Merge RubyGems 3.2.25 and Bundler 2.2.25

138 files changed, 2534 insertions, 300 deletions

diff --git a/test/rubygems/data/null-type.gemspec.rz b/test/rubygems/data/null-type.gemspec.rz
index bad99289d1..2134fcde29 100644
--- a/test/rubygems/data/null-type.gemspec.rz
+++ b/test/rubygems/data/null-type.gemspec.rz
diff --git a/test/rubygems/helper.rb b/test/rubygems/helper.rb
new file mode 100644
index 0000000000..c3befb535f
--- /dev/null
+++ b/test/rubygems/helper.rb
@@ -0,0 +1,1603 @@
+# frozen_string_literal: true
+
+require 'rubygems'
+
+# If bundler gemspec exists, add to stubs
+bundler_gemspec = File.expand_path("../../../bundler/bundler.gemspec", __FILE__)
+if File.exist?(bundler_gemspec)
+  Gem::Specification.dirs.unshift File.dirname(bundler_gemspec)
+  Gem::Specification.class_variable_set :@@stubs, nil
+  Gem::Specification.stubs
+  Gem::Specification.dirs.shift
+end
+
+begin
+  gem 'test-unit', '~> 3.0'
+rescue Gem::LoadError
+end
+
+begin
+  require 'simplecov'
+  SimpleCov.start do
+    add_filter "/test/"
+    add_filter "/bundler/"
+    add_filter "/lib/rubygems/resolver/molinillo"
+  end
+rescue LoadError
+end
+
+if File.exist?(bundler_gemspec)
+  require_relative '../../bundler/lib/bundler'
+else
+  require 'bundler'
+end
+
+require 'test/unit'
+
+ENV["JARS_SKIP"] = "true" if Gem.java_platform? # avoid unnecessary and noisy `jar-dependencies` post install hook
+
+require 'rubygems/deprecate'
+
+require 'fileutils'
+require 'pathname'
+require 'pp'
+require 'rubygems/package'
+require 'shellwords'
+require 'tmpdir'
+require 'uri'
+require 'zlib'
+require 'benchmark' # stdlib
+require 'rubygems/mock_gem_ui'
+
+module Gem
+
+  ##
+  # Allows setting the gem path searcher.
+
+  def self.searcher=(searcher)
+    @searcher = searcher
+  end
+
+  ##
+  # Allows toggling Windows behavior.
+
+  def self.win_platform=(val)
+    @@win_platform = val
+  end
+
+  ##
+  # Allows setting path to Ruby.
+
+  def self.ruby=(ruby)
+    @ruby = ruby
+  end
+
+  ##
+  # Sets the default user interaction to a MockGemUi.
+
+  module DefaultUserInteraction
+    @ui = Gem::MockGemUi.new
+  end
+end
+
+require "rubygems/command"
+
+class Gem::Command
+  ##
+  # Allows resetting the hash of specific args per command.
+
+  def self.specific_extra_args_hash=(value)
+    @specific_extra_args_hash = value
+  end
+end
+
+##
+# RubyGemTestCase provides a variety of methods for testing rubygems and
+# gem-related behavior in a sandbox.  Through RubyGemTestCase you can install
+# and uninstall gems, fetch remote gems through a stub fetcher and be assured
+# your normal set of gems is not affected.
+
+class Gem::TestCase < Test::Unit::TestCase
+  extend Gem::Deprecate
+
+  attr_accessor :fetcher # :nodoc:
+
+  attr_accessor :gem_repo # :nodoc:
+
+  attr_accessor :uri # :nodoc:
+
+  def assert_activate(expected, *specs)
+    specs.each do |spec|
+      case spec
+      when String then
+        Gem::Specification.find_by_name(spec).activate
+      when Gem::Specification then
+        spec.activate
+      else
+        flunk spec.inspect
+      end
+    end
+
+    loaded = Gem.loaded_specs.values.map(&:full_name)
+
+    assert_equal expected.sort, loaded.sort if expected
+  end
+
+  def assert_directory_exists(path, msg = nil)
+    msg = build_message(msg, "Expected path '#{path}' to be a directory")
+    assert_path_exist path
+    assert File.directory?(path), msg
+  end
+
+  # https://github.com/seattlerb/minitest/blob/21d9e804b63c619f602f3f4ece6c71b48974707a/lib/minitest/assertions.rb#L188
+  def _synchronize
+    yield
+  end
+
+  # https://github.com/seattlerb/minitest/blob/21d9e804b63c619f602f3f4ece6c71b48974707a/lib/minitest/assertions.rb#L546
+  def capture_subprocess_io
+    _synchronize do
+      begin
+        require "tempfile"
+
+        captured_stdout, captured_stderr = Tempfile.new("out"), Tempfile.new("err")
+
+        orig_stdout, orig_stderr = $stdout.dup, $stderr.dup
+        $stdout.reopen captured_stdout
+        $stderr.reopen captured_stderr
+
+        yield
+
+        $stdout.rewind
+        $stderr.rewind
+
+        return captured_stdout.read, captured_stderr.read
+      ensure
+        captured_stdout.unlink
+        captured_stderr.unlink
+        $stdout.reopen orig_stdout
+        $stderr.reopen orig_stderr
+
+        orig_stdout.close
+        orig_stderr.close
+        captured_stdout.close
+        captured_stderr.close
+      end
+    end
+  end
+
+  ##
+  # Sets the ENABLE_SHARED entry in RbConfig::CONFIG to +value+ and restores
+  # the original value when the block ends
+
+  def enable_shared(value)
+    enable_shared = RbConfig::CONFIG['ENABLE_SHARED']
+    RbConfig::CONFIG['ENABLE_SHARED'] = value
+
+    yield
+  ensure
+    if enable_shared
+      RbConfig::CONFIG['enable_shared'] = enable_shared
+    else
+      RbConfig::CONFIG.delete 'enable_shared'
+    end
+  end
+
+  ##
+  # Sets the vendordir entry in RbConfig::CONFIG to +value+ and restores the
+  # original value when the block ends
+  #
+  def vendordir(value)
+    vendordir = RbConfig::CONFIG['vendordir']
+
+    if value
+      RbConfig::CONFIG['vendordir'] = value
+    else
+      RbConfig::CONFIG.delete 'vendordir'
+    end
+
+    yield
+  ensure
+    if vendordir
+      RbConfig::CONFIG['vendordir'] = vendordir
+    else
+      RbConfig::CONFIG.delete 'vendordir'
+    end
+  end
+
+  ##
+  # Sets the bindir entry in RbConfig::CONFIG to +value+ and restores the
+  # original value when the block ends
+  #
+  def bindir(value)
+    with_clean_path_to_ruby do
+      bindir = RbConfig::CONFIG['bindir']
+
+      if value
+        RbConfig::CONFIG['bindir'] = value
+      else
+        RbConfig::CONFIG.delete 'bindir'
+      end
+
+      begin
+        yield
+      ensure
+        if bindir
+          RbConfig::CONFIG['bindir'] = bindir
+        else
+          RbConfig::CONFIG.delete 'bindir'
+        end
+      end
+    end
+  end
+
+  ##
+  # Sets the EXEEXT entry in RbConfig::CONFIG to +value+ and restores the
+  # original value when the block ends
+  #
+  def exeext(value)
+    exeext = RbConfig::CONFIG['EXEEXT']
+
+    if value
+      RbConfig::CONFIG['EXEEXT'] = value
+    else
+      RbConfig::CONFIG.delete 'EXEEXT'
+    end
+
+    yield
+  ensure
+    if exeext
+      RbConfig::CONFIG['EXEEXT'] = exeext
+    else
+      RbConfig::CONFIG.delete 'EXEEXT'
+    end
+  end
+
+  def scan_make_command_lines(output)
+    output.scan(/^#{Regexp.escape make_command}(?:[[:blank:]].*)?$/)
+  end
+
+  def parse_make_command_line(line)
+    command, *args = line.shellsplit
+
+    targets = []
+    macros = {}
+
+    args.each do |arg|
+      case arg
+      when /\A(\w+)=/
+        macros[$1] = $'
+      else
+        targets << arg
+      end
+    end
+
+    targets << '' if targets.empty?
+
+    {
+      :command => command,
+      :targets => targets,
+      :macros => macros,
+    }
+  end
+
+  def assert_contains_make_command(target, output, msg = nil)
+    if output.match(/\n/)
+      msg = build_message(msg,
+        "Expected output containing make command \"%s\", but was \n\nBEGIN_OF_OUTPUT\n%sEND_OF_OUTPUT" % [
+          ('%s %s' % [make_command, target]).rstrip,
+          output,
+        ]
+      )
+    else
+      msg = build_message(msg,
+        'Expected make command "%s": %s' % [
+          ('%s %s' % [make_command, target]).rstrip,
+          output,
+        ]
+      )
+    end
+
+    assert scan_make_command_lines(output).any? {|line|
+      make = parse_make_command_line(line)
+
+      if make[:targets].include?(target)
+        yield make, line if block_given?
+        true
+      else
+        false
+      end
+    }, msg
+  end
+
+  include Gem::DefaultUserInteraction
+
+  ##
+  # #setup prepares a sandboxed location to install gems.  All installs are
+  # directed to a temporary directory.  All install plugins are removed.
+  #
+  # If the +RUBY+ environment variable is set the given path is used for
+  # Gem::ruby.  The local platform is set to <tt>i386-mswin32</tt> for Windows
+  # or <tt>i686-darwin8.10.1</tt> otherwise.
+
+  def setup
+    @orig_env = ENV.to_hash
+    @tmp = File.expand_path("tmp")
+
+    FileUtils.mkdir_p @tmp
+
+    ENV['GEM_VENDOR'] = nil
+    ENV['GEMRC'] = nil
+    ENV['XDG_CACHE_HOME'] = nil
+    ENV['XDG_CONFIG_HOME'] = nil
+    ENV['XDG_DATA_HOME'] = nil
+    ENV['SOURCE_DATE_EPOCH'] = nil
+    ENV['BUNDLER_VERSION'] = nil
+
+    @current_dir = Dir.pwd
+    @fetcher     = nil
+
+    @back_ui                       = Gem::DefaultUserInteraction.ui
+    @ui                            = Gem::MockGemUi.new
+    # This needs to be a new instance since we call use_ui(@ui) when we want to
+    # capture output
+    Gem::DefaultUserInteraction.ui = Gem::MockGemUi.new
+
+    @tempdir = Dir.mktmpdir("test_rubygems_", @tmp)
+    @tempdir.tap(&Gem::UNTAINT)
+
+    ENV["TMPDIR"] = @tempdir
+
+    @orig_SYSTEM_WIDE_CONFIG_FILE = Gem::ConfigFile::SYSTEM_WIDE_CONFIG_FILE
+    Gem::ConfigFile.send :remove_const, :SYSTEM_WIDE_CONFIG_FILE
+    Gem::ConfigFile.send :const_set, :SYSTEM_WIDE_CONFIG_FILE,
+                         File.join(@tempdir, 'system-gemrc')
+
+    @gemhome  = File.join @tempdir, 'gemhome'
+    @userhome = File.join @tempdir, 'userhome'
+    ENV["GEM_SPEC_CACHE"] = File.join @tempdir, 'spec_cache'
+
+    @orig_ruby = if ENV['RUBY']
+                   ruby = Gem.ruby
+                   Gem.ruby = ENV['RUBY']
+                   ruby
+                 end
+
+    @git = ENV['GIT'] || (win_platform? ? 'git.exe' : 'git')
+
+    Gem.ensure_gem_subdirectories @gemhome
+    Gem.ensure_default_gem_subdirectories @gemhome
+
+    @orig_LOAD_PATH = $LOAD_PATH.dup
+    $LOAD_PATH.map! do |s|
+      expand_path = File.realpath(s) rescue File.expand_path(s)
+      if expand_path != s
+        expand_path.tap(&Gem::UNTAINT)
+        if s.instance_variable_defined?(:@gem_prelude_index)
+          expand_path.instance_variable_set(:@gem_prelude_index, expand_path)
+        end
+        expand_path.freeze if s.frozen?
+        s = expand_path
+      end
+      s
+    end
+
+    Dir.chdir @tempdir
+
+    ENV['HOME'] = @userhome
+    Gem.instance_variable_set :@config_file, nil
+    Gem.instance_variable_set :@user_home, nil
+    Gem.instance_variable_set :@config_home, nil
+    Gem.instance_variable_set :@data_home, nil
+    Gem.instance_variable_set :@gemdeps, nil
+    Gem.instance_variable_set :@env_requirements_by_name, nil
+    Gem.send :remove_instance_variable, :@ruby_version if
+      Gem.instance_variables.include? :@ruby_version
+
+    FileUtils.mkdir_p @userhome
+
+    ENV['GEM_PRIVATE_KEY_PASSPHRASE'] = PRIVATE_KEY_PASSPHRASE
+
+    if Gem.java_platform?
+      @orig_default_gem_home = RbConfig::CONFIG['default_gem_home']
+      RbConfig::CONFIG['default_gem_home'] = @gemhome
+    else
+      Gem.instance_variable_set(:@default_dir, @gemhome)
+    end
+
+    @orig_bindir = RbConfig::CONFIG["bindir"]
+    RbConfig::CONFIG["bindir"] = File.join @gemhome, "bin"
+
+    Gem::Specification.unresolved_deps.clear
+    Gem.use_paths(@gemhome)
+
+    Gem.loaded_specs.clear
+    Gem.instance_variable_set(:@activated_gem_paths, 0)
+    Gem.clear_default_specs
+    Bundler.reset!
+
+    Gem.configuration.verbose = true
+    Gem.configuration.update_sources = true
+
+    Gem::RemoteFetcher.fetcher = Gem::FakeFetcher.new
+
+    @gem_repo = "http://gems.example.com/"
+    @uri = URI.parse @gem_repo
+    Gem.sources.replace [@gem_repo]
+
+    Gem.searcher = nil
+    Gem::SpecFetcher.fetcher = nil
+
+    @orig_arch = RbConfig::CONFIG['arch']
+
+    if win_platform?
+      util_set_arch 'i386-mswin32'
+    else
+      util_set_arch 'i686-darwin8.10.1'
+    end
+
+    @orig_hooks = {}
+    %w[post_install_hooks done_installing_hooks post_uninstall_hooks pre_uninstall_hooks pre_install_hooks pre_reset_hooks post_reset_hooks post_build_hooks].each do |name|
+      @orig_hooks[name] = Gem.send(name).dup
+    end
+
+    @marshal_version = "#{Marshal::MAJOR_VERSION}.#{Marshal::MINOR_VERSION}"
+    @orig_LOADED_FEATURES = $LOADED_FEATURES.dup
+  end
+
+  ##
+  # #teardown restores the process to its original state and removes the
+  # tempdir
+
+  def teardown
+    $LOAD_PATH.replace @orig_LOAD_PATH if @orig_LOAD_PATH
+    if @orig_LOADED_FEATURES
+      if @orig_LOAD_PATH
+        ($LOADED_FEATURES - @orig_LOADED_FEATURES).each do |feat|
+          $LOADED_FEATURES.delete(feat) if feat.start_with?(@tmp)
+        end
+      else
+        $LOADED_FEATURES.replace @orig_LOADED_FEATURES
+      end
+    end
+
+    RbConfig::CONFIG['arch'] = @orig_arch
+
+    if defined? Gem::RemoteFetcher
+      Gem::RemoteFetcher.fetcher = nil
+    end
+
+    Dir.chdir @current_dir
+
+    FileUtils.rm_rf @tempdir
+
+    ENV.replace(@orig_env)
+
+    Gem::ConfigFile.send :remove_const, :SYSTEM_WIDE_CONFIG_FILE
+    Gem::ConfigFile.send :const_set, :SYSTEM_WIDE_CONFIG_FILE,
+                         @orig_SYSTEM_WIDE_CONFIG_FILE
+
+    Gem.ruby = @orig_ruby if @orig_ruby
+
+    RbConfig::CONFIG['bindir'] = @orig_bindir
+
+    if Gem.java_platform?
+      RbConfig::CONFIG['default_gem_home'] = @orig_default_gem_home
+    else
+      Gem.instance_variable_set :@default_dir, nil
+    end
+
+    Gem::Specification._clear_load_cache
+    Gem::Specification.unresolved_deps.clear
+    Gem::refresh
+
+    @orig_hooks.each do |name, hooks|
+      Gem.send(name).replace hooks
+    end
+
+    @back_ui.close
+  end
+
+  def credential_setup
+    @temp_cred = File.join(@userhome, '.gem', 'credentials')
+    FileUtils.mkdir_p File.dirname(@temp_cred)
+    File.write @temp_cred, ':rubygems_api_key: 701229f217cdf23b1344c7b4b54ca97'
+    File.chmod 0600, @temp_cred
+  end
+
+  def credential_teardown
+    FileUtils.rm_rf @temp_cred
+  end
+
+  def common_installer_setup
+    common_installer_teardown
+
+    Gem.post_build do |installer|
+      @post_build_hook_arg = installer
+      true
+    end
+
+    Gem.post_install do |installer|
+      @post_install_hook_arg = installer
+    end
+
+    Gem.post_uninstall do |uninstaller|
+      @post_uninstall_hook_arg = uninstaller
+    end
+
+    Gem.pre_install do |installer|
+      @pre_install_hook_arg = installer
+      true
+    end
+
+    Gem.pre_uninstall do |uninstaller|
+      @pre_uninstall_hook_arg = uninstaller
+    end
+  end
+
+  def common_installer_teardown
+    Gem.post_build_hooks.clear
+    Gem.post_install_hooks.clear
+    Gem.done_installing_hooks.clear
+    Gem.post_reset_hooks.clear
+    Gem.post_uninstall_hooks.clear
+    Gem.pre_install_hooks.clear
+    Gem.pre_reset_hooks.clear
+    Gem.pre_uninstall_hooks.clear
+  end
+
+  def without_any_upwards_gemfiles
+    ENV["BUNDLE_GEMFILE"] = File.join(@tempdir, "Gemfile")
+  end
+
+  ##
+  # A git_gem is used with a gem dependencies file.  The gem created here
+  # has no files, just a gem specification for the given +name+ and +version+.
+  #
+  # Yields the +specification+ to the block, if given
+
+  def git_gem(name = 'a', version = 1)
+    have_git?
+
+    directory = File.join 'git', name
+    directory = File.expand_path directory
+
+    git_spec = Gem::Specification.new name, version do |specification|
+      yield specification if block_given?
+    end
+
+    FileUtils.mkdir_p directory
+
+    gemspec = "#{name}.gemspec"
+
+    File.open File.join(directory, gemspec), 'w' do |io|
+      io.write git_spec.to_ruby
+    end
+
+    head = nil
+
+    Dir.chdir directory do
+      unless File.exist? '.git'
+        system @git, 'init', '--quiet'
+        system @git, 'config', 'user.name',  'RubyGems Tests'
+        system @git, 'config', 'user.email', 'rubygems@example'
+      end
+
+      system @git, 'add', gemspec
+      system @git, 'commit', '-a', '-m', 'a non-empty commit message', '--quiet'
+      head = Gem::Util.popen(@git, 'rev-parse', 'master').strip
+    end
+
+    return name, git_spec.version, directory, head
+  end
+
+  ##
+  # Skips this test unless you have a git executable
+
+  def have_git?
+    return if in_path? @git
+
+    skip 'cannot find git executable, use GIT environment variable to set'
+  end
+
+  def in_path?(executable) # :nodoc:
+    return true if %r{\A([A-Z]:|/)} =~ executable and File.exist? executable
+
+    ENV['PATH'].split(File::PATH_SEPARATOR).any? do |directory|
+      File.exist? File.join directory, executable
+    end
+  end
+
+  ##
+  # Builds and installs the Gem::Specification +spec+
+
+  def install_gem(spec, options = {})
+    require 'rubygems/installer'
+
+    gem = spec.cache_file
+
+    unless File.exist? gem
+      use_ui Gem::MockGemUi.new do
+        Dir.chdir @tempdir do
+          Gem::Package.build spec
+        end
+      end
+
+      gem = File.join(@tempdir, File.basename(gem)).tap(&Gem::UNTAINT)
+    end
+
+    Gem::Installer.at(gem, options.merge({:wrappers => true})).install
+  end
+
+  ##
+  # Builds and installs the Gem::Specification +spec+ into the user dir
+
+  def install_gem_user(spec)
+    install_gem spec, :user_install => true
+  end
+
+  ##
+  # Uninstalls the Gem::Specification +spec+
+  def uninstall_gem(spec)
+    require 'rubygems/uninstaller'
+
+    Class.new(Gem::Uninstaller) do
+      def ask_if_ok(spec)
+        true
+      end
+    end.new(spec.name, :executables => true, :user_install => true).uninstall
+  end
+
+  ##
+  # Enables pretty-print for all tests
+
+  def mu_pp(obj)
+    s = String.new
+    s = PP.pp obj, s
+    s = s.force_encoding(Encoding.default_external)
+    s.chomp
+  end
+
+  ##
+  # Reads a Marshal file at +path+
+
+  def read_cache(path)
+    File.open path.dup.tap(&Gem::UNTAINT), 'rb' do |io|
+      Marshal.load io.read
+    end
+  end
+
+  ##
+  # Reads a binary file at +path+
+
+  def read_binary(path)
+    Gem.read_binary path
+  end
+
+  ##
+  # Writes a binary file to +path+ which is relative to +@gemhome+
+
+  def write_file(path)
+    path = File.join @gemhome, path unless Pathname.new(path).absolute?
+    dir = File.dirname path
+    FileUtils.mkdir_p dir unless File.directory? dir
+
+    File.open path, 'wb' do |io|
+      yield io if block_given?
+    end
+
+    path
+  end
+
+  ##
+  # Load a YAML string, the psych 3 way
