Sanity Check attr_reader vs. attr_accessor -- Ruby

sanity_check.rb

class SanityCheck
  attr_reader :locked
  attr_accessor :implicit_lock

  def initialize
      puts "initialize"
    @locked = true
    @implicit_lock = false
    puts "init: #{inspect}"
  end

  def check_implicit
      puts "implicit"
    locked = !locked
    implicit_lock = !implicit_lock
    puts inspect
  end

  def check_mixed
      puts "mixed"
    @locked = !locked
    @implicit_lock = !implicit_lock
    puts inspect
  end
  
  def check_mixed_reversed
    puts "mixed reversed"
    locked = !@locked
    implicit_lock = !@implicit_lock
    puts inspect
  end

  def check_at_symbols
      puts "symbols"
    @locked = !@locked
    @implicit_lock = !@implicit_lock
    puts inspect
  end
end

puts "Each lock should toggle back and forth from test to test..."
puts "well not really...."
boom = SanityCheck.new

boom.check_implicit
boom.check_mixed
boom.check_mixed_reversed
boom.check_at_symbols