Gem::PathSupport facilitates the GEM_HOME and GEM_PATH environment settings to the rest of RubyGems.

Methods
H
N
P
Attributes
[R] home

The default system path for managing Gems.
[R] path

Array of paths to search for Gems.
Class Public methods
new(env=ENV)

Constructor. Takes a single argument which is to be treated like a hashtable, or defaults to ENV, the system environment.

Source: show | on GitHub 

# File ../ruby/lib/rubygems/path_support.rb, line 19
def initialize(env=ENV)
  @env = env

  # note 'env' vs 'ENV'...
  @home     = env["GEM_HOME"] || ENV["GEM_HOME"] || Gem.default_dir

  if File::ALT_SEPARATOR then
    @home   = @home.gsub(File::ALT_SEPARATOR, File::SEPARATOR)
  end

  self.path = env["GEM_PATH"] || ENV["GEM_PATH"]
end
Instance Private methods
home=(home)

Set the Gem home directory (as reported by Gem.dir).

Source: show | on GitHub 

# File ../ruby/lib/rubygems/path_support.rb, line 37
def home=(home)
  @home = home.to_s
end
path=(gpaths)

Set the Gem search path (as reported by Gem.path).

Source: show | on GitHub 

# File ../ruby/lib/rubygems/path_support.rb, line 44
def path=(gpaths)
  gem_path = [@home]

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

  if gpaths then
    if gpaths.kind_of?(Array) then
      gem_path.push(*gpaths)
    else
      gem_path.push(*gpaths.split(File::PATH_SEPARATOR))
    end

    if File::ALT_SEPARATOR then
      gem_path.map! do |this_path|
        this_path.gsub File::ALT_SEPARATOR, File::SEPARATOR
      end
    end
  else
    gem_path.push(*Gem.default_path)

    gem_path << APPLE_GEM_HOME if defined?(APPLE_GEM_HOME)
  end

  @path = gem_path.uniq
end