+
+  def load_yaml(yaml)
+    if YAML.respond_to?(:unsafe_load)
+      YAML.unsafe_load(yaml)
+    else
+      YAML.load(yaml)
+    end
+  end
+
+  ##
+  # Load a YAML file, the psych 3 way
+
+  def load_yaml_file(file)
+    if YAML.respond_to?(:unsafe_load_file)
+      YAML.unsafe_load_file(file)
+    else
+      YAML.load_file(file)
+    end
+  end
+
+  def all_spec_names
+    Gem::Specification.map(&:full_name)
+  end
+
+  ##
+  # Creates a Gem::Specification with a minimum of extra work.  +name+ and
+  # +version+ are the gem's name and version,  platform, author, email,
+  # homepage, summary and description are defaulted.  The specification is
+  # yielded for customization.
+  #
+  # The gem is added to the installed gems in +@gemhome+ and the runtime.
+  #
+  # Use this with #write_file to build an installed gem.
+
+  def quick_gem(name, version='2')
+    require 'rubygems/specification'
+
+    spec = Gem::Specification.new do |s|
+      s.platform    = Gem::Platform::RUBY
+      s.name        = name
+      s.version     = version
+      s.author      = 'A User'
+      s.email       = 'example@example.com'
+      s.homepage    = 'http://example.com'
+      s.summary     = "this is a summary"
+      s.description = "This is a test description"
+
+      yield(s) if block_given?
+    end
+
+    written_path = write_file spec.spec_file do |io|
+      io.write spec.to_ruby_for_cache
+    end
+
+    spec.loaded_from = written_path
+
+    Gem::Specification.reset
+
+    return spec
+  end
+
+  ##
+  # Builds a gem from +spec+ and places it in <tt>File.join @gemhome,
+  # 'cache'</tt>.  Automatically creates files based on +spec.files+
+
+  def util_build_gem(spec)
+    dir = spec.gem_dir
+    FileUtils.mkdir_p dir
+
+    Dir.chdir dir do
+      spec.files.each do |file|
+        next if File.exist? file
+        FileUtils.mkdir_p File.dirname(file)
+
+        File.open file, 'w' do |fp|
+          fp.puts "# #{file}"
+        end
+      end
+
+      use_ui Gem::MockGemUi.new do
+        Gem::Package.build spec
+      end
+
+      cache = spec.cache_file
+      FileUtils.mv File.basename(cache), cache
+    end
+  end
+
+  def util_remove_gem(spec)
+    FileUtils.rm_rf spec.cache_file
+    FileUtils.rm_rf spec.spec_file
+  end
+
+  ##
+  # Removes all installed gems from +@gemhome+.
+
+  def util_clear_gems
+    FileUtils.rm_rf File.join(@gemhome, "gems")
+    FileUtils.mkdir File.join(@gemhome, "gems")
+    FileUtils.rm_rf File.join(@gemhome, "specifications")
+    FileUtils.mkdir File.join(@gemhome, "specifications")
+    Gem::Specification.reset
+  end
+
+  ##
+  # Install the provided specs
+
+  def install_specs(*specs)
+    specs.each do |spec|
+      Gem::Installer.for_spec(spec, :force => true).install
+    end
+
+    Gem.searcher = nil
+  end
+
+  ##
+  # Installs the provided default specs including writing the spec file
+
+  def install_default_gems(*specs)
+    specs.each do |spec|
+      installer = Gem::Installer.for_spec(spec, :install_as_default => true)
+      installer.install
+      Gem.register_default_spec(spec)
+    end
+  end
+
+  def loaded_spec_names
+    Gem.loaded_specs.values.map(&:full_name).sort
+  end
+
+  def unresolved_names
+    Gem::Specification.unresolved_deps.values.map(&:to_s).sort
+  end
+
+  def save_loaded_features
+    old_loaded_features = $LOADED_FEATURES.dup
+    yield
+  ensure
+    prefix = File.dirname(__FILE__) + "/"
+    new_features = ($LOADED_FEATURES - old_loaded_features)
+    old_loaded_features.concat(new_features.select {|f| f.rindex(prefix, 0) })
+    $LOADED_FEATURES.replace old_loaded_features
+  end
+
+  def new_default_spec(name, version, deps = nil, *files)
+    spec = util_spec name, version, deps
+
+    spec.loaded_from = File.join(@gemhome, "specifications", "default", spec.spec_name)
+    spec.files = files
+
+    lib_dir = File.join(@tempdir, "default_gems", "lib")
+    lib_dir.instance_variable_set(:@gem_prelude_index, lib_dir)
+    Gem.instance_variable_set(:@default_gem_load_paths, [*Gem.send(:default_gem_load_paths), lib_dir])
+    $LOAD_PATH.unshift(lib_dir)
+    files.each do |file|
+      rb_path = File.join(lib_dir, file)
+      FileUtils.mkdir_p(File.dirname(rb_path))
+      File.open(rb_path, "w") do |rb|
+        rb << "# #{file}"
+      end
+    end
+
+    spec
+  end
+
+  ##
+  # Creates a spec with +name+, +version+.  +deps+ can specify the dependency
+  # or a +block+ can be given for full customization of the specification.
+
+  def util_spec(name, version = 2, deps = nil, *files) # :yields: specification
+    raise "deps or block, not both" if deps and block_given?
+
+    spec = Gem::Specification.new do |s|
+      s.platform    = Gem::Platform::RUBY
+      s.name        = name
+      s.version     = version
+      s.author      = 'A User'
+      s.email       = 'example@example.com'
+      s.homepage    = 'http://example.com'
+      s.summary     = "this is a summary"
+      s.description = "This is a test description"
+
+      s.files.push(*files) unless files.empty?
+
+      yield s if block_given?
+    end
+
+    if deps
+      deps.keys.each do |n|
+        spec.add_dependency n, (deps[n] || '>= 0')
+      end
+    end
+
+    unless files.empty?
+      write_file spec.spec_file do |io|
+        io.write spec.to_ruby_for_cache
+      end
+
+      util_build_gem spec
+
+      FileUtils.rm spec.spec_file
+    end
+
+    return spec
+  end
+
+  ##
+  # Creates a gem with +name+, +version+ and +deps+.  The specification will
+  # be yielded before gem creation for customization.  The gem will be placed
+  # in <tt>File.join @tempdir, 'gems'</tt>.  The specification and .gem file
+  # location are returned.
+
+  def util_gem(name, version, deps = nil, &block)
+    if deps
+      block = proc do |s|
+        deps.keys.each do |n|
+          s.add_dependency n, (deps[n] || '>= 0')
+        end
+      end
+    end
+
+    spec = quick_gem(name, version, &block)
+
+    util_build_gem spec
+
+    cache_file = File.join @tempdir, 'gems', "#{spec.original_name}.gem"
+    FileUtils.mkdir_p File.dirname cache_file
+    FileUtils.mv spec.cache_file, cache_file
+    FileUtils.rm spec.spec_file
+
+    spec.loaded_from = nil
+
+    [spec, cache_file]
+  end
+
+  ##
+  # Gzips +data+.
+
+  def util_gzip(data)
+    out = StringIO.new
+
+    Zlib::GzipWriter.wrap out do |io|
+      io.write data
+    end
+
+    out.string
+  end
+
+  ##
+  # Creates several default gems which all have a lib/code.rb file.  The gems
+  # are not installed but are available in the cache dir.
+  #
+  # +@a1+:: gem a version 1, this is the best-described gem.
+  # +@a2+:: gem a version 2
+  # +@a3a:: gem a version 3.a
+  # +@a_evil9+:: gem a_evil version 9, use this to ensure similarly-named gems
+  #              don't collide with a.
+  # +@b2+:: gem b version 2
+  # +@c1_2+:: gem c version 1.2
+  # +@pl1+:: gem pl version 1, this gem has a legacy platform of i386-linux.
+  #
+  # Additional +prerelease+ gems may also be created:
+  #
+  # +@a2_pre+:: gem a version 2.a
+  # TODO: nuke this and fix tests. this should speed up a lot
+
+  def util_make_gems(prerelease = false)
+    @a1 = quick_gem 'a', '1' do |s|
+      s.files = %w[lib/code.rb]
+      s.require_paths = %w[lib]
+      s.date = Gem::Specification::TODAY - 86400
+      s.homepage = 'http://a.example.com'
+      s.email = %w[example@example.com example2@example.com]
+      s.authors = %w[Example Example2]
+      s.description = <<-DESC
+This line is really, really long.  So long, in fact, that it is more than eighty characters long!  The purpose of this line is for testing wrapping behavior because sometimes people don't wrap their text to eighty characters.  Without the wrapping, the text might not look good in the RSS feed.
+
+Also, a list:
+  * An entry that\'s actually kind of sort
+  * an entry that\'s really long, which will probably get wrapped funny.  That's ok, somebody wasn't thinking straight when they made it more than eighty characters.
+      DESC
+    end
+
+    init = proc do |s|
+      s.files = %w[lib/code.rb]
+      s.require_paths = %w[lib]
+    end
+
+    @a2      = quick_gem('a', '2',      &init)
+    @a3a     = quick_gem('a', '3.a',    &init)
+    @a_evil9 = quick_gem('a_evil', '9', &init)
+    @b2      = quick_gem('b', '2',      &init)
+    @c1_2    = quick_gem('c', '1.2',    &init)
+    @x       = quick_gem('x', '1',      &init)
+    @dep_x   = quick_gem('dep_x', '1') do |s|
+      s.files = %w[lib/code.rb]
+      s.require_paths = %w[lib]
+      s.add_dependency 'x', '>= 1'
+    end
+
+    @pl1 = quick_gem 'pl', '1' do |s| # l for legacy
+      s.files = %w[lib/code.rb]
+      s.require_paths = %w[lib]
+      s.platform = Gem::Platform.new 'i386-linux'
+      s.instance_variable_set :@original_platform, 'i386-linux'
+    end
+
+    if prerelease
+      @a2_pre = quick_gem('a', '2.a', &init)
+      write_file File.join(*%W[gems #{@a2_pre.original_name} lib code.rb])
+      util_build_gem @a2_pre
+    end
+
+    write_file File.join(*%W[gems #{@a1.original_name}      lib code.rb])
+    write_file File.join(*%W[gems #{@a2.original_name}      lib code.rb])
+    write_file File.join(*%W[gems #{@a3a.original_name}     lib code.rb])
+    write_file File.join(*%W[gems #{@a_evil9.original_name} lib code.rb])
+    write_file File.join(*%W[gems #{@b2.original_name}      lib code.rb])
+    write_file File.join(*%W[gems #{@c1_2.original_name}    lib code.rb])
+    write_file File.join(*%W[gems #{@pl1.original_name}     lib code.rb])
+    write_file File.join(*%W[gems #{@x.original_name}       lib code.rb])
+    write_file File.join(*%W[gems #{@dep_x.original_name}   lib code.rb])
+
+    [@a1, @a2, @a3a, @a_evil9, @b2, @c1_2, @pl1, @x, @dep_x].each do |spec|
+      util_build_gem spec
+    end
+
+    FileUtils.rm_r File.join(@gemhome, "gems", @pl1.original_name)
+  end
+
+  ##
+  # Set the platform to +arch+
+
+  def util_set_arch(arch)
+    RbConfig::CONFIG['arch'] = arch
+    platform = Gem::Platform.new arch
+
+    Gem.instance_variable_set :@platforms, nil
+    Gem::Platform.instance_variable_set :@local, nil
+
+    yield if block_given?
+
+    platform
+  end
+
+  ##
+  # Add +spec+ to +@fetcher+ serving the data in the file +path+.
+  # +repo+ indicates which repo to make +spec+ appear to be in.
+
+  def add_to_fetcher(spec, path=nil, repo=@gem_repo)
+    path ||= spec.cache_file
+    @fetcher.data["#{@gem_repo}gems/#{spec.file_name}"] = read_binary(path)
+  end
+
+  ##
+  # Sets up Gem::SpecFetcher to return information from the gems in +specs+.
+
+  def util_setup_spec_fetcher(*specs)
+    all_specs = Gem::Specification.to_a + specs
+    Gem::Specification._resort! all_specs
+
+    spec_fetcher = Gem::SpecFetcher.fetcher
+
+    prerelease, all = all_specs.partition {|spec| spec.version.prerelease? }
+    latest = Gem::Specification._latest_specs all_specs
+
+    spec_fetcher.specs[@uri] = []
+    all.each do |spec|
+      spec_fetcher.specs[@uri] << spec.name_tuple
+    end
+
+    spec_fetcher.latest_specs[@uri] = []
+    latest.each do |spec|
+      spec_fetcher.latest_specs[@uri] << spec.name_tuple
+    end
+
+    spec_fetcher.prerelease_specs[@uri] = []
+    prerelease.each do |spec|
+      spec_fetcher.prerelease_specs[@uri] << spec.name_tuple
+    end
+
+    # HACK for test_download_to_cache
+    unless Gem::RemoteFetcher === @fetcher
+      v = Gem.marshal_version
+
+      specs = all.map {|spec| spec.name_tuple }
+      s_zip = util_gzip Marshal.dump Gem::NameTuple.to_basic specs
+
+      latest_specs = latest.map do |spec|
+        spec.name_tuple
+      end
+
+      l_zip = util_gzip Marshal.dump Gem::NameTuple.to_basic latest_specs
+
+      prerelease_specs = prerelease.map {|spec| spec.name_tuple }
+      p_zip = util_gzip Marshal.dump Gem::NameTuple.to_basic prerelease_specs
+
+      @fetcher.data["#{@gem_repo}specs.#{v}.gz"]            = s_zip
+      @fetcher.data["#{@gem_repo}latest_specs.#{v}.gz"]     = l_zip
+      @fetcher.data["#{@gem_repo}prerelease_specs.#{v}.gz"] = p_zip
+
+      v = Gem.marshal_version
+
+      all_specs.each do |spec|
+        path = "#{@gem_repo}quick/Marshal.#{v}/#{spec.original_name}.gemspec.rz"
+        data = Marshal.dump spec
+        data_deflate = Zlib::Deflate.deflate data
+        @fetcher.data[path] = data_deflate
+      end
+    end
+
+    nil # force errors
+  end
+
+  ##
+  # Deflates +data+
+
+  def util_zip(data)
+    Zlib::Deflate.deflate data
+  end
+
+  def util_set_RUBY_VERSION(version, patchlevel = nil, revision = nil, description = nil, engine = "ruby", engine_version = nil)
+    if Gem.instance_variables.include? :@ruby_version
+      Gem.send :remove_instance_variable, :@ruby_version
+    end
+
+    @RUBY_VERSION        = RUBY_VERSION
+    @RUBY_PATCHLEVEL     = RUBY_PATCHLEVEL     if defined?(RUBY_PATCHLEVEL)
+    @RUBY_REVISION       = RUBY_REVISION       if defined?(RUBY_REVISION)
+    @RUBY_DESCRIPTION    = RUBY_DESCRIPTION    if defined?(RUBY_DESCRIPTION)
+    @RUBY_ENGINE         = RUBY_ENGINE
+    @RUBY_ENGINE_VERSION = RUBY_ENGINE_VERSION if defined?(RUBY_ENGINE_VERSION)
+
+    util_clear_RUBY_VERSION
+
+    Object.const_set :RUBY_VERSION,        version
+    Object.const_set :RUBY_PATCHLEVEL,     patchlevel     if patchlevel
+    Object.const_set :RUBY_REVISION,       revision       if revision
+    Object.const_set :RUBY_DESCRIPTION,    description    if description
+    Object.const_set :RUBY_ENGINE,         engine
+    Object.const_set :RUBY_ENGINE_VERSION, engine_version if engine_version
+  end
+
+  def util_restore_RUBY_VERSION
+    util_clear_RUBY_VERSION
+
+    Object.const_set :RUBY_VERSION,        @RUBY_VERSION
+    Object.const_set :RUBY_PATCHLEVEL,     @RUBY_PATCHLEVEL  if
+      defined?(@RUBY_PATCHLEVEL)
+    Object.const_set :RUBY_REVISION,       @RUBY_REVISION    if
+      defined?(@RUBY_REVISION)
+    Object.const_set :RUBY_DESCRIPTION,    @RUBY_DESCRIPTION if
+      defined?(@RUBY_DESCRIPTION)
+    Object.const_set :RUBY_ENGINE,         @RUBY_ENGINE
+    Object.const_set :RUBY_ENGINE_VERSION, @RUBY_ENGINE_VERSION if
+      defined?(@RUBY_ENGINE_VERSION)
+  end
+
+  def util_clear_RUBY_VERSION
+    Object.send :remove_const, :RUBY_VERSION
+    Object.send :remove_const, :RUBY_PATCHLEVEL     if defined?(RUBY_PATCHLEVEL)
+    Object.send :remove_const, :RUBY_REVISION       if defined?(RUBY_REVISION)
+    Object.send :remove_const, :RUBY_DESCRIPTION    if defined?(RUBY_DESCRIPTION)
+    Object.send :remove_const, :RUBY_ENGINE
+    Object.send :remove_const, :RUBY_ENGINE_VERSION if defined?(RUBY_ENGINE_VERSION)
+  end
+
+  ##
+  # Is this test being run on a Windows platform?
+
+  def self.win_platform?
+    Gem.win_platform?
+  end
+
+  ##
+  # Is this test being run on a Windows platform?
+
+  def win_platform?
+    Gem.win_platform?
+  end
+
+  ##
+  # Is this test being run on a Java platform?
+
+  def self.java_platform?
+    Gem.java_platform?
+  end
+
+  ##
+  # Is this test being run on a Java platform?
+
+  def java_platform?
+    Gem.java_platform?
+  end
+
+  ##
+  # Returns whether or not we're on a version of Ruby built with VC++ (or
+  # Borland) versus Cygwin, Mingw, etc.
+
+  def self.vc_windows?
+    RUBY_PLATFORM.match('mswin')
+  end
+
+  ##
+  # Returns whether or not we're on a version of Ruby built with VC++ (or
+  # Borland) versus Cygwin, Mingw, etc.
+
+  def vc_windows?
+    RUBY_PLATFORM.match('mswin')
+  end
+
+  ##
+  # Returns the make command for the current platform. For versions of Ruby
+  # built on MS Windows with VC++ or Borland it will return 'nmake'. On all
+  # other platforms, including Cygwin, it will return 'make'.
+
+  def self.make_command
+    ENV["make"] || ENV["MAKE"] || (vc_windows? ? 'nmake' : 'make')
+  end
+
+  ##
+  # Returns the make command for the current platform. For versions of Ruby
+  # built on MS Windows with VC++ or Borland it will return 'nmake'. On all
+  # other platforms, including Cygwin, it will return 'make'.
+
+  def make_command
+    ENV["make"] || ENV["MAKE"] || (vc_windows? ? 'nmake' : 'make')
+  end
+
+  ##
+  # Returns whether or not the nmake command could be found.
+
+  def nmake_found?
+    system('nmake /? 1>NUL 2>&1')
+  end
+
+  # In case we're building docs in a background process, this method waits for
+  # that process to exit (or if it's already been reaped, or never happened,
+  # swallows the Errno::ECHILD error).
+  def wait_for_child_process_to_exit
+    Process.wait if Process.respond_to?(:fork)
+  rescue Errno::ECHILD
+  end
+
+  ##
+  # Allows tests to use a random (but controlled) port number instead of
+  # a hardcoded one. This helps CI tools when running parallels builds on
+  # the same builder slave.
+
+  def self.process_based_port
+    @@process_based_port ||= 8000 + $$ % 1000
+  end
+
+  ##
+  # See ::process_based_port
+
+  def process_based_port
+    self.class.process_based_port
+  end
+
+  ##
+  # Allows the proper version of +rake+ to be used for the test.
+
+  def build_rake_in(good=true)
+    gem_ruby = Gem.ruby
+    Gem.ruby = self.class.rubybin
+    env_rake = ENV["rake"]
+    rake = (good ? @@good_rake : @@bad_rake)
+    ENV["rake"] = rake
+    yield rake
+  ensure
+    Gem.ruby = gem_ruby
+    if env_rake
+      ENV["rake"] = env_rake
+    else
+      ENV.delete("rake")
+    end
+  end
+
+  ##
+  # Finds the path to the Ruby executable
+
+  def self.rubybin
+    ruby = ENV["RUBY"]
+    return ruby if ruby
+    ruby = "ruby"
+    rubyexe = "#{ruby}.exe"
+
+    3.times do
+      if File.exist? ruby and File.executable? ruby and !File.directory? ruby
+        return File.expand_path(ruby)
+      end
+      if File.exist? rubyexe and File.executable? rubyexe
+        return File.expand_path(rubyexe)
+      end
+      ruby = File.join("..", ruby)
+    end
+
+    begin
+      Gem.ruby
+    rescue LoadError
+      "ruby"
+    end
+  end
+
+  def ruby_with_rubygems_in_load_path
+    [Gem.ruby, "-I", File.expand_path("../../lib", __dir__)]
+  end
+
+  def with_clean_path_to_ruby
+    orig_ruby = Gem.ruby
+
+    Gem.instance_variable_set :@ruby, nil
+
+    yield
+  ensure
+    Gem.instance_variable_set :@ruby, orig_ruby
