Code from my bisect experiment

bisect_flakey_specs.rb

module ListBisector
  # anything that responds to call: block, lambda, method
  # the function being called needs to perform a function against 2 bounded(eg. has length), enumerable objects(eg. has each)
  def bisect(a, b, &block)
    a_result = block.call(a)
    b_result = block.call(b)
    
    if a_result == b_result
      puts "done: both sets are interesting or uninteresting, we're done"
      [a, b]
    elsif a_result
      puts "next: splitting a"
      bisect(first_half(a), second_half(a), &block)
    elsif b_result
      puts "next: splitting b"
      bisect(first_half(b), second_half(b), &block)
    else # bloth a_result and b_result are falsey
      puts "done: both sets are falsey"
      [a, b]
    end
  end
  
  def first_half(list)
    list[0..(list.length/2.0).floor]
  end
  
  def second_half(list)
    list[(list.length/2.0).ceil..-1]
  end
  
  extend self
end

class GlobalStateSpecs
  include ListBisector
  
  def initialize(spec_path, seed: nil, files: nil)
    @spec_path = spec_path
    @seed = seed
    @files = files # build list of all files?
  end
  
  def narrow_list
    bisect(first_half(@files), second_half(@files)) do |files|
      ap "considering #{files.length} files"
      
      cmd = command(files)
      puts "==========="
      puts cmd
      puts "==========="
      result = system(cmd)

      prompt
    end
  end
  
  def command(files)
    "./bin/bundle exec rspec --format=documentation --seed #{@seed} #{files.join(" ")} #{@spec_path}"
  end
  
  def prompt
    puts
    puts "(i)nteresting (u)nintersting"
    response = STDIN.getch
    if response == "i"
      true
    elsif response == "u"
      false
    else
      "#{response} is not understood, try again"
      prompt
    end
  end
end

files = File.read("files.txt").lines.map(&:chomp)

spec_path = "spec/models/deferred_request_spec.rb"
puts GlobalStateSpecs.new(spec_path, seed: 39246, files: files).narrow_list