Add tracer benchmark suite

Author: samuel-williams-shopify

bake.rb

@@ -24,6 +24,11 @@ def before_test
 	build
 end
 
+def benchmark
+	build
+	system("sus --verbose benchmark")
+end
+
 # Update the project documentation with the new version number.
 #
 # @parameter version [String] The new version number.

benchmark/tracer.rb

@@ -0,0 +1,82 @@
+# frozen_string_literal: true
+
+# Released under the MIT License.
+# Copyright, 2026, by Samuel Williams.
+
+require_relative "../config/environment"
+
+require "coverage"
+require "sus/fixtures/benchmark"
+require "tmpdir"
+
+require "ruby/coverage"
+
+describe Ruby::Coverage::Tracer do
+	include Sus::Fixtures::Benchmark
+	
+	SAMPLES = 8
+	
+	def around
+		Dir.mktmpdir do |root|
+			@path = File.join(root, "workload.rb")
+			
+			File.write(@path, <<~RUBY)
+				i = 0
+				total = 0
+				while i < 1_000_000
+					total += i
+					i += 1
+				end
+				total
+			RUBY
+			
+			yield
+		end
+	end
+	
+	attr :path
+	
+	def stop_standard_coverage
+		if ::Coverage.running?
+			::Coverage.result(stop: true, clear: true)
+		end
+	end
+	
+	measure "load without coverage" do |repeats|
+		repeats.exactly(SAMPLES).times do
+			load(self.path)
+		end
+	end
+	
+	measure "load with stdlib coverage" do |repeats|
+		repeats.exactly(SAMPLES).times do
+			begin
+				::Coverage.start(lines: true)
+				load(self.path)
+			ensure
+				stop_standard_coverage
+			end
+		end
+	end
+	
+	measure "load with ruby coverage" do |repeats|
+		repeats.exactly(SAMPLES).times do
+			tracer = Ruby::Coverage::Tracer.new do |_path, iseq|
+				counts = []
+				
+				Ruby::Coverage.executable_lines(iseq).each do |line|
+					counts[line] = 0
+				end
+				
+				counts
+			end
+			
+			begin
+				tracer.start
+				load(self.path)
+			ensure
+				tracer.stop
+			end
+		end
+	end
+end

gems.rb

@@ -21,6 +21,7 @@
 
 group :test do
 	gem "sus"
+	gem "sus-fixtures-benchmark"
 	gem "covered"
 
 	gem "rubocop"