+  end
+
+  class << self
+    # :nodoc:
+    ##
+    # Return the join path, with escaping backticks, dollars, and
+    # double-quotes.  Unlike `shellescape`, equal-sign is not escaped.
+
+    private
+
+    def escape_path(*path)
+      path = File.join(*path)
+      if %r{\A[-+:/=@,.\w]+\z} =~ path
+        path
+      else
+        "\"#{path.gsub(/[`$"]/, '\\&')}\""
+      end
+    end
+  end
+
+  @@good_rake = "#{rubybin} #{escape_path(__dir__, 'good_rake.rb')}"
+  @@bad_rake = "#{rubybin} #{escape_path(__dir__, 'bad_rake.rb')}"
+
+  ##
+  # Construct a new Gem::Dependency.
+
+  def dep(name, *requirements)
+    Gem::Dependency.new name, *requirements
+  end
+
+  ##
+  # Constructs a Gem::Resolver::DependencyRequest from a
+  # Gem::Dependency +dep+, a +from_name+ and +from_version+ requesting the
+  # dependency and a +parent+ DependencyRequest
+
+  def dependency_request(dep, from_name, from_version, parent = nil)
+    remote = Gem::Source.new @uri
+
+    unless parent
+      parent_dep = dep from_name, from_version
+      parent = Gem::Resolver::DependencyRequest.new parent_dep, nil
+    end
+
+    spec = Gem::Resolver::IndexSpecification.new \
+      nil, from_name, from_version, remote, Gem::Platform::RUBY
+    activation = Gem::Resolver::ActivationRequest.new spec, parent
+
+    Gem::Resolver::DependencyRequest.new dep, activation
+  end
+
+  ##
+  # Constructs a new Gem::Requirement.
+
+  def req(*requirements)
+    return requirements.first if Gem::Requirement === requirements.first
+    Gem::Requirement.create requirements
+  end
+
+  ##
+  # Constructs a new Gem::Specification.
+
+  def spec(name, version, &block)
+    Gem::Specification.new name, v(version), &block
+  end
+
+  ##
+  # Creates a SpecFetcher pre-filled with the gems or specs defined in the
+  # block.
+  #
+  # Yields a +fetcher+ object that responds to +spec+ and +gem+.  +spec+ adds
+  # a specification to the SpecFetcher while +gem+ adds both a specification
+  # and the gem data to the RemoteFetcher so the built gem can be downloaded.
+  #
+  # If only the a-3 gem is supposed to be downloaded you can save setup
+  # time by creating only specs for the other versions:
+  #
+  #   spec_fetcher do |fetcher|
+  #     fetcher.spec 'a', 1
+  #     fetcher.spec 'a', 2, 'b' => 3 # dependency on b = 3
+  #     fetcher.gem 'a', 3 do |spec|
+  #       # spec is a Gem::Specification
+  #       # ...
+  #     end
+  #   end
+
+  def spec_fetcher(repository = @gem_repo)
+    Gem::TestCase::SpecFetcherSetup.declare self, repository do |spec_fetcher_setup|
+      yield spec_fetcher_setup if block_given?
+    end
+  end
+
+  ##
+  # Construct a new Gem::Version.
+
+  def v(string)
+    Gem::Version.create string
+  end
+
+  ##
+  # A vendor_gem is used with a gem dependencies file.  The gem created here
+  # has no files, just a gem specification for the given +name+ and +version+.
+  #
+  # Yields the +specification+ to the block, if given
+
+  def vendor_gem(name = 'a', version = 1)
+    directory = File.join 'vendor', name
+
+    FileUtils.mkdir_p directory
+
+    save_gemspec name, version, directory
+  end
+
+  ##
+  # create_gemspec creates gem specification in given +directory+ or '.'
+  # for the given +name+ and +version+.
+  #
+  # Yields the +specification+ to the block, if given
+
+  def save_gemspec(name = 'a', version = 1, directory = '.')
+    vendor_spec = Gem::Specification.new name, version do |specification|
+      yield specification if block_given?
+    end
+
+    File.open File.join(directory, "#{name}.gemspec"), 'w' do |io|
+      io.write vendor_spec.to_ruby
+    end
+
+    return name, vendor_spec.version, directory
+  end
+
+  ##
+  # The StaticSet is a static set of gem specifications used for testing only.
+  # It is available by requiring Gem::TestCase.
+
+  class StaticSet < Gem::Resolver::Set
+    ##
+    # A StaticSet ignores remote because it has a fixed set of gems.
+
+    attr_accessor :remote
+
+    ##
+    # Creates a new StaticSet for the given +specs+
+
+    def initialize(specs)
+      super()
+
+      @specs = specs
+
+      @remote = true
+    end
+
+    ##
+    # Adds +spec+ to this set.
+
+    def add(spec)
+      @specs << spec
+    end
+
+    ##
+    # Finds +dep+ in this set.
+
+    def find_spec(dep)
+      @specs.reverse_each do |s|
+        return s if dep.matches_spec? s
+      end
+    end
+
+    ##
+    # Finds all gems matching +dep+ in this set.
+
+    def find_all(dep)
+      @specs.find_all {|s| dep.match? s, @prerelease }
+    end
+
+    ##
+    # Loads a Gem::Specification from this set which has the given +name+,
+    # version +ver+, +platform+.  The +source+ is ignored.
+
+    def load_spec(name, ver, platform, source)
+      dep = Gem::Dependency.new name, ver
+      spec = find_spec dep
+
+      Gem::Specification.new spec.name, spec.version do |s|
+        s.platform = spec.platform
+      end
+    end
+
+    def prefetch(reqs) # :nodoc:
+    end
+  end
+
+  ##
+  # Loads certificate named +cert_name+ from <tt>test/rubygems/</tt>.
+
+  def self.load_cert(cert_name)
+    cert_file = cert_path cert_name
+
+    cert = File.read cert_file
+
+    OpenSSL::X509::Certificate.new cert
+  end
+
+  ##
+  # Returns the path to the certificate named +cert_name+ from
+  # <tt>test/rubygems/</tt>.
+
+  def self.cert_path(cert_name)
+    if 32 == (Time.at(2**32) rescue 32)
+      cert_file = "#{__dir__}/#{cert_name}_cert_32.pem"
+
+      return cert_file if File.exist? cert_file
+    end
+
+    "#{__dir__}/#{cert_name}_cert.pem"
+  end
+
+  ##
+  # Loads an RSA private key named +key_name+ with +passphrase+ in <tt>test/rubygems/</tt>
+
+  def self.load_key(key_name, passphrase = nil)
+    key_file = key_path key_name
+
+    key = File.read key_file
+
+    OpenSSL::PKey::RSA.new key, passphrase
+  end
+
+  ##
+  # Returns the path to the key named +key_name+ from <tt>test/rubygems</tt>
+
+  def self.key_path(key_name)
+    "#{__dir__}/#{key_name}_key.pem"
+  end
+
+  # :stopdoc:
+  # only available in RubyGems tests
+
+  PRIVATE_KEY_PASSPHRASE = 'Foo bar'.freeze
+
+  begin
+    PRIVATE_KEY                 = load_key 'private'
+    PRIVATE_KEY_PATH            = key_path 'private'
+
+    # ENCRYPTED_PRIVATE_KEY is PRIVATE_KEY encrypted with PRIVATE_KEY_PASSPHRASE
+    ENCRYPTED_PRIVATE_KEY       = load_key 'encrypted_private', PRIVATE_KEY_PASSPHRASE
+    ENCRYPTED_PRIVATE_KEY_PATH  = key_path 'encrypted_private'
+
+    PUBLIC_KEY                  = PRIVATE_KEY.public_key
+
+    PUBLIC_CERT                 = load_cert 'public'
+    PUBLIC_CERT_PATH            = cert_path 'public'
+  rescue Errno::ENOENT
+    PRIVATE_KEY = nil
+    PUBLIC_KEY  = nil
+    PUBLIC_CERT = nil
+  end if Gem::HAVE_OPENSSL
+end
+
+# https://github.com/seattlerb/minitest/blob/13c48a03d84a2a87855a4de0c959f96800100357/lib/minitest/mock.rb#L192
+class Object
+  def stub(name, val_or_callable, *block_args)
+    new_name = "__minitest_stub__#{name}"
+
+    metaclass = class << self; self; end
+
+    if respond_to? name and not methods.map(&:to_s).include? name.to_s
+      metaclass.send :define_method, name do |*args|
+        super(*args)
+      end
+    end
+
+    metaclass.send :alias_method, new_name, name
+
+    metaclass.send :define_method, name do |*args, &blk|
+      if val_or_callable.respond_to? :call
+        val_or_callable.call(*args, &blk)
+      else
+        blk.call(*block_args) if blk
+        val_or_callable
+      end
+    end
+
+    metaclass.send(:ruby2_keywords, name) if metaclass.respond_to?(:ruby2_keywords, true)
+
+    yield self
+  ensure
+    metaclass.send :undef_method, name
+    metaclass.send :alias_method, name, new_name
+    metaclass.send :undef_method, new_name
+  end
+end
+
+require_relative 'utilities'
diff --git a/test/rubygems/installer_test_case.rb b/test/rubygems/installer_test_case.rb
new file mode 100644
index 0000000000..824ac53a82
--- /dev/null
+++ b/test/rubygems/installer_test_case.rb
@@ -0,0 +1,247 @@
+# frozen_string_literal: true
+require_relative 'helper'
+require 'rubygems/installer'
+
+class Gem::Installer
+  ##
+  # Available through requiring rubygems/installer_test_case
+
+  attr_writer :bin_dir
+
+  ##
+  # Available through requiring rubygems/installer_test_case
+
+  attr_writer :build_args
+
+  ##
+  # Available through requiring rubygems/installer_test_case
+
+  attr_writer :gem_dir
+
+  ##
+  # Available through requiring rubygems/installer_test_case
+
+  attr_writer :force
+
+  ##
+  # Available through requiring rubygems/installer_test_case
+
+  attr_writer :format
+
+  ##
+  # Available through requiring rubygems/installer_test_case
+
+  attr_writer :gem_home
+
+  ##
+  # Available through requiring rubygems/installer_test_case
+
+  attr_writer :env_shebang
+
+  ##
+  # Available through requiring rubygems/installer_test_case
+
+  attr_writer :ignore_dependencies
+
+  ##
+  # Available through requiring rubygems/installer_test_case
+
+  attr_writer :format_executable
+
+  ##
+  # Available through requiring rubygems/installer_test_case
+
+  attr_writer :security_policy
+
+  ##
+  # Available through requiring rubygems/installer_test_case
+
+  attr_writer :wrappers
+end
+
+##
+# A test case for Gem::Installer.
+
+class Gem::InstallerTestCase < Gem::TestCase
+  def setup
+    super
+
+    Gem::Installer.path_warning = false
+  end
+
+  ##
+  # The path where installed executables live
+
+  def util_inst_bindir
+    File.join @gemhome, "bin"
+  end
+
+  ##
+  # Adds an executable named "executable" to +spec+ with the given +shebang+.
+  #
+  # The executable is also written to the bin dir in @tmpdir and the installed
+  # gem directory for +spec+.
+
+  def util_make_exec(spec = @spec, shebang = "#!/usr/bin/ruby", bindir = "bin")
+    spec.executables = %w[executable]
+    spec.bindir = bindir
+
+    exec_path = spec.bin_file "executable"
+    write_file exec_path do |io|
+      io.puts shebang
+    end
+
+    bin_path = File.join @tempdir, "bin", "executable"
+    write_file bin_path do |io|
+      io.puts shebang
+    end
+  end
+
+  ##
+  # Creates the following instance variables:
+  #
+  # @spec::
+  #   a spec named 'a', intended for regular installs
+  #
+  # @gem::
+  #   the path to a built gem from @spec
+  #
+  # And returns a Gem::Installer for the @spec that installs into @gemhome
+
+  def setup_base_installer(force = true)
+    @gem = setup_base_gem
+    util_installer @spec, @gemhome, false, force
+  end
+
+  ##
+  # Creates the following instance variables:
+  #
+  # @spec::
+  #   a spec named 'a', intended for regular installs
+  #
+  # And returns a gem built for the @spec
+
+  def setup_base_gem
+    @spec = setup_base_spec
+    util_build_gem @spec
+    @spec.cache_file
+  end
+
+  ##
+  # Sets up a generic specification for testing the rubygems installer
+  #
+  # And returns it
+
+  def setup_base_spec
+    quick_gem 'a' do |spec|
+      util_make_exec spec
+    end
+  end
+
+  ##
+  # Creates the following instance variables:
+  #
+  # @spec::
+  #   a spec named 'a', intended for regular installs
+  # @user_spec::
+  #   a spec named 'b', intended for user installs
+  #
+  # @gem::
+  #   the path to a built gem from @spec
+  # @user_gem::
+  #   the path to a built gem from @user_spec
+  #
+  # And returns a Gem::Installer for the @user_spec that installs into Gem.user_dir
+
+  def setup_base_user_installer
+    @user_spec = quick_gem 'b' do |spec|
+      util_make_exec spec
+    end
+
+    util_build_gem @user_spec
+
+    @user_gem = @user_spec.cache_file
+
+    util_installer @user_spec, Gem.user_dir, :user
+  end
+
+  ##
+  # Sets up the base @gem, builds it and returns an installer for it.
+  #
+  def util_setup_installer(&block)
+    @gem = setup_base_gem
+
+    util_setup_gem(&block)
+  end
+
+  ##
+  # Builds the @spec gem and returns an installer for it.  The built gem
+  # includes:
+  #
+  #   bin/executable
+  #   lib/code.rb
+  #   ext/a/mkrf_conf.rb
+
+  def util_setup_gem(ui = @ui, force = true)
+    @spec.files << File.join('lib', 'code.rb')
+    @spec.extensions << File.join('ext', 'a', 'mkrf_conf.rb')
+
+    Dir.chdir @tempdir do
+      FileUtils.mkdir_p 'bin'
+      FileUtils.mkdir_p 'lib'
+      FileUtils.mkdir_p File.join('ext', 'a')
+
+      File.open File.join('bin', 'executable'), 'w' do |f|
+        f.puts "raise 'ran executable'"
+      end
+
+      File.open File.join('lib', 'code.rb'), 'w' do |f|
+        f.puts '1'
+      end
+
+      File.open File.join('ext', 'a', 'mkrf_conf.rb'), 'w' do |f|
+        f << <<-EOF
+          File.open 'Rakefile', 'w' do |rf| rf.puts "task :default" end
+        EOF
+      end
+
+      yield @spec if block_given?
+
+      use_ui ui do
+        FileUtils.rm_f @gem
+
+        @gem = Gem::Package.build @spec
+      end
+    end
+
+    Gem::Installer.at @gem, :force => force
+  end
+
+  ##
+  # Creates an installer for +spec+ that will install into +gem_home+.  If
+  # +user+ is true a user-install will be performed.
+
+  def util_installer(spec, gem_home, user=false, force=true)
+    Gem::Installer.at(spec.cache_file,
+                       :install_dir => gem_home,
+                       :user_install => user,
+                       :force => force)
+  end
+
+  @@symlink_supported = nil
+
+  # This is needed for Windows environment without symlink support enabled (the default
+  # for non admin) to be able to skip test for features using symlinks.
+  def symlink_supported?
+    if @@symlink_supported.nil?
+      begin
+        File.symlink("", "")
+      rescue Errno::ENOENT, Errno::EEXIST
+        @@symlink_supported = true
+      rescue NotImplementedError, SystemCallError
+        @@symlink_supported = false
+      end
+    end
+    @@symlink_supported
+  end
+end
diff --git a/test/rubygems/package/tar_test_case.rb b/test/rubygems/package/tar_test_case.rb
new file mode 100644
index 0000000000..99f503a23f
--- /dev/null
+++ b/test/rubygems/package/tar_test_case.rb
@@ -0,0 +1,139 @@
+# frozen_string_literal: true
+require_relative '../helper'
+require 'rubygems/package'
+
+##
+# A test case for Gem::Package::Tar* classes
+
+class Gem::Package::TarTestCase < Gem::TestCase
+  def ASCIIZ(str, length)
+    str + "\0" * (length - str.length)
+  end
+
+  def SP(s)
+    s + " "
+  end
+
+  def SP_Z(s)
+    s + " \0"
+  end
+
+  def Z(s)
+    s + "\0"
+  end
+
+  def assert_headers_equal(expected, actual)
+    expected = expected.to_s unless String === expected
+    actual = actual.to_s unless String === actual
+
+    fields = %w[
+      name 100
+      mode 8
+      uid 8
+      gid 8
+      size 12
+      mtime 12
+      checksum 8
+      typeflag 1
+      linkname 100
+      magic 6
+      version 2
+      uname 32
+      gname 32
+      devmajor 8
+      devminor 8
+      prefix 155
+    ]
+
+    offset = 0
+
+    until fields.empty? do
+      name = fields.shift
+      length = fields.shift.to_i
+
+      if name == "checksum"
+        chksum_off = offset
+        offset += length
+        next
+      end
+
+      assert_equal expected[offset, length], actual[offset, length],
+                   "Field #{name} of the tar header differs."
+
+      offset += length
+    end
+
+    assert_equal expected[chksum_off, 8], actual[chksum_off, 8]
+  end
+
+  def calc_checksum(header)
+    sum = header.unpack("C*").inject{|s,a| s + a }
+    SP(Z(to_oct(sum, 6)))
+  end
+
+  def header(type, fname, dname, length, mode, mtime, checksum = nil, linkname = "")
+    checksum ||= " " * 8
+
+    arr = [                  # struct tarfile_entry_posix
+      ASCIIZ(fname, 100),    # char name[100];     ASCII + (Z unless filled)
+      Z(to_oct(mode, 7)),    # char mode[8];       0 padded, octal null
+      Z(to_oct(0, 7)),       # char uid[8];        ditto
+      Z(to_oct(0, 7)),       # char gid[8];        ditto
+      Z(to_oct(length, 11)), # char size[12];      0 padded, octal, null
+      Z(to_oct(mtime, 11)),  # char mtime[12];     0 padded, octal, null
+      checksum,              # char checksum[8];   0 padded, octal, null, space
+      type,                  # char typeflag[1];   file: "0"  dir: "5"
+      ASCIIZ(linkname, 100), # char linkname[100]; ASCII + (Z unless filled)
+      "ustar\0",             # char magic[6];      "ustar\0"
+      "00",                  # char version[2];    "00"
+      ASCIIZ("wheel", 32),   # char uname[32];     ASCIIZ
+      ASCIIZ("wheel", 32),   # char gname[32];     ASCIIZ
+      Z(to_oct(0, 7)),       # char devmajor[8];   0 padded, octal, null
+      Z(to_oct(0, 7)),       # char devminor[8];   0 padded, octal, null
+      ASCIIZ(dname, 155), # char prefix[155];   ASCII + (Z unless filled)
+    ]
+
+    h = arr.join
+    ret = h + "\0" * (512 - h.size)
+    assert_equal(512, ret.size)
+    ret
+  end
+
+  def tar_dir_header(name, prefix, mode, mtime)
+    h = header("5", name, prefix, 0, mode, mtime)
+    checksum = calc_checksum(h)
+    header("5", name, prefix, 0, mode, mtime, checksum)
+  end
+
+  def tar_file_header(fname, dname, mode, length, mtime)
+    h = header("0", fname, dname, length, mode, mtime)
+    checksum = calc_checksum(h)
+    header("0", fname, dname, length, mode, mtime, checksum)
+  end
+
+  def tar_symlink_header(fname, prefix, mode, mtime, linkname)
+    h = header("2", fname, prefix, 0, mode, mtime, nil, linkname)
+    checksum = calc_checksum(h)
+    header("2", fname, prefix, 0, mode, mtime, checksum, linkname)
+  end
+
+  def to_oct(n, pad_size)
+    "%0#{pad_size}o" % n
+  end
+
+  def util_entry(tar)
+    io = TempIO.new tar
+
+    header = Gem::Package::TarHeader.from io
+
+    Gem::Package::TarReader::Entry.new header, io
+  end
+
+  def util_dir_entry
+    util_entry tar_dir_header("foo", "bar", 0, Time.now)
+  end
+
+  def util_symlink_entry
+    util_entry tar_symlink_header("foo", "bar", 0, Time.now, "link")
+  end
+end
diff --git a/test/rubygems/test_bundled_ca.rb b/test/rubygems/test_bundled_ca.rb
index ff5b8dba19..fff5904aba 100644
--- a/test/rubygems/test_bundled_ca.rb
+++ b/test/rubygems/test_bundled_ca.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'net/http'
 require 'rubygems/openssl'
 
