Add bin/steep-check for profiling

Gemfile

@@ -12,3 +12,8 @@ end
 gem 'minitest-slow_test'
 
 gem "debug", require: false, platform: :mri
+gem "vernier", "~> 1.0"
+gem "memory_profiler"
+
+gem "rbs"
+gem "majo"

Gemfile.lock

@@ -54,6 +54,8 @@ GEM
       rb-fsevent (~> 0.10, >= 0.10.3)
       rb-inotify (~> 0.9, >= 0.9.10)
     logger (1.6.0)
+    majo (1.0.0)
+    memory_profiler (1.0.2)
     minitest (5.24.1)
     minitest-hooks (1.5.1)
       minitest (> 5.3)
@@ -86,18 +88,23 @@ GEM
     tzinfo (2.0.6)
       concurrent-ruby (~> 1.0)
     unicode-display_width (2.5.0)
+    vernier (1.1.1)
 
 PLATFORMS
   ruby
 
 DEPENDENCIES
   debug
+  majo
+  memory_profiler
   minitest (~> 5.21)
   minitest-hooks
   minitest-slow_test
   rake
+  rbs
   stackprof
   steep!
+  vernier (~> 1.0)
 
 BUNDLED WITH
    2.3.8

bin/mem_graph.rb

@@ -0,0 +1,67 @@
+class MemGraph
+  attr_reader :edges
+
+  attr_reader :checked
+
+  attr_reader :generation
+
+  def initialize(generation)
+    @generation = generation
+    @edges = []
+    @checked = Set.new.compare_by_identity
+    @checked << self
+    @checked << edges
+    @checked << checked
+  end
+
+  IVARS = Object.instance_method(:instance_variables)
+  IVGET = Object.instance_method(:instance_variable_get)
+
+  def traverse(object)
+    return if checked.include?(object)
+    checked << object
+
+    case object
+    when Array
+      object.each do |value|
+        insert_edge(object, value)
+        traverse(value)
+      end
+    when Hash
+      object.each do |key, value|
+        insert_edge(object, key)
+        insert_edge(object, value)
+
+        traverse(key)
+        traverse(value)
+      end
+    else
+      IVARS.bind_call(object).each do |name|
+        if name.is_a?(Symbol)
+          value = IVGET.bind_call(object, name)
+          traverse(value)
+          insert_edge(object, value)
+        else
+          STDERR.puts "Unexpected instance variable name: #{name} in #{object.class}"
+        end
+      end
+    end
+  end
+
+  def insert_edge(source, dest)
+    case dest
+    when Integer, Symbol, nil, true, false, Float
+    else
+      edges << [
+        "#{source.class}(#{source.__id__})",
+        "#{dest.class}(#{dest.__id__})",
+      ]
+    end
+  end
+
+  def dot
+    "digraph G {\n" + edges.uniq.map do |source, dest|
+      "  #{source} -> #{dest};"
+    end.join("\n") + "}"
+  end
+end

bin/mem_prof.rb

@@ -0,0 +1,102 @@
+require "objspace"
+
+class MemProf
+  attr_reader :generation
+
+  def initialize
+  end
+
+  def self.trace(io: STDOUT, &block)
+    profiler = MemProf.new
+    profiler.start
+
+    begin
+      ret = yield
+    rescue
+      ObjectSpace.trace_object_allocations_stop
+      ObjectSpace.trace_object_allocations_clear
+      raise
+    end
+
+    allocated, retained, collected = profiler.stop
+
+    counts = {}
+    collected.each do |id, entry|
+      counts[entry] ||= 0
+      counts[entry] += 1
+    end
+
+    counts.keys.sort_by {|entry| -counts[entry] }.take(200).each do |entry|
+      count = counts.fetch(entry)
+      io.puts "#{entry[0]},#{entry[1]},#{entry[2]},#{count}"
+    end
+
+    STDERR.puts "Total allocated: #{allocated.size}"
+    STDERR.puts "Total retained: #{retained.size}"
+    STDERR.puts "Total collected: #{collected.size}"
+
+    ret
+  end
+
+  def start
+    GC.disable
+    3.times { GC.start }
+    GC.start
+
+    @generation = GC.count
+    ObjectSpace.trace_object_allocations_start
+  end
+
+  def stop
+    ObjectSpace.trace_object_allocations_stop
+
+    allocated = objects()
+    retained = {}
+
+    GC.enable
+    GC.start
+    GC.start
+    GC.start
+
+    ObjectSpace.each_object do |obj|
+      next unless ObjectSpace.allocation_generation(obj) == generation
+      if o = allocated[obj.__id__]
+        retained[obj.__id__] = o
+      end
+    end
+
+    # ObjectSpace.trace_object_allocations_clear
+
+    collected = {}
+    allocated.each do |id, state|
+      collected[id] = state unless retained.key?(id)
+    end
+
+    [allocated, retained, collected]
+  end
+
+  def objects(hash = {})
+    ObjectSpace.each_object do |obj|
+      next unless ObjectSpace.allocation_generation(obj) == generation
+
+      file = ObjectSpace.allocation_sourcefile(obj) || "(no name)"
+      line = ObjectSpace.allocation_sourceline(obj)
+      klass = object_class(obj)
+
+      hash[obj.__id__] = [file, line, klass]
+    end
+
+    hash
+  end
+
+  KERNEL_CLASS_METHOD = Kernel.instance_method(:class)
+  def object_class(obj)
+    klass = obj.class rescue nil
+
+    unless Class === klass
+      # attempt to determine the true Class when .class returns something other than a Class
+      klass = KERNEL_CLASS_METHOD.bind_call(obj)
+    end
+    klass
+  end
+end