop
-      @total_render_time = monotonic_time - @render_start_at
+    def profile
+      return yield if @render_start_at
+      started_at = monotonic_time
+      begin
+        @started_at = started_at
+        yield
+      ensure
+        @started_at = nil
+        @total_render_time += monotonic_time - started_at
+      end
     end
 
     def each(&block)

lib/liquid/template.rb

@@ -193,6 +193,10 @@ module Liquid
       # Retrying a render resets resource usage
       context.resource_limits.reset
 
+      if @profiling && context.profiler.nil?
+        @profiler = context.profiler = Liquid::Profiler.new
+      end
+
       begin
         # render the nodelist.
         with_profiling(context) do
@@ -221,18 +225,8 @@ module Liquid
     end
 
     def with_profiling(context)
-      if @profiling && context.profiler.nil?
-        @profiler = context.profiler = Profiler.new
-        @profiler.start
-
-        begin
-          yield
-        ensure
-          @profiler.stop
-        end
-      else
-        yield
-      end
+      return yield unless context.profiler
+      context.profiler.profile { yield }
     end
 
     def apply_options_to_context(context, options)