diff --git a/test/rubygems/test_config.rb b/test/rubygems/test_config.rb
index 015e2b1d8a..4d64f16fca 100644
--- a/test/rubygems/test_config.rb
+++ b/test/rubygems/test_config.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems'
 require 'shellwords'
 
diff --git a/test/rubygems/test_deprecate.rb b/test/rubygems/test_deprecate.rb
index 4a14266ce3..a619eccb37 100644
--- a/test/rubygems/test_deprecate.rb
+++ b/test/rubygems/test_deprecate.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/deprecate'
 
 class TestDeprecate < Gem::TestCase
diff --git a/test/rubygems/test_gem.rb b/test/rubygems/test_gem.rb
index d548e95fd7..79ea89e2fa 100644
--- a/test/rubygems/test_gem.rb
+++ b/test/rubygems/test_gem.rb
@@ -1,5 +1,5 @@
 # coding: US-ASCII
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems'
 require 'rubygems/command'
 require 'rubygems/installer'
diff --git a/test/rubygems/test_gem_available_set.rb b/test/rubygems/test_gem_available_set.rb
index dd2816acc6..c4164d77f2 100644
--- a/test/rubygems/test_gem_available_set.rb
+++ b/test/rubygems/test_gem_available_set.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/available_set'
 require 'rubygems/security'
 
diff --git a/test/rubygems/test_gem_bundler_version_finder.rb b/test/rubygems/test_gem_bundler_version_finder.rb
index 4126898048..e971e6ae29 100644
--- a/test/rubygems/test_gem_bundler_version_finder.rb
+++ b/test/rubygems/test_gem_bundler_version_finder.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestGemBundlerVersionFinder < Gem::TestCase
   def setup
diff --git a/test/rubygems/test_gem_command.rb b/test/rubygems/test_gem_command.rb
index 4d0c4eb5e8..43ce6ea39f 100644
--- a/test/rubygems/test_gem_command.rb
+++ b/test/rubygems/test_gem_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/command'
 
 class Gem::Command
diff --git a/test/rubygems/test_gem_command_manager.rb b/test/rubygems/test_gem_command_manager.rb
index d9c74191cd..6225576367 100644
--- a/test/rubygems/test_gem_command_manager.rb
+++ b/test/rubygems/test_gem_command_manager.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/command_manager'
 
 class TestGemCommandManager < Gem::TestCase
diff --git a/test/rubygems/test_gem_commands_build_command.rb b/test/rubygems/test_gem_commands_build_command.rb
index 3adf69cdf4..1304beb580 100644
--- a/test/rubygems/test_gem_commands_build_command.rb
+++ b/test/rubygems/test_gem_commands_build_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/build_command'
 require 'rubygems/package'
 
diff --git a/test/rubygems/test_gem_commands_cert_command.rb b/test/rubygems/test_gem_commands_cert_command.rb
index e8b6e506f5..f722678a19 100644
--- a/test/rubygems/test_gem_commands_cert_command.rb
+++ b/test/rubygems/test_gem_commands_cert_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/cert_command'
 
 unless Gem::HAVE_OPENSSL
diff --git a/test/rubygems/test_gem_commands_check_command.rb b/test/rubygems/test_gem_commands_check_command.rb
index 07eea188e3..f280b060c4 100644
--- a/test/rubygems/test_gem_commands_check_command.rb
+++ b/test/rubygems/test_gem_commands_check_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/check_command'
 
