📉⚡️ Add vernier profiler for tests/benchmarks

Export `NET_IMAP_PROFILE=1` before running tests or benchmarks.
Profiling data will be written to `~/.cache/net-imap`, or export
`NET_IMAP_PROFILE_OUTDIR=dirname` to configure the output dir.

Author: nevans

Gemfile

@@ -16,6 +16,7 @@ gem "test-unit-ruby-core", git: "https://github.com/ruby/test-unit-ruby-core"
 
 gem "benchmark", require: false
 gem "benchmark-driver", require: false
+gem "vernier", require: false
 
 group :test do
   gem "simplecov",        require: false

benchmarks/sequence_set-new.yml

@@ -4,6 +4,9 @@ prelude: |
   require "net/imap"
   SeqSet = Net::IMAP::SequenceSet
 
+  require "./test/lib/profiling_helper"
+  include ProfilingHelper
+
   N_RAND = 100
 
   def rand_nums(n, min: 1, max: (n * 1.25).to_i) = Array.new(n) { rand(1..max) }
@@ -12,10 +15,12 @@ prelude: |
 
   def build_string_inputs(n, n_rand, **)
     Array.new(n_rand) { rand_string(n, **) }
+      .tap { profile_until_exit("seqset-new-#{n}-string") }
   end
 
   def build_int_inputs(n, n_rand, **)
     Array.new(n_rand) { rand_entries(n, **) }
+      .tap { profile_until_exit("seqset-new-#{n}-int") }
   end
 
   inputs = nil

test/lib/helper.rb

@@ -55,3 +55,5 @@ def assert_pattern
   end
 
 end
+
+require_relative "profiling_helper"

test/lib/profiling_helper.rb

@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+module ProfilingHelper
+  module_function
+
+  def profile?            = ENV["NET_IMAP_PROFILE"] in /\A(1|t|true|on|yes)\z/i
+  def start_profiler(...) = if profile? then start_profiler!(...) end
+  def stop_profiler       = if profile? then stop_profiler!       end
+  def stop_profiler!      = Vernier.stop_profile
+
+  def profile_until_exit(...)
+    return unless profile?
+    start_profiler!(...)
+    at_exit { stop_profiler }
+  end
+
+  def start_profiler!(name, **)
+    require "vernier"
+    require "fileutils"
+
+    outdir = ENV.fetch("NET_IMAP_PROFILE_OUTDIR") {
+      cache_dir = ENV.fetch("XDG_CACHE_HOME", File.join(Dir.home, ".cache"))
+      File.join(cache_dir, "net-imap")
+    }
+    outfile = "prof-#{name}-#{Time.now.iso8601}.json.gz"
+    out = File.join(outdir, outfile)
+
+    FileUtils.mkdir_p outdir
+    Vernier.start_profile(out:, **)
+  end
+end

test/net/imap/test_sequence_set.rb

@@ -8,6 +8,11 @@ class IMAPSequenceSetTest < Test::Unit::TestCase
   SequenceSet     = Net::IMAP::SequenceSet
   DataFormatError = Net::IMAP::DataFormatError
 
+  if ProfilingHelper.profile?
+    def self.startup  = ProfilingHelper.start_profiler("seqset-tests")
+    def self.shutdown = ProfilingHelper.stop_profiler
+  end
+
   def compare_to_reference_set(nums, set, seqset)
     set.merge nums
     seqset.merge nums