count_const_refs.rb

def count_constant_refs(iseq)
  cached = false

  iseq.last.each_with_object([]) do |insn, counts|
    case insn
    in [:opt_getinlinecache, *]
      cached = true
      counts << 0
    in [:getconstant, *]
      counts[counts.length - 1] += 1 if cached
    in [:opt_setinlinecache, *]
      cached = false
    in [*, ["YARVInstructionSequence/SimpleDataFormat", *] => child, *]
      counts.concat(count_constant_refs(child))
    else
    end
  end
end

[].tap do |counts|
  Dir["**/*.rb"].each do |filepath|
    iseq = RubyVM::InstructionSequence.compile_file(filepath).to_a
    counts << count_constant_refs(iseq)
  rescue SyntaxError
  end

  n, d = counts.sum(&:length), counts.length
  puts "Average const refs per file: #{n}/#{d} = #{(n.to_f / d).round(2)}"

  n, d = counts.sum(&:sum), n
  puts "Average const ref depth: #{n}/#{d} = #{(n.to_f / d).round(2)}"
end