 class TestGemCommandsCheckCommand < Gem::TestCase
diff --git a/test/rubygems/test_gem_commands_cleanup_command.rb b/test/rubygems/test_gem_commands_cleanup_command.rb
index 6e21e8c68b..fc98998012 100644
--- a/test/rubygems/test_gem_commands_cleanup_command.rb
+++ b/test/rubygems/test_gem_commands_cleanup_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/cleanup_command'
 require 'rubygems/installer'
 
diff --git a/test/rubygems/test_gem_commands_contents_command.rb b/test/rubygems/test_gem_commands_contents_command.rb
index 2b04a9c654..d79174717b 100644
--- a/test/rubygems/test_gem_commands_contents_command.rb
+++ b/test/rubygems/test_gem_commands_contents_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/contents_command'
 
 class TestGemCommandsContentsCommand < Gem::TestCase
diff --git a/test/rubygems/test_gem_commands_dependency_command.rb b/test/rubygems/test_gem_commands_dependency_command.rb
index d49aa2f513..13c7c065b5 100644
--- a/test/rubygems/test_gem_commands_dependency_command.rb
+++ b/test/rubygems/test_gem_commands_dependency_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/dependency_command'
 
 class TestGemCommandsDependencyCommand < Gem::TestCase
diff --git a/test/rubygems/test_gem_commands_environment_command.rb b/test/rubygems/test_gem_commands_environment_command.rb
index c31ca24869..2bf80d8d85 100644
--- a/test/rubygems/test_gem_commands_environment_command.rb
+++ b/test/rubygems/test_gem_commands_environment_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/environment_command'
 
 class TestGemCommandsEnvironmentCommand < Gem::TestCase
diff --git a/test/rubygems/test_gem_commands_fetch_command.rb b/test/rubygems/test_gem_commands_fetch_command.rb
index 9a81e8898e..35ee00f763 100644
--- a/test/rubygems/test_gem_commands_fetch_command.rb
+++ b/test/rubygems/test_gem_commands_fetch_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/package'
 require 'rubygems/security'
 require 'rubygems/commands/fetch_command'
diff --git a/test/rubygems/test_gem_commands_generate_index_command.rb b/test/rubygems/test_gem_commands_generate_index_command.rb
index fc1317a49d..5b7b37a446 100644
--- a/test/rubygems/test_gem_commands_generate_index_command.rb
+++ b/test/rubygems/test_gem_commands_generate_index_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/indexer'
 require 'rubygems/commands/generate_index_command'
 
diff --git a/test/rubygems/test_gem_commands_help_command.rb b/test/rubygems/test_gem_commands_help_command.rb
index 128db5db1f..a70dd770e1 100644
--- a/test/rubygems/test_gem_commands_help_command.rb
+++ b/test/rubygems/test_gem_commands_help_command.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 require "rubygems"
-require "rubygems/test_case"
+require_relative "helper"
 require "rubygems/commands/help_command"
 require "rubygems/package"
 require "rubygems/command_manager"
diff --git a/test/rubygems/test_gem_commands_info_command.rb b/test/rubygems/test_gem_commands_info_command.rb
index 6d67b567c7..462075f98c 100644
--- a/test/rubygems/test_gem_commands_info_command.rb
+++ b/test/rubygems/test_gem_commands_info_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/info_command'
 
 class TestGemCommandsInfoCommand < Gem::TestCase
diff --git a/test/rubygems/test_gem_commands_install_command.rb b/test/rubygems/test_gem_commands_install_command.rb
index c51bbf810d..48ac040d0e 100644
--- a/test/rubygems/test_gem_commands_install_command.rb
+++ b/test/rubygems/test_gem_commands_install_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/install_command'
 require 'rubygems/request_set'
 require 'rubygems/rdoc'
diff --git a/test/rubygems/test_gem_commands_list_command.rb b/test/rubygems/test_gem_commands_list_command.rb
index 772a99eabd..d8cffce7a3 100644
--- a/test/rubygems/test_gem_commands_list_command.rb
+++ b/test/rubygems/test_gem_commands_list_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/list_command'
 
 class TestGemCommandsListCommand < Gem::TestCase
diff --git a/test/rubygems/test_gem_commands_lock_command.rb b/test/rubygems/test_gem_commands_lock_command.rb
index 81252e6409..f8afca1e29 100644
--- a/test/rubygems/test_gem_commands_lock_command.rb
+++ b/test/rubygems/test_gem_commands_lock_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/lock_command'
 
 class TestGemCommandsLockCommand < Gem::TestCase
diff --git a/test/rubygems/test_gem_commands_mirror.rb b/test/rubygems/test_gem_commands_mirror.rb
index 6b2b7d11bb..470f1c30fa 100644
--- a/test/rubygems/test_gem_commands_mirror.rb
+++ b/test/rubygems/test_gem_commands_mirror.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/mirror_command'
 
 class TestGemCommandsMirrorCommand < Gem::TestCase
diff --git a/test/rubygems/test_gem_commands_open_command.rb b/test/rubygems/test_gem_commands_open_command.rb
index 2c32b810cc..8447f7ea35 100644
--- a/test/rubygems/test_gem_commands_open_command.rb
+++ b/test/rubygems/test_gem_commands_open_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/open_command'
 
 class TestGemCommandsOpenCommand < Gem::TestCase
diff --git a/test/rubygems/test_gem_commands_outdated_command.rb b/test/rubygems/test_gem_commands_outdated_command.rb
index c4af421f5d..dc5c40a782 100644
--- a/test/rubygems/test_gem_commands_outdated_command.rb
+++ b/test/rubygems/test_gem_commands_outdated_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/outdated_command'
 
 class TestGemCommandsOutdatedCommand < Gem::TestCase
diff --git a/test/rubygems/test_gem_commands_owner_command.rb b/test/rubygems/test_gem_commands_owner_command.rb
index 730048e0ff..5b06b628c2 100644
--- a/test/rubygems/test_gem_commands_owner_command.rb
+++ b/test/rubygems/test_gem_commands_owner_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/owner_command'
 
 class TestGemCommandsOwnerCommand < Gem::TestCase
diff --git a/test/rubygems/test_gem_commands_pristine_command.rb b/test/rubygems/test_gem_commands_pristine_command.rb
index 118b2334fc..f4000f4657 100644
--- a/test/rubygems/test_gem_commands_pristine_command.rb
+++ b/test/rubygems/test_gem_commands_pristine_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/pristine_command'
 
 class TestGemCommandsPristineCommand < Gem::TestCase
diff --git a/test/rubygems/test_gem_commands_push_command.rb b/test/rubygems/test_gem_commands_push_command.rb
index 202e44e620..fa3968ffce 100644
--- a/test/rubygems/test_gem_commands_push_command.rb
+++ b/test/rubygems/test_gem_commands_push_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/push_command'
 
 class TestGemCommandsPushCommand < Gem::TestCase
diff --git a/test/rubygems/test_gem_commands_query_command.rb b/test/rubygems/test_gem_commands_query_command.rb
index cb95f185ab..0cc88b1685 100644
--- a/test/rubygems/test_gem_commands_query_command.rb
+++ b/test/rubygems/test_gem_commands_query_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/query_command'
 
 module TestGemCommandsQueryCommandSetup
diff --git a/test/rubygems/test_gem_commands_search_command.rb b/test/rubygems/test_gem_commands_search_command.rb
index 17693e6837..6397dbd4d4 100644
--- a/test/rubygems/test_gem_commands_search_command.rb
+++ b/test/rubygems/test_gem_commands_search_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/search_command'
 
 class TestGemCommandsSearchCommand < Gem::TestCase
diff --git a/test/rubygems/test_gem_commands_server_command.rb b/test/rubygems/test_gem_commands_server_command.rb
index 36c1feaec2..09cec63c15 100644
--- a/test/rubygems/test_gem_commands_server_command.rb
+++ b/test/rubygems/test_gem_commands_server_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/server_command'
 
 class TestGemCommandsServerCommand < Gem::TestCase
diff --git a/test/rubygems/test_gem_commands_setup_command.rb b/test/rubygems/test_gem_commands_setup_command.rb
index 93646550c1..3aa6bfa2fe 100644
--- a/test/rubygems/test_gem_commands_setup_command.rb
+++ b/test/rubygems/test_gem_commands_setup_command.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/setup_command'
 
 class TestGemCommandsSetupCommand < Gem::TestCase
@@ -21,7 +21,7 @@ class TestGemCommandsSetupCommand < Gem::TestCase
     filelist = %w[
       bin/gem
       lib/rubygems.rb
-      lib/rubygems/test_case.rb
+      lib/rubygems/requirement.rb
       lib/rubygems/ssl_certs/rubygems.org/foo.pem
       bundler/exe/bundle
       bundler/exe/bundler
@@ -159,7 +159,7 @@ class TestGemCommandsSetupCommand < Gem::TestCase
   end
 
   def test_files_in
-    assert_equal %w[rubygems.rb rubygems/ssl_certs/rubygems.org/foo.pem rubygems/test_case.rb],
+    assert_equal %w[rubygems.rb rubygems/requirement.rb rubygems/ssl_certs/rubygems.org/foo.pem],
                  @cmd.files_in('lib').sort
   end
 
diff --git a/test/rubygems/test_gem_commands_signin_command.rb b/test/rubygems/test_gem_commands_signin_command.rb
index d895d90b0c..eaf32886b3 100644
--- a/test/rubygems/test_gem_commands_signin_command.rb
+++ b/test/rubygems/test_gem_commands_signin_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/signin_command'
 require 'rubygems/installer'
 
diff --git a/test/rubygems/test_gem_commands_signout_command.rb b/test/rubygems/test_gem_commands_signout_command.rb
index 20389d0537..aa6300b6ab 100644
--- a/test/rubygems/test_gem_commands_signout_command.rb
+++ b/test/rubygems/test_gem_commands_signout_command.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/signout_command'
 require 'rubygems/installer'
 
diff --git a/test/rubygems/test_gem_commands_sources_command.rb b/test/rubygems/test_gem_commands_sources_command.rb
index 70d1b3611c..7bca0f3803 100644
--- a/test/rubygems/test_gem_commands_sources_command.rb
+++ b/test/rubygems/test_gem_commands_sources_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/sources_command'
 
 class TestGemCommandsSourcesCommand < Gem::TestCase
diff --git a/test/rubygems/test_gem_commands_specification_command.rb b/test/rubygems/test_gem_commands_specification_command.rb
index a04746f82c..c8cb7df32e 100644
--- a/test/rubygems/test_gem_commands_specification_command.rb
+++ b/test/rubygems/test_gem_commands_specification_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/specification_command'
 
 class TestGemCommandsSpecificationCommand < Gem::TestCase
diff --git a/test/rubygems/test_gem_commands_stale_command.rb b/test/rubygems/test_gem_commands_stale_command.rb
index 0aa7f243e2..83bd3e5def 100644
--- a/test/rubygems/test_gem_commands_stale_command.rb
+++ b/test/rubygems/test_gem_commands_stale_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/stale_command'
 
 class TestGemCommandsStaleCommand < Gem::TestCase
diff --git a/test/rubygems/test_gem_commands_uninstall_command.rb b/test/rubygems/test_gem_commands_uninstall_command.rb
index a1b81d73de..55f1049266 100644
--- a/test/rubygems/test_gem_commands_uninstall_command.rb
+++ b/test/rubygems/test_gem_commands_uninstall_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/installer_test_case'
+require_relative 'installer_test_case'
 require 'rubygems/commands/uninstall_command'
 
 class TestGemCommandsUninstallCommand < Gem::InstallerTestCase
diff --git a/test/rubygems/test_gem_commands_unpack_command.rb b/test/rubygems/test_gem_commands_unpack_command.rb
index f2f60f02bf..55369f1eeb 100644
--- a/test/rubygems/test_gem_commands_unpack_command.rb
+++ b/test/rubygems/test_gem_commands_unpack_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/unpack_command'
 
 class TestGemCommandsUnpackCommand < Gem::TestCase
diff --git a/test/rubygems/test_gem_commands_update_command.rb b/test/rubygems/test_gem_commands_update_command.rb
index 3224391018..a7ddddf2c1 100644
--- a/test/rubygems/test_gem_commands_update_command.rb
+++ b/test/rubygems/test_gem_commands_update_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/update_command'
 
 class TestGemCommandsUpdateCommand < Gem::TestCase
diff --git a/test/rubygems/test_gem_commands_which_command.rb b/test/rubygems/test_gem_commands_which_command.rb
index ce56f8eefc..a398dc5708 100644
--- a/test/rubygems/test_gem_commands_which_command.rb
+++ b/test/rubygems/test_gem_commands_which_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/which_command'
 
 class TestGemCommandsWhichCommand < Gem::TestCase
diff --git a/test/rubygems/test_gem_commands_yank_command.rb b/test/rubygems/test_gem_commands_yank_command.rb
index 76e935b06a..3b0956e1c4 100644
--- a/test/rubygems/test_gem_commands_yank_command.rb
+++ b/test/rubygems/test_gem_commands_yank_command.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/commands/yank_command'
 
 class TestGemCommandsYankCommand < Gem::TestCase
diff --git a/test/rubygems/test_gem_config_file.rb b/test/rubygems/test_gem_config_file.rb
index 77d7a08bb8..32375e6936 100644
--- a/test/rubygems/test_gem_config_file.rb
+++ b/test/rubygems/test_gem_config_file.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/config_file'
 
 class TestGemConfigFile < Gem::TestCase
diff --git a/test/rubygems/test_gem_dependency.rb b/test/rubygems/test_gem_dependency.rb
index d4ef220064..1ca0fc378c 100644
--- a/test/rubygems/test_gem_dependency.rb
+++ b/test/rubygems/test_gem_dependency.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/dependency'
 
 class TestGemDependency < Gem::TestCase
diff --git a/test/rubygems/test_gem_dependency_installer.rb b/test/rubygems/test_gem_dependency_installer.rb
index 90d5d16403..9cbdcefea4 100644
--- a/test/rubygems/test_gem_dependency_installer.rb
+++ b/test/rubygems/test_gem_dependency_installer.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/dependency_installer'
 require 'rubygems/security'
 
diff --git a/test/rubygems/test_gem_dependency_list.rb b/test/rubygems/test_gem_dependency_list.rb
index 097e680596..15c50de199 100644
--- a/test/rubygems/test_gem_dependency_list.rb
+++ b/test/rubygems/test_gem_dependency_list.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/dependency_list'
 
 class TestGemDependencyList < Gem::TestCase
diff --git a/test/rubygems/test_gem_dependency_resolution_error.rb b/test/rubygems/test_gem_dependency_resolution_error.rb
index 5321f7031c..0e4a2fe31a 100644
--- a/test/rubygems/test_gem_dependency_resolution_error.rb
+++ b/test/rubygems/test_gem_dependency_resolution_error.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestGemDependencyResolutionError < Gem::TestCase
   def setup
diff --git a/test/rubygems/test_gem_doctor.rb b/test/rubygems/test_gem_doctor.rb
index 4514d17f9f..583c735dd3 100644
--- a/test/rubygems/test_gem_doctor.rb
+++ b/test/rubygems/test_gem_doctor.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/doctor'
 
 class TestGemDoctor < Gem::TestCase
diff --git a/test/rubygems/test_gem_ext_builder.rb b/test/rubygems/test_gem_ext_builder.rb
index 36d5328aef..165194510e 100644
--- a/test/rubygems/test_gem_ext_builder.rb
+++ b/test/rubygems/test_gem_ext_builder.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/ext'
 require 'rubygems/installer'
 
@@ -106,6 +106,7 @@ install:
   end
 
   def test_build_extensions
+    pend if /mswin/ =~ RUBY_PLATFORM && ENV.key?('GITHUB_ACTIONS') # not working from the beginning
     @spec.extensions << 'ext/extconf.rb'
 
     ext_dir = File.join @spec.gem_dir, 'ext'
@@ -141,6 +142,7 @@ install:
   end
 
   def test_build_extensions_with_gemhome_with_space
+    pend if /mswin/ =~ RUBY_PLATFORM && ENV.key?('GITHUB_ACTIONS') # not working from the beginning
     new_gemhome = File.join @tempdir, 'gem home'
     File.rename(@gemhome, new_gemhome)
     @gemhome = new_gemhome
@@ -161,6 +163,7 @@ install:
         false
       end
     end
+    pend if /mswin/ =~ RUBY_PLATFORM && ENV.key?('GITHUB_ACTIONS') # not working from the beginning
 
