I want to get know the initialize process of rspec

rspec.rb

# the following snippt is script registered into command

#! ruby
#
# This file was generated by RubyGems.
#
# The application 'rspec-core' is installed as part of a gem, and
# this file is here to facilitate running it.
#

require 'rubygems'

version = ">= 0"

if ARGV.first
  str = ARGV.first
  str = str.dup.force_encoding("BINARY") if str.respond_to? :force_encoding
  if str =~ /\A_(.*)_\z/
    version = $1
    ARGV.shift
  end
end

gem 'rspec-core', version
# bin_path ? what is it?
load Gem.bin_path('rspec-core', 'rspec', version)

###################### rubygem handle the depandency ################

  ##
  # Find the full path to the executable for gem +name+.  If the +exec_name+
  # is not given, the gem's default_executable is chosen, otherwise the
  # specified executable's path is returned.  +requirements+ allows
  # you to specify specific gem versions.

  def self.bin_path(name, exec_name = nil, *requirements)
    # TODO: fails test_self_bin_path_bin_file_gone_in_latest
    # Gem::Specification.find_by_name(name, *requirements).bin_file exec_name

    raise ArgumentError, "you must supply exec_name" unless exec_name

    requirements = Gem::Requirement.default if
      requirements.empty?
    # new depency
    specs = Gem::Dependency.new(name, requirements).matching_specs(true)

    raise Gem::GemNotFoundException,
          "can't find gem #{name} (#{requirements})" if specs.empty?

    specs = specs.find_all { |spec|
      spec.executables.include? exec_name
    } if exec_name

    unless spec = specs.last
      msg = "can't find gem #{name} (#{requirements}) with executable #{exec_name}"
      raise Gem::GemNotFoundException, msg
    end

    spec.bin_file exec_name
  end