private method refactor

.ruby-version

1.9.3-p385

README.md

= Private Method Refactor

From a discussion on rubyparley.

path_support.rb

##
#
# Gem::PathSupport facilitates the GEM_HOME and GEM_PATH environment settings
# to the rest of RubyGems.
#
class Gem::PathSupport
  ##
  # The default system path for managing Gems.
  attr_reader :home

  ##
  # Array of paths to search for Gems.
  attr_reader :path

  ##
  #
  # Constructor. Takes a single argument which is to be treated like a
  # hashtable, or defaults to ENV, the system environment.
  #
  def initialize(env=ENV)
    @env = env
    @home = calculate_home
    @path = calculate_path
  end

  ##
  # Determine the Gem home directory (as reported by Gem.dir).

  def calculate_home
    # note 'env' vs 'ENV'...
    home = @env["GEM_HOME"] || ENV["GEM_HOME"] || Gem.default_dir
    home.gsub!(File::ALT_SEPARATOR, File::SEPARATOR) if File::ALT_SEPARATOR
    home
  end

  ##
  # Determine the Gem search path (as reported by Gem.path).

  def calculate_path
    # FIX: it should be [home, *path], not [*path, home]

    gem_path = []

    # FIX: I can't tell wtf this is doing.
    gpaths = @env["GEM_PATH"] || ENV["GEM_PATH"]
    gpaths ||= (ENV['GEM_PATH'] || "").empty? ? nil : ENV["GEM_PATH"]

    if gpaths
      if gpaths.kind_of?(Array)
        gem_path = gpaths.dup
      else
        gem_path = gpaths.split(Gem.path_separator)
      end

      if File::ALT_SEPARATOR then
        gem_path.map! do |this_path|
          this_path.gsub File::ALT_SEPARATOR, File::SEPARATOR
        end
      end

      gem_path << @home
    else
      gem_path = Gem.default_path + [@home]

      if defined?(APPLE_GEM_HOME)
        gem_path << APPLE_GEM_HOME
      end
    end

    gem_path.uniq
  end
end

test_gem_path_support.rb

require 'test/unit'

require 'fileutils'
require 'tmpdir'

require File.dirname(__FILE__) + '/path_support'

class TestGemPathSupport < Test::Unit::TestCase
  def setup
    @tempdir = Dir.mktmpdir

    ENV["GEM_HOME"] = @tempdir
    ENV["GEM_PATH"] = [@tempdir, "something"].join(File::PATH_SEPARATOR)
  end

  def teardown
    FileUtils.remove_entry_secure @tempdir
    super
  end

  def test_initialize
    ps = Gem::PathSupport.new

    assert_equal ENV["GEM_HOME"], ps.home

    expected = util_path
    assert_equal expected, ps.path, "defaults to GEM_PATH"
  end

  def test_initialize_home
    ps = Gem::PathSupport.new "GEM_HOME" => "#{@tempdir}/foo"

    assert_equal File.join(@tempdir, "foo"), ps.home

    expected = util_path + [File.join(@tempdir, 'foo')]
    assert_equal expected, ps.path
  end

  if defined?(File::ALT_SEPARATOR) and File::ALT_SEPARATOR
    def test_initialize_home_normalize
      alternate = @tempdir.gsub(File::SEPARATOR, File::ALT_SEPARATOR)
      ps = Gem::PathSupport.new "GEM_HOME" => alternate

      assert_equal @tempdir, ps.home, "normalize values"
    end
  end

  def test_initialize_path
    ps = Gem::PathSupport.new "GEM_PATH" => %W[#{@tempdir}/foo #{@tempdir}/bar]

    assert_equal ENV["GEM_HOME"], ps.home

    expected = [
                File.join(@tempdir, 'foo'),
                File.join(@tempdir, 'bar'),
                ENV["GEM_HOME"],
               ]

    assert_equal expected, ps.path
  end

  def test_initialize_home_path
    ps = Gem::PathSupport.new("GEM_HOME" => "#{@tempdir}/foo",
                              "GEM_PATH" => %W[#{@tempdir}/foo #{@tempdir}/bar])

    assert_equal File.join(@tempdir, "foo"), ps.home

    expected = [File.join(@tempdir, 'foo'), File.join(@tempdir, 'bar')]
    assert_equal expected, ps.path
  end

  def util_path
    ENV["GEM_PATH"].split(File::PATH_SEPARATOR)
  end
end