     @spec.extensions << 'ext/extconf.rb'
 
diff --git a/test/rubygems/test_gem_ext_cmake_builder.rb b/test/rubygems/test_gem_ext_cmake_builder.rb
index 47d06efbca..5ab82c545f 100644
--- a/test/rubygems/test_gem_ext_cmake_builder.rb
+++ b/test/rubygems/test_gem_ext_cmake_builder.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/ext'
 
 class TestGemExtCmakeBuilder < Gem::TestCase
diff --git a/test/rubygems/test_gem_ext_configure_builder.rb b/test/rubygems/test_gem_ext_configure_builder.rb
index 87260bcfa2..76ccfe2dc4 100644
--- a/test/rubygems/test_gem_ext_configure_builder.rb
+++ b/test/rubygems/test_gem_ext_configure_builder.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/ext'
 
 class TestGemExtConfigureBuilder < Gem::TestCase
diff --git a/test/rubygems/test_gem_ext_ext_conf_builder.rb b/test/rubygems/test_gem_ext_ext_conf_builder.rb
index 02b46ad8b7..70833f35cf 100644
--- a/test/rubygems/test_gem_ext_ext_conf_builder.rb
+++ b/test/rubygems/test_gem_ext_ext_conf_builder.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/ext'
 
 class TestGemExtExtConfBuilder < Gem::TestCase
diff --git a/test/rubygems/test_gem_ext_rake_builder.rb b/test/rubygems/test_gem_ext_rake_builder.rb
index 505f42ba06..3d8922eed5 100644
--- a/test/rubygems/test_gem_ext_rake_builder.rb
+++ b/test/rubygems/test_gem_ext_rake_builder.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/ext'
 
 class TestGemExtRakeBuilder < Gem::TestCase
diff --git a/test/rubygems/test_gem_gem_runner.rb b/test/rubygems/test_gem_gem_runner.rb
index 8df11ecebc..6f5361cf2f 100644
--- a/test/rubygems/test_gem_gem_runner.rb
+++ b/test/rubygems/test_gem_gem_runner.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestGemGemRunner < Gem::TestCase
   def setup
diff --git a/test/rubygems/test_gem_gemcutter_utilities.rb b/test/rubygems/test_gem_gemcutter_utilities.rb
index fa9f951f8e..0bcd1504e9 100644
--- a/test/rubygems/test_gem_gemcutter_utilities.rb
+++ b/test/rubygems/test_gem_gemcutter_utilities.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems'
 require 'rubygems/command'
 require 'rubygems/gemcutter_utilities'
diff --git a/test/rubygems/test_gem_impossible_dependencies_error.rb b/test/rubygems/test_gem_impossible_dependencies_error.rb
index e4fe6ef77c..971be151df 100644
--- a/test/rubygems/test_gem_impossible_dependencies_error.rb
+++ b/test/rubygems/test_gem_impossible_dependencies_error.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestGemImpossibleDependenciesError < Gem::TestCase
   def test_message_conflict
diff --git a/test/rubygems/test_gem_indexer.rb b/test/rubygems/test_gem_indexer.rb
index adc83dd8fb..6653f29adf 100644
--- a/test/rubygems/test_gem_indexer.rb
+++ b/test/rubygems/test_gem_indexer.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/indexer'
 
 class TestGemIndexer < Gem::TestCase
diff --git a/test/rubygems/test_gem_install_update_options.rb b/test/rubygems/test_gem_install_update_options.rb
index 1afac10f73..33cb5c08bf 100644
--- a/test/rubygems/test_gem_install_update_options.rb
+++ b/test/rubygems/test_gem_install_update_options.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/installer_test_case'
+require_relative 'installer_test_case'
 require 'rubygems/install_update_options'
 require 'rubygems/command'
 require 'rubygems/dependency_installer'
diff --git a/test/rubygems/test_gem_installer.rb b/test/rubygems/test_gem_installer.rb
index 0a73425f93..a2b390d639 100644
--- a/test/rubygems/test_gem_installer.rb
+++ b/test/rubygems/test_gem_installer.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/installer_test_case'
+require_relative 'installer_test_case'
 
 class TestGemInstaller < Gem::InstallerTestCase
   def setup
@@ -740,7 +740,6 @@ gem 'other', version
 
     installer = Gem::Installer.at(
       gem_with_dangling_symlink,
-      :install_dir => @gem_home,
       :user_install => false,
       :force => true
     )
@@ -1482,6 +1481,7 @@ gem 'other', version
 
   def test_install_extension_and_script
     pend "Makefile creation crashes on jruby" if Gem.java_platform?
+    pend if /mswin/ =~ RUBY_PLATFORM && ENV.key?('GITHUB_ACTIONS') # not working from the beginning
 
     @spec = setup_base_spec
     @spec.extensions << "extconf.rb"
diff --git a/test/rubygems/test_gem_local_remote_options.rb b/test/rubygems/test_gem_local_remote_options.rb
index 2373bbde1f..948d1e3981 100644
--- a/test/rubygems/test_gem_local_remote_options.rb
+++ b/test/rubygems/test_gem_local_remote_options.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/local_remote_options'
 require 'rubygems/command'
 
diff --git a/test/rubygems/test_gem_name_tuple.rb b/test/rubygems/test_gem_name_tuple.rb
index 92cfe6c1d2..d87db9bc45 100644
--- a/test/rubygems/test_gem_name_tuple.rb
+++ b/test/rubygems/test_gem_name_tuple.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/name_tuple'
 
 class TestGemNameTuple < Gem::TestCase
diff --git a/test/rubygems/test_gem_package.rb b/test/rubygems/test_gem_package.rb
index 4cb8b9f981..3fa2c1911c 100644
--- a/test/rubygems/test_gem_package.rb
+++ b/test/rubygems/test_gem_package.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-require 'rubygems/package/tar_test_case'
+require_relative 'package/tar_test_case'
 require 'digest'
 
 class TestGemPackage < Gem::Package::TarTestCase
diff --git a/test/rubygems/test_gem_package_old.rb b/test/rubygems/test_gem_package_old.rb
index 3477e001dc..945340a96a 100644
--- a/test/rubygems/test_gem_package_old.rb
+++ b/test/rubygems/test_gem_package_old.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 unless Gem.java_platform? # jruby can't require the simple_gem file
   require 'rubygems/simple_gem'
diff --git a/test/rubygems/test_gem_package_tar_header.rb b/test/rubygems/test_gem_package_tar_header.rb
index 9f321e0a77..0e72a72d6a 100644
--- a/test/rubygems/test_gem_package_tar_header.rb
+++ b/test/rubygems/test_gem_package_tar_header.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/package/tar_test_case'
+require_relative 'package/tar_test_case'
 require 'rubygems/package'
 
 class TestGemPackageTarHeader < Gem::Package::TarTestCase
diff --git a/test/rubygems/test_gem_package_tar_reader.rb b/test/rubygems/test_gem_package_tar_reader.rb
index 05b3ac56a6..277b552f1b 100644
--- a/test/rubygems/test_gem_package_tar_reader.rb
+++ b/test/rubygems/test_gem_package_tar_reader.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/package/tar_test_case'
+require_relative 'package/tar_test_case'
 require 'rubygems/package'
 
 class TestGemPackageTarReader < Gem::Package::TarTestCase
diff --git a/test/rubygems/test_gem_package_tar_reader_entry.rb b/test/rubygems/test_gem_package_tar_reader_entry.rb
index bf20388f59..1be5870146 100644
--- a/test/rubygems/test_gem_package_tar_reader_entry.rb
+++ b/test/rubygems/test_gem_package_tar_reader_entry.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/package/tar_test_case'
+require_relative 'package/tar_test_case'
 require 'rubygems/package'
 
 class TestGemPackageTarReaderEntry < Gem::Package::TarTestCase
diff --git a/test/rubygems/test_gem_package_tar_writer.rb b/test/rubygems/test_gem_package_tar_writer.rb
index 6260f80ef9..31a91fa21a 100644
--- a/test/rubygems/test_gem_package_tar_writer.rb
+++ b/test/rubygems/test_gem_package_tar_writer.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/package/tar_test_case'
+require_relative 'package/tar_test_case'
 require 'rubygems/package/tar_writer'
 
 class TestGemPackageTarWriter < Gem::Package::TarTestCase
diff --git a/test/rubygems/test_gem_package_task.rb b/test/rubygems/test_gem_package_task.rb
index 6f217061d2..0cedfe56eb 100644
--- a/test/rubygems/test_gem_package_task.rb
+++ b/test/rubygems/test_gem_package_task.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems'
 
 begin
diff --git a/test/rubygems/test_gem_path_support.rb b/test/rubygems/test_gem_path_support.rb
index 719aee52f6..88a3cc29b9 100644
--- a/test/rubygems/test_gem_path_support.rb
+++ b/test/rubygems/test_gem_path_support.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems'
 require 'fileutils'
 
diff --git a/test/rubygems/test_gem_platform.rb b/test/rubygems/test_gem_platform.rb
index 84754402ad..aae0250801 100644
--- a/test/rubygems/test_gem_platform.rb
+++ b/test/rubygems/test_gem_platform.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/platform'
 require 'rbconfig'
 
diff --git a/test/rubygems/test_gem_rdoc.rb b/test/rubygems/test_gem_rdoc.rb
index a8089bdb94..7b8ad07b27 100644
--- a/test/rubygems/test_gem_rdoc.rb
+++ b/test/rubygems/test_gem_rdoc.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 require 'rubygems'
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/rdoc'
 
 class TestGemRDoc < Gem::TestCase
diff --git a/test/rubygems/test_gem_remote_fetcher.rb b/test/rubygems/test_gem_remote_fetcher.rb
index 69f62b6ca4..1bae9247fe 100644
--- a/test/rubygems/test_gem_remote_fetcher.rb
+++ b/test/rubygems/test_gem_remote_fetcher.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 require 'webrick'
 require 'webrick/https' if Gem::HAVE_OPENSSL
diff --git a/test/rubygems/test_gem_request.rb b/test/rubygems/test_gem_request.rb
index 094d0aecf3..780150d639 100644
--- a/test/rubygems/test_gem_request.rb
+++ b/test/rubygems/test_gem_request.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/request'
 require 'ostruct'
 require 'base64'
diff --git a/test/rubygems/test_gem_request_connection_pools.rb b/test/rubygems/test_gem_request_connection_pools.rb
index a6ab002396..c5e7cf2ed4 100644
--- a/test/rubygems/test_gem_request_connection_pools.rb
+++ b/test/rubygems/test_gem_request_connection_pools.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/request'
 require 'timeout'
 
diff --git a/test/rubygems/test_gem_request_set.rb b/test/rubygems/test_gem_request_set.rb
index 404e9b61aa..e2fe98b9bf 100644
--- a/test/rubygems/test_gem_request_set.rb
+++ b/test/rubygems/test_gem_request_set.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/request_set'
 
 class TestGemRequestSet < Gem::TestCase
diff --git a/test/rubygems/test_gem_request_set_gem_dependency_api.rb b/test/rubygems/test_gem_request_set_gem_dependency_api.rb
index 5891882119..cc4f99df91 100644
--- a/test/rubygems/test_gem_request_set_gem_dependency_api.rb
+++ b/test/rubygems/test_gem_request_set_gem_dependency_api.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/request_set'
 
 class TestGemRequestSetGemDependencyAPI < Gem::TestCase
diff --git a/test/rubygems/test_gem_request_set_lockfile.rb b/test/rubygems/test_gem_request_set_lockfile.rb
index 2ad743c5a1..690b632d9b 100644
--- a/test/rubygems/test_gem_request_set_lockfile.rb
+++ b/test/rubygems/test_gem_request_set_lockfile.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/request_set'
 require 'rubygems/request_set/lockfile'
 
diff --git a/test/rubygems/test_gem_request_set_lockfile_parser.rb b/test/rubygems/test_gem_request_set_lockfile_parser.rb
index 2954df70d8..4007c3a69c 100644
--- a/test/rubygems/test_gem_request_set_lockfile_parser.rb
+++ b/test/rubygems/test_gem_request_set_lockfile_parser.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/request_set'
 require 'rubygems/request_set/lockfile'
 require 'rubygems/request_set/lockfile/tokenizer'
diff --git a/test/rubygems/test_gem_request_set_lockfile_tokenizer.rb b/test/rubygems/test_gem_request_set_lockfile_tokenizer.rb
index a81ecac7b7..f779c33012 100644
--- a/test/rubygems/test_gem_request_set_lockfile_tokenizer.rb
+++ b/test/rubygems/test_gem_request_set_lockfile_tokenizer.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/request_set'
 require 'rubygems/request_set/lockfile'
 require 'rubygems/request_set/lockfile/tokenizer'
diff --git a/test/rubygems/test_gem_requirement.rb b/test/rubygems/test_gem_requirement.rb
index f7cdbab92e..b20b3cc0dc 100644
--- a/test/rubygems/test_gem_requirement.rb
+++ b/test/rubygems/test_gem_requirement.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require "rubygems/requirement"
 
 class TestGemRequirement < Gem::TestCase
@@ -423,6 +423,40 @@ class TestGemRequirement < Gem::TestCase
     assert_requirement_hash_equal "1", "1.0.0"
   end
 
+  class Exploit < RuntimeError
+  end
+
+  def self.exploit(arg)
+    raise Exploit, "arg = #{arg}"
+  end
+
+  def test_marshal_load_attack
+    wa = Net::WriteAdapter.allocate
+    wa.instance_variable_set(:@socket, self.class)
+    wa.instance_variable_set(:@method_id, :exploit)
+    request_set = Gem::RequestSet.allocate
+    request_set.instance_variable_set(:@git_set, "id")
+    request_set.instance_variable_set(:@sets, wa)
+    wa = Net::WriteAdapter.allocate
+    wa.instance_variable_set(:@socket, request_set)
+    wa.instance_variable_set(:@method_id, :resolve)
+    ent = Gem::Package::TarReader::Entry.allocate
+    ent.instance_variable_set(:@read, 0)
+    ent.instance_variable_set(:@header, "aaa")
+    io = Net::BufferedIO.allocate
+    io.instance_variable_set(:@io, ent)
+    io.instance_variable_set(:@debug_output, wa)
+    reader = Gem::Package::TarReader.allocate
+    reader.instance_variable_set(:@io, io)
+    requirement = Gem::Requirement.allocate
+    requirement.instance_variable_set(:@requirements, reader)
+    m = [Gem::SpecFetcher, Gem::Installer, requirement]
+    e = assert_raise(TypeError) do
+      Marshal.load(Marshal.dump(m))
+    end
+    assert_equal(e.message, "wrong @requirements")
+  end
+
   # Assert that two requirements are equal. Handles Gem::Requirements,
   # strings, arrays, numbers, and versions.
 
diff --git a/test/rubygems/test_gem_resolver.rb b/test/rubygems/test_gem_resolver.rb
index fbf9438122..eb798ad557 100644
--- a/test/rubygems/test_gem_resolver.rb
+++ b/test/rubygems/test_gem_resolver.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestGemResolver < Gem::TestCase
   def setup
diff --git a/test/rubygems/test_gem_resolver_activation_request.rb b/test/rubygems/test_gem_resolver_activation_request.rb
index f973c5956d..c7b726a230 100644
--- a/test/rubygems/test_gem_resolver_activation_request.rb
+++ b/test/rubygems/test_gem_resolver_activation_request.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestGemResolverActivationRequest < Gem::TestCase
   def setup
diff --git a/test/rubygems/test_gem_resolver_api_set.rb b/test/rubygems/test_gem_resolver_api_set.rb
index aa17ec6f3a..c3db25d7aa 100644
--- a/test/rubygems/test_gem_resolver_api_set.rb
+++ b/test/rubygems/test_gem_resolver_api_set.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestGemResolverAPISet < Gem::TestCase
   def setup
diff --git a/test/rubygems/test_gem_resolver_api_specification.rb b/test/rubygems/test_gem_resolver_api_specification.rb
index e9ba4ae481..3f9b81868f 100644
--- a/test/rubygems/test_gem_resolver_api_specification.rb
+++ b/test/rubygems/test_gem_resolver_api_specification.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestGemResolverAPISpecification < Gem::TestCase
   def test_initialize
diff --git a/test/rubygems/test_gem_resolver_best_set.rb b/test/rubygems/test_gem_resolver_best_set.rb
index df6b438763..0e279d16a8 100644
--- a/test/rubygems/test_gem_resolver_best_set.rb
+++ b/test/rubygems/test_gem_resolver_best_set.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestGemResolverBestSet < Gem::TestCase
   def setup
diff --git a/test/rubygems/test_gem_resolver_composed_set.rb b/test/rubygems/test_gem_resolver_composed_set.rb
index 7c8ae004a3..405753a373 100644
--- a/test/rubygems/test_gem_resolver_composed_set.rb
+++ b/test/rubygems/test_gem_resolver_composed_set.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestGemResolverComposedSet < Gem::TestCase
   def test_errors
diff --git a/test/rubygems/test_gem_resolver_conflict.rb b/test/rubygems/test_gem_resolver_conflict.rb
index ff5fe9bae3..1d46e69c3f 100644
--- a/test/rubygems/test_gem_resolver_conflict.rb
+++ b/test/rubygems/test_gem_resolver_conflict.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestGemResolverConflict < Gem::TestCase
   def test_explanation
diff --git a/test/rubygems/test_gem_resolver_dependency_request.rb b/test/rubygems/test_gem_resolver_dependency_request.rb
index a8ddc8362b..cea0a7952d 100644
--- a/test/rubygems/test_gem_resolver_dependency_request.rb
+++ b/test/rubygems/test_gem_resolver_dependency_request.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestGemResolverDependencyRequest < Gem::TestCase
   def setup
diff --git a/test/rubygems/test_gem_resolver_git_set.rb b/test/rubygems/test_gem_resolver_git_set.rb
index 7b0efa0680..145cd6c7df 100644
--- a/test/rubygems/test_gem_resolver_git_set.rb
+++ b/test/rubygems/test_gem_resolver_git_set.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestGemResolverGitSet < Gem::TestCase
   def setup
diff --git a/test/rubygems/test_gem_resolver_git_specification.rb b/test/rubygems/test_gem_resolver_git_specification.rb
index 25e93bb7d5..857452c159 100644
--- a/test/rubygems/test_gem_resolver_git_specification.rb
+++ b/test/rubygems/test_gem_resolver_git_specification.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/installer'
 
 class TestGemResolverGitSpecification < Gem::TestCase
@@ -63,6 +63,7 @@ class TestGemResolverGitSpecification < Gem::TestCase
 
   def test_install_extension
     pend if Gem.java_platform?
+    pend if /mswin/ =~ RUBY_PLATFORM && ENV.key?('GITHUB_ACTIONS') # not working from the beginning
     name, _, repository, = git_gem 'a', 1 do |s|
       s.extensions << 'ext/extconf.rb'
     end
diff --git a/test/rubygems/test_gem_resolver_index_set.rb b/test/rubygems/test_gem_resolver_index_set.rb
index 2de766f60a..ddae0c2b82 100644
--- a/test/rubygems/test_gem_resolver_index_set.rb
+++ b/test/rubygems/test_gem_resolver_index_set.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestGemResolverIndexSet < Gem::TestCase
   def setup
diff --git a/test/rubygems/test_gem_resolver_index_specification.rb b/test/rubygems/test_gem_resolver_index_specification.rb
index 382f95c004..ef9c17034e 100644
--- a/test/rubygems/test_gem_resolver_index_specification.rb
+++ b/test/rubygems/test_gem_resolver_index_specification.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/available_set'
 
 class TestGemResolverIndexSpecification < Gem::TestCase
diff --git a/test/rubygems/test_gem_resolver_installed_specification.rb b/test/rubygems/test_gem_resolver_installed_specification.rb
index b102f98d00..0e5ea02fb9 100644
--- a/test/rubygems/test_gem_resolver_installed_specification.rb
+++ b/test/rubygems/test_gem_resolver_installed_specification.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestGemResolverInstalledSpecification < Gem::TestCase
   def setup
diff --git a/test/rubygems/test_gem_resolver_installer_set.rb b/test/rubygems/test_gem_resolver_installer_set.rb
index d45a527d2f..66857943c9 100644
--- a/test/rubygems/test_gem_resolver_installer_set.rb
+++ b/test/rubygems/test_gem_resolver_installer_set.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestGemResolverInstallerSet < Gem::TestCase
   def test_add_always_install
diff --git a/test/rubygems/test_gem_resolver_local_specification.rb b/test/rubygems/test_gem_resolver_local_specification.rb
index 67b8f34cc1..c11f736128 100644
--- a/test/rubygems/test_gem_resolver_local_specification.rb
+++ b/test/rubygems/test_gem_resolver_local_specification.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/available_set'
 
 class TestGemResolverLocalSpecification < Gem::TestCase
diff --git a/test/rubygems/test_gem_resolver_lock_set.rb b/test/rubygems/test_gem_resolver_lock_set.rb
index cb03e0b5f8..dc7767a3f8 100644
--- a/test/rubygems/test_gem_resolver_lock_set.rb
+++ b/test/rubygems/test_gem_resolver_lock_set.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestGemResolverLockSet < Gem::TestCase
   def setup
diff --git a/test/rubygems/test_gem_resolver_lock_specification.rb b/test/rubygems/test_gem_resolver_lock_specification.rb
index 07654a9164..46c8e5edd6 100644
--- a/test/rubygems/test_gem_resolver_lock_specification.rb
+++ b/test/rubygems/test_gem_resolver_lock_specification.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/installer'
 require 'rubygems/resolver'
 
diff --git a/test/rubygems/test_gem_resolver_requirement_list.rb b/test/rubygems/test_gem_resolver_requirement_list.rb
index af8a77ef4b..806c387669 100644
--- a/test/rubygems/test_gem_resolver_requirement_list.rb
+++ b/test/rubygems/test_gem_resolver_requirement_list.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestGemResolverRequirementList < Gem::TestCase
   def setup
diff --git a/test/rubygems/test_gem_resolver_specification.rb b/test/rubygems/test_gem_resolver_specification.rb
index 8b50bf91bd..9f28c1c0cf 100644
--- a/test/rubygems/test_gem_resolver_specification.rb
+++ b/test/rubygems/test_gem_resolver_specification.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestGemResolverSpecification < Gem::TestCase
   class TestSpec < Gem::Resolver::Specification
diff --git a/test/rubygems/test_gem_resolver_vendor_set.rb b/test/rubygems/test_gem_resolver_vendor_set.rb
index 19cc7383c6..e16d43ac1a 100644
--- a/test/rubygems/test_gem_resolver_vendor_set.rb
+++ b/test/rubygems/test_gem_resolver_vendor_set.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestGemResolverVendorSet < Gem::TestCase
   def setup
diff --git a/test/rubygems/test_gem_resolver_vendor_specification.rb b/test/rubygems/test_gem_resolver_vendor_specification.rb
index dbf0c58e0b..93382ccd81 100644
--- a/test/rubygems/test_gem_resolver_vendor_specification.rb
+++ b/test/rubygems/test_gem_resolver_vendor_specification.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestGemResolverVendorSpecification < Gem::TestCase
   def setup
diff --git a/test/rubygems/test_gem_security.rb b/test/rubygems/test_gem_security.rb
index 0badb96763..2eabbea3bf 100644
--- a/test/rubygems/test_gem_security.rb
+++ b/test/rubygems/test_gem_security.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/security'
 
 unless Gem::HAVE_OPENSSL
diff --git a/test/rubygems/test_gem_security_policy.rb b/test/rubygems/test_gem_security_policy.rb
index a85791c918..515b8ea00b 100644
--- a/test/rubygems/test_gem_security_policy.rb
+++ b/test/rubygems/test_gem_security_policy.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-require 'rubygems/test_case'
+require_relative 'helper'
 
 unless Gem::HAVE_OPENSSL
   warn 'Skipping Gem::Security::Policy tests.  openssl not found.'
diff --git a/test/rubygems/test_gem_security_signer.rb b/test/rubygems/test_gem_security_signer.rb
index 9a369a2518..7bd6510b50 100644
--- a/test/rubygems/test_gem_security_signer.rb
+++ b/test/rubygems/test_gem_security_signer.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 unless Gem::HAVE_OPENSSL
   warn 'Skipping Gem::Security::Signer tests.  openssl not found.'
diff --git a/test/rubygems/test_gem_security_trust_dir.rb b/test/rubygems/test_gem_security_trust_dir.rb
index 6dc0997eaf..fc88c84865 100644
--- a/test/rubygems/test_gem_security_trust_dir.rb
+++ b/test/rubygems/test_gem_security_trust_dir.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 unless Gem::HAVE_OPENSSL
   warn 'Skipping Gem::Security::TrustDir tests.  openssl not found.'
diff --git a/test/rubygems/test_gem_server.rb b/test/rubygems/test_gem_server.rb
index aeb7fa2ab9..f6aa99fb02 100644
--- a/test/rubygems/test_gem_server.rb
+++ b/test/rubygems/test_gem_server.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/server'
 require 'stringio'
 
diff --git a/test/rubygems/test_gem_silent_ui.rb b/test/rubygems/test_gem_silent_ui.rb
index 0d46ab592a..355255fb48 100644
--- a/test/rubygems/test_gem_silent_ui.rb
+++ b/test/rubygems/test_gem_silent_ui.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/user_interaction'
 require 'timeout'
 
diff --git a/test/rubygems/test_gem_source.rb b/test/rubygems/test_gem_source.rb
index f7b288ae11..24312626f4 100644
--- a/test/rubygems/test_gem_source.rb
+++ b/test/rubygems/test_gem_source.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/source'
 require 'rubygems/indexer'
 
diff --git a/test/rubygems/test_gem_source_fetch_problem.rb b/test/rubygems/test_gem_source_fetch_problem.rb
index 87b190a12c..0b1472c0c6 100644
--- a/test/rubygems/test_gem_source_fetch_problem.rb
+++ b/test/rubygems/test_gem_source_fetch_problem.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestGemSourceFetchProblem < Gem::TestCase
   def test_exception
diff --git a/test/rubygems/test_gem_source_git.rb b/test/rubygems/test_gem_source_git.rb
index 749859b024..73ed8dd2ef 100644
--- a/test/rubygems/test_gem_source_git.rb
+++ b/test/rubygems/test_gem_source_git.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/source'
 
 class TestGemSourceGit < Gem::TestCase
diff --git a/test/rubygems/test_gem_source_installed.rb b/test/rubygems/test_gem_source_installed.rb
index 93aa4eb039..ef9b63e611 100644
--- a/test/rubygems/test_gem_source_installed.rb
+++ b/test/rubygems/test_gem_source_installed.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/source'
 
 class TestGemSourceInstalled < Gem::TestCase
diff --git a/test/rubygems/test_gem_source_list.rb b/test/rubygems/test_gem_source_list.rb
index 7c60af3ff8..6ac5dbb2a6 100644
--- a/test/rubygems/test_gem_source_list.rb
+++ b/test/rubygems/test_gem_source_list.rb
@@ -1,7 +1,7 @@
 # frozen_string_literal: true
 require 'rubygems'
 require 'rubygems/source_list'
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestGemSourceList < Gem::TestCase
   def setup
diff --git a/test/rubygems/test_gem_source_local.rb b/test/rubygems/test_gem_source_local.rb
index 7417f8d111..2d4ddbc3a4 100644
--- a/test/rubygems/test_gem_source_local.rb
+++ b/test/rubygems/test_gem_source_local.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/source'
 
 require 'fileutils'
diff --git a/test/rubygems/test_gem_source_lock.rb b/test/rubygems/test_gem_source_lock.rb
index 8c55926d94..5f916cdf7f 100644
--- a/test/rubygems/test_gem_source_lock.rb
+++ b/test/rubygems/test_gem_source_lock.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestGemSourceLock < Gem::TestCase
   def test_fetch_spec
diff --git a/test/rubygems/test_gem_source_specific_file.rb b/test/rubygems/test_gem_source_specific_file.rb
index f6d6aa51d5..72ed993a88 100644
--- a/test/rubygems/test_gem_source_specific_file.rb
+++ b/test/rubygems/test_gem_source_specific_file.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/source'
 
 class TestGemSourceSpecificFile < Gem::TestCase
diff --git a/test/rubygems/test_gem_source_subpath_problem.rb b/test/rubygems/test_gem_source_subpath_problem.rb
index b2289ea625..c37df39f0c 100644
--- a/test/rubygems/test_gem_source_subpath_problem.rb
+++ b/test/rubygems/test_gem_source_subpath_problem.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/source'
 
 class TestGemSourceSubpathProblem < Gem::TestCase
diff --git a/test/rubygems/test_gem_source_vendor.rb b/test/rubygems/test_gem_source_vendor.rb
index 18a3f47f45..a5ffb0f223 100644
--- a/test/rubygems/test_gem_source_vendor.rb
+++ b/test/rubygems/test_gem_source_vendor.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/source'
 
 class TestGemSourceVendor < Gem::TestCase
diff --git a/test/rubygems/test_gem_spec_fetcher.rb b/test/rubygems/test_gem_spec_fetcher.rb
index 8b94708259..afae46e120 100644
--- a/test/rubygems/test_gem_spec_fetcher.rb
+++ b/test/rubygems/test_gem_spec_fetcher.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/spec_fetcher'
 
 class TestGemSpecFetcher < Gem::TestCase
diff --git a/test/rubygems/test_gem_specification.rb b/test/rubygems/test_gem_specification.rb
index 226ec40bf0..88afa3faa0 100644
--- a/test/rubygems/test_gem_specification.rb
+++ b/test/rubygems/test_gem_specification.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 require 'benchmark'
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'date'
 require 'pathname'
 require 'stringio'
@@ -107,8 +107,6 @@ end
     end
 
     @current_version = Gem::Specification::CURRENT_SPECIFICATION_VERSION
-
-    load 'rubygems/syck_hack.rb'
   end
 
   def test_self_find_active_stub_by_path
@@ -747,125 +745,6 @@ end
                  spec.specification_version
   end
 
-  def test_self_from_yaml_syck_date_bug
-    # This is equivalent to (and totally valid) psych 1.0 output and
-    # causes parse errors on syck.
-    yaml = @a1.to_yaml
-    yaml.sub!(/^date:.*/, "date: 2011-04-26 00:00:00.000000000Z")
-
-    spec = with_syck do
-      Gem::Specification.from_yaml yaml
-    end
-
-    assert_kind_of Time, @a1.date
-    assert_kind_of Time, spec.date
-  end
-
-  def test_self_from_yaml_syck_default_key_bug
-    # This is equivalent to (and totally valid) psych 1.0 output and
-    # causes parse errors on syck.
-    yaml = <<-YAML
---- !ruby/object:Gem::Specification
-name: posix-spawn
-version: !ruby/object:Gem::Version
-  version: 0.3.6
-  prerelease:
-dependencies:
-- !ruby/object:Gem::Dependency
-  name: rake-compiler
-  requirement: &70243867725240 !ruby/object:Gem::Requirement
-    none: false
-    requirements:
-    - - =
-      - !ruby/object:Gem::Version
-        version: 0.7.6
-  type: :development
-  prerelease: false
-  version_requirements: *70243867725240
-platform: ruby
-files: []
-test_files: []
-bindir:
-    YAML
-
-    spec = with_syck do
-      Gem::Specification.from_yaml yaml
-    end
-
-    op = spec.dependencies.first.requirement.requirements.first.first
-    refute_kind_of YAML::Syck::DefaultKey, op
-
-    refute_match %r{DefaultKey}, spec.to_ruby
-  end
-
-  def test_self_from_yaml_cleans_up_defaultkey
-    yaml = <<-YAML
---- !ruby/object:Gem::Specification
-name: posix-spawn
-version: !ruby/object:Gem::Version
-  version: 0.3.6
-  prerelease:
-dependencies:
-- !ruby/object:Gem::Dependency
-  name: rake-compiler
-  requirement: &70243867725240 !ruby/object:Gem::Requirement
-    none: false
-    requirements:
-    - - !ruby/object:YAML::Syck::DefaultKey {}
-
-      - !ruby/object:Gem::Version
-        version: 0.7.6
-  type: :development
-  prerelease: false
-  version_requirements: *70243867725240
-platform: ruby
-files: []
-test_files: []
-bindir:
-    YAML
-
-    spec = Gem::Specification.from_yaml yaml
-
-    op = spec.dependencies.first.requirement.requirements.first.first
-    refute_kind_of YAML::Syck::DefaultKey, op
-
-    refute_match %r{DefaultKey}, spec.to_ruby
-  end
-
-  def test_self_from_yaml_cleans_up_defaultkey_from_newer_192
-    yaml = <<-YAML
---- !ruby/object:Gem::Specification
-name: posix-spawn
-version: !ruby/object:Gem::Version
-  version: 0.3.6
-  prerelease:
-dependencies:
-- !ruby/object:Gem::Dependency
-  name: rake-compiler
-  requirement: &70243867725240 !ruby/object:Gem::Requirement
-    none: false
-    requirements:
-    - - !ruby/object:Syck::DefaultKey {}
-
-      - !ruby/object:Gem::Version
-        version: 0.7.6
-  type: :development
-  prerelease: false
-  version_requirements: *70243867725240
-platform: ruby
-files: []
-test_files: []
-bindir:
-    YAML
-
-    spec = Gem::Specification.from_yaml yaml
-
-    op = spec.dependencies.first.requirement.requirements.first.first
-    refute_kind_of YAML::Syck::DefaultKey, op
-
-    refute_match %r{DefaultKey}, spec.to_ruby
-  end
-
   def test_self_from_yaml_cleans_up_Date_objects
     yaml = <<-YAML
 --- !ruby/object:Gem::Specification
@@ -3860,49 +3739,6 @@ end
     end
   end
 
-  def with_syck
-    begin
-      verbose, $VERBOSE = $VERBOSE, nil
-      require "yaml"
-      old_engine = YAML::ENGINE.yamler
-      YAML::ENGINE.yamler = 'syck'
-      load 'rubygems/syck_hack.rb'
-    rescue NameError
-      # probably on 1.8, ignore
-    ensure
-      $VERBOSE = verbose
-    end
-
-    yield
-  ensure
-    begin
-      YAML::ENGINE.yamler = old_engine
-      load 'rubygems/syck_hack.rb'
-    rescue NameError
-      # ignore
-    end
-  end
-
-  def with_psych
-    begin
-      require "yaml"
-      old_engine = YAML::ENGINE.yamler
-      YAML::ENGINE.yamler = 'psych'
-      load 'rubygems/syck_hack.rb'
-    rescue NameError
-      # probably on 1.8, ignore
-    end
-
-    yield
-  ensure
-    begin
-      YAML::ENGINE.yamler = old_engine
-      load 'rubygems/syck_hack.rb'
-    rescue NameError
-      # ignore
-    end
-  end
-
   def silence_warnings
     old_verbose, $VERBOSE = $VERBOSE, false
     yield
diff --git a/test/rubygems/test_gem_stream_ui.rb b/test/rubygems/test_gem_stream_ui.rb
index 9148ad1385..dc245c342a 100644
--- a/test/rubygems/test_gem_stream_ui.rb
+++ b/test/rubygems/test_gem_stream_ui.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/user_interaction'
 require 'timeout'
 
diff --git a/test/rubygems/test_gem_stub_specification.rb b/test/rubygems/test_gem_stub_specification.rb
index 4f2e40dde0..e008391ef7 100644
--- a/test/rubygems/test_gem_stub_specification.rb
+++ b/test/rubygems/test_gem_stub_specification.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require "rubygems/test_case"
+require_relative "helper"
 require "rubygems/stub_specification"
 
 class TestStubSpecification < Gem::TestCase
diff --git a/test/rubygems/test_gem_text.rb b/test/rubygems/test_gem_text.rb
index d8e4b75f3a..069cfdc4e6 100644
--- a/test/rubygems/test_gem_text.rb
+++ b/test/rubygems/test_gem_text.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require "rubygems/text"
 
 class TestGemText < Gem::TestCase
diff --git a/test/rubygems/test_gem_uninstaller.rb b/test/rubygems/test_gem_uninstaller.rb
index 0386099a8f..9e18972864 100644
--- a/test/rubygems/test_gem_uninstaller.rb
+++ b/test/rubygems/test_gem_uninstaller.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/installer_test_case'
+require_relative 'installer_test_case'
 require 'rubygems/uninstaller'
 
 class TestGemUninstaller < Gem::InstallerTestCase
diff --git a/test/rubygems/test_gem_unsatisfiable_dependency_error.rb b/test/rubygems/test_gem_unsatisfiable_dependency_error.rb
index 7950efb2a9..f9d30123f0 100644
--- a/test/rubygems/test_gem_unsatisfiable_dependency_error.rb
+++ b/test/rubygems/test_gem_unsatisfiable_dependency_error.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestGemUnsatisfiableDependencyError < Gem::TestCase
   def setup
diff --git a/test/rubygems/test_gem_uri_formatter.rb b/test/rubygems/test_gem_uri_formatter.rb
index debc7739cb..a41c9238ad 100644
--- a/test/rubygems/test_gem_uri_formatter.rb
+++ b/test/rubygems/test_gem_uri_formatter.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/uri_formatter'
 
 class TestGemUriFormatter < Gem::TestCase
diff --git a/test/rubygems/test_gem_util.rb b/test/rubygems/test_gem_util.rb
index 69b7043328..e0db5c283d 100644
--- a/test/rubygems/test_gem_util.rb
+++ b/test/rubygems/test_gem_util.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/util'
 
 class TestGemUtil < Gem::TestCase
diff --git a/test/rubygems/test_gem_validator.rb b/test/rubygems/test_gem_validator.rb
index 5158543fa9..8090776b4a 100644
--- a/test/rubygems/test_gem_validator.rb
+++ b/test/rubygems/test_gem_validator.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-require "rubygems/test_case"
+require_relative "helper"
 require "rubygems/validator"
 
 class TestGemValidator < Gem::TestCase
diff --git a/test/rubygems/test_gem_version.rb b/test/rubygems/test_gem_version.rb
index 91325c2214..422e1ee86c 100644
--- a/test/rubygems/test_gem_version.rb
+++ b/test/rubygems/test_gem_version.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require "rubygems/version"
 
 class TestGemVersion < Gem::TestCase
diff --git a/test/rubygems/test_gem_version_option.rb b/test/rubygems/test_gem_version_option.rb
index 49a8513dbe..74d7979e3a 100644
--- a/test/rubygems/test_gem_version_option.rb
+++ b/test/rubygems/test_gem_version_option.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems/command'
 require 'rubygems/version_option'
 
diff --git a/test/rubygems/test_kernel.rb b/test/rubygems/test_kernel.rb
index b7c809f87d..dee36d05ee 100644
--- a/test/rubygems/test_kernel.rb
+++ b/test/rubygems/test_kernel.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestKernel < Gem::TestCase
   def setup
diff --git a/test/rubygems/test_project_sanity.rb b/test/rubygems/test_project_sanity.rb
index 97fc64fb6a..e9e3bfd1ba 100644
--- a/test/rubygems/test_project_sanity.rb
+++ b/test/rubygems/test_project_sanity.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-require "rubygems/test_case"
+require_relative "helper"
 require "open3"
 
 class TestProjectSanity < Gem::TestCase
diff --git a/test/rubygems/test_remote_fetch_error.rb b/test/rubygems/test_remote_fetch_error.rb
index a1c25bcdda..b9e58389d3 100644
--- a/test/rubygems/test_remote_fetch_error.rb
+++ b/test/rubygems/test_remote_fetch_error.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 
 class TestRemoteFetchError < Gem::TestCase
   def test_password_redacted
diff --git a/test/rubygems/test_require.rb b/test/rubygems/test_require.rb
index 4591530156..07e412cc76 100644
--- a/test/rubygems/test_require.rb
+++ b/test/rubygems/test_require.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'rubygems/test_case'
+require_relative 'helper'
 require 'rubygems'
 
 class TestGemRequire < Gem::TestCase
diff --git a/test/rubygems/utilities.rb b/test/rubygems/utilities.rb
new file mode 100644
index 0000000000..20416fe70b
--- /dev/null
+++ b/test/rubygems/utilities.rb
@@ -0,0 +1,371 @@
+# frozen_string_literal: true
+require 'tempfile'
+require 'rubygems'
+require 'rubygems/remote_fetcher'
+
+##
+# A fake Gem::RemoteFetcher for use in tests or to avoid real live HTTP
+# requests when testing code that uses RubyGems.
+#
+# Example:
+#
+#   @fetcher = Gem::FakeFetcher.new
+#   @fetcher.data['http://gems.example.com/yaml'] = source_index.to_yaml
+#   Gem::RemoteFetcher.fetcher = @fetcher
+#
+#   use nested array if multiple response is needed
+#
+#   @fetcher.data['http://gems.example.com/sequence'] = [['Success', 200, 'OK'], ['Failed', 401, 'Unauthorized']]
+#
+#   @fetcher.fetch_path('http://gems.example.com/sequence') # => ['Success', 200, 'OK']
+#   @fetcher.fetch_path('http://gems.example.com/sequence') # => ['Failed', 401, 'Unauthorized']
+#
+#   # invoke RubyGems code
+#
+#   paths = @fetcher.paths
+#   assert_equal 'http://gems.example.com/yaml', paths.shift
+#   assert paths.empty?, paths.join(', ')
+#
+# See RubyGems' tests for more examples of FakeFetcher.
+
+class Gem::FakeFetcher
+  attr_reader :data
+  attr_reader :last_request
+  attr_accessor :paths
+
+  def initialize
+    @data = {}
+    @paths = []
+  end
+
+  def find_data(path)
+    return Gem.read_binary path.path if URI === path and 'file' == path.scheme
+
+    if URI === path and "URI::#{path.scheme.upcase}" != path.class.name
+      raise ArgumentError,
+        "mismatch for scheme #{path.scheme} and class #{path.class}"
+    end
+
+    path = path.to_s
+    @paths << path
+    raise ArgumentError, 'need full URI' unless path.start_with?("https://", "http://")
+
+    unless @data.key? path
+      raise Gem::RemoteFetcher::FetchError.new("no data for #{path}", path)
+    end
+
+    if @data[path].kind_of?(Array) && @data[path].first.kind_of?(Array)
+      @data[path].shift
+    else
+      @data[path]
+    end
+  end
+
+  def fetch_path(path, mtime = nil, head = false)
+    data = find_data(path)
+
+    if data.respond_to?(:call)
+      data.call
+    else
+      if path.to_s.end_with?(".gz") and not data.nil? and not data.empty?
+        data = Gem::Util.gunzip data
+      end
+      data
+    end
+  end
+
+  def cache_update_path(uri, path = nil, update = true)
+    if data = fetch_path(uri)
+      File.open(path, 'wb') {|io| io.write data } if path and update
+      data
+    else
+      Gem.read_binary(path) if path
+    end
+  end
+
+  # Thanks, FakeWeb!
+  def open_uri_or_path(path)
+    data = find_data(path)
+    body, code, msg = data
+
+    response = Net::HTTPResponse.send(:response_class, code.to_s).new("1.0", code.to_s, msg)
+    response.instance_variable_set(:@body, body)
+    response.instance_variable_set(:@read, true)
+    response
+  end
+
+  def request(uri, request_class, last_modified = nil)
+    data = find_data(uri)
+    body, code, msg = (data.respond_to?(:call) ? data.call : data)
+
+    @last_request = request_class.new uri.request_uri
+    yield @last_request if block_given?
+
+    response = Net::HTTPResponse.send(:response_class, code.to_s).new("1.0", code.to_s, msg)
+    response.instance_variable_set(:@body, body)
+    response.instance_variable_set(:@read, true)
+    response
+  end
+
+  def pretty_print(q) # :nodoc:
+    q.group 2, '[FakeFetcher', ']' do
+      q.breakable
+      q.text 'URIs:'
+
+      q.breakable
+      q.pp @data.keys
+    end
+  end
+
+  def fetch_size(path)
+    path = path.to_s
+    @paths << path
+
+    raise ArgumentError, 'need full URI' unless path =~ %r{^http://}
+
+    unless @data.key? path
+      raise Gem::RemoteFetcher::FetchError.new("no data for #{path}", path)
+    end
+
+    data = @data[path]
+
+    data.respond_to?(:call) ? data.call : data.length
+  end
+
+  def download(spec, source_uri, install_dir = Gem.dir)
+    name = File.basename spec.cache_file
+    path = if Dir.pwd == install_dir # see fetch_command
+             install_dir
+           else
+             File.join install_dir, "cache"
+           end
+
+    path = File.join path, name
+
+    if source_uri =~ /^http/
+      File.open(path, "wb") do |f|
+        f.write fetch_path(File.join(source_uri, "gems", name))
+      end
+    else
+      FileUtils.cp source_uri, path
+    end
+
+    path
+  end
+
+  def download_to_cache(dependency)
+    found, _ = Gem::SpecFetcher.fetcher.spec_for_dependency dependency
+
+    return if found.empty?
+
+    spec, source = found.first
+
+    download spec, source.uri.to_s
+  end
+end
+
+# :stopdoc:
+class Gem::RemoteFetcher
+  def self.fetcher=(fetcher)
+    @fetcher = fetcher
+  end
+end
+# :startdoc:
+
+##
+# The SpecFetcherSetup allows easy setup of a remote source in RubyGems tests:
+#
+#   spec_fetcher do |f|
+#     f.gem  'a', 1
+#     f.spec 'a', 2
+#     f.gem  'b', 1' 'a' => '~> 1.0'
+#   end
+#
+# The above declaration creates two gems, a-1 and b-1, with a dependency from
+# b to a.  The declaration creates an additional spec a-2, but no gem for it
+# (so it cannot be installed).
+#
+# After the gems are created they are removed from Gem.dir.
+
+class Gem::TestCase::SpecFetcherSetup
+  ##
+  # Executes a SpecFetcher setup block.  Yields an instance then creates the
+  # gems and specifications defined in the instance.
+
+  def self.declare(test, repository)
+    setup = new test, repository
+
+    yield setup
+
+    setup.execute
+  end
+
+  def initialize(test, repository) # :nodoc:
+    @test       = test
+    @repository = repository
+
+    @gems       = {}
+    @downloaded = []
+    @installed  = []
+    @operations = []
+  end
+
+  ##
+  # Returns a Hash of created Specification full names and the corresponding
+  # Specification.
+
+  def created_specs
+    created = {}
+
+    @gems.keys.each do |spec|
+      created[spec.full_name] = spec
+    end
+
+    created
+  end
+
+  ##
+  # Creates any defined gems or specifications
+
+  def execute # :nodoc:
+    execute_operations
+
+    setup_fetcher
+
+    created_specs
+  end
+
+  def execute_operations # :nodoc:
+    @operations.each do |operation, *arguments|
+      block = arguments.pop
+      case operation
+      when :gem then
+        spec, gem = @test.util_gem(*arguments, &block)
+
+        write_spec spec
+
+        @gems[spec] = gem
+        @installed << spec
+      when :download then
+        spec, gem = @test.util_gem(*arguments, &block)
+
+        @gems[spec] = gem
+        @downloaded << spec
+      when :spec then
+        spec = @test.util_spec(*arguments, &block)
+
+        write_spec spec
+
+        @gems[spec] = nil
+        @installed << spec
+      end
+    end
+  end
+
+  ##
+  # Creates a gem with +name+, +version+ and +deps+.  The created gem can be
+  # downloaded and installed.
+  #
+  # The specification will be yielded before gem creation for customization,
+  # but only the block or the dependencies may be set, not both.
+
+  def gem(name, version, dependencies = nil, &block)
+    @operations << [:gem, name, version, dependencies, block]
+  end
+
+  ##
+  # Creates a gem with +name+, +version+ and +deps+.  The created gem is
+  # downloaded in to the cache directory but is not installed
+  #
+  # The specification will be yielded before gem creation for customization,
+  # but only the block or the dependencies may be set, not both.
+
+  def download(name, version, dependencies = nil, &block)
+    @operations << [:download, name, version, dependencies, block]
+  end
+
+  ##
+  # Creates a legacy platform spec with the name 'pl' and version 1
+
+  def legacy_platform
+    spec 'pl', 1 do |s|
+      s.platform = Gem::Platform.new 'i386-linux'
+      s.instance_variable_set :@original_platform, 'i386-linux'
+    end
+  end
+
+  def setup_fetcher # :nodoc:
+    require 'zlib'
+    require 'socket'
+    require 'rubygems/remote_fetcher'
+
+    unless @test.fetcher
+      @test.fetcher = Gem::FakeFetcher.new
+      Gem::RemoteFetcher.fetcher = @test.fetcher
+    end
+
+    Gem::Specification.reset
+
+    begin
+      gem_repo, @test.gem_repo = @test.gem_repo, @repository
+      @test.uri = URI @repository
+
+      @test.util_setup_spec_fetcher(*@downloaded)
+    ensure
+      @test.gem_repo = gem_repo
+      @test.uri = URI gem_repo
+    end
+
+    @gems.each do |spec, gem|
+      next unless gem
+
+      @test.fetcher.data["#{@repository}gems/#{spec.file_name}"] =
+        Gem.read_binary(gem)
+
+      FileUtils.cp gem, spec.cache_file
+    end
+  end
+
+  ##
+  # Creates a spec with +name+, +version+ and +deps+.  The created gem can be
+  # downloaded and installed.
+  #
+  # The specification will be yielded before creation for customization,
+  # but only the block or the dependencies may be set, not both.
+
+  def spec(name, version, dependencies = nil, &block)
+    @operations << [:spec, name, version, dependencies, block]
+  end
+
+  def write_spec(spec) # :nodoc:
+    File.open spec.spec_file, 'w' do |io|
+      io.write spec.to_ruby_for_cache
+    end
+  end
+end
+
+##
+# A StringIO duck-typed class that uses Tempfile instead of String as the
+# backing store.
+#
+# This class was added to flush out problems in Rubinius' IO implementation.
+
+class TempIO < Tempfile
+  ##
+  # Creates a new TempIO that will be initialized to contain +string+.
+
+  def initialize(string = '')
+    super "TempIO"
+    binmode
+    write string
+    rewind
+  end
+
+  ##
+  # The content of the TempIO as a String.
+
+  def string
+    flush
+    Gem.read_binary path
+  end
+end