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Module: Gem

Relationships & Source Files
Namespace Children
Modules:
Classes:
Exceptions:
Defined in: lib/rubygems.rb,
lib/rubygems.rb,
lib/rubygems/compatibility.rb,
lib/rubygems/defaults.rb,
lib/rubygems/errors.rb,
lib/rubygems/openssl.rb,
lib/rubygems/psych_tree.rb,
lib/rubygems/safe_yaml.rb,
lib/rubygems/tsort/lib/tsort.rb,
lib/rubygems/util/list.rb

Overview

RubyGems is the Ruby standard for publishing and managing third party libraries.

For user documentation, see:

For gem developer documentation see:

Further RubyGems documentation can be found at:

RubyGems Plugins

RubyGems will load plugins in the latest version of each installed gem or $LOAD_PATH. Plugins must be named ‘rubygems_plugin’ (.rb, .so, etc) and placed at the root of your gem’s #require_path. Plugins are installed at a special location and loaded on boot.

For an example plugin, see the Graph gem which adds a gem graph command.

RubyGems Defaults, Packaging

RubyGems defaults are stored in lib/rubygems/defaults.rb. If you’re packaging RubyGems or implementing Ruby you can change RubyGems’ defaults.

For RubyGems packagers, provide lib/rubygems/defaults/operating_system.rb and override any defaults from lib/rubygems/defaults.rb.

For Ruby implementers, provide lib/rubygems/defaults/#RUBY_ENGINE.rb and override any defaults from lib/rubygems/defaults.rb.

If you need RubyGems to perform extra work on install or uninstall, your defaults override file can set pre/post install and uninstall hooks. See .pre_install, .pre_uninstall, .post_install, .post_uninstall.

Bugs

You can submit bugs to the Rubys bug tracker on GitHub

Credits

RubyGems is currently maintained by Eric Hodel.

RubyGems was originally developed at RubyConf 2003 by:

  • Rich Kilmer – rich(at)infoether.com

  • Chad Fowler – chad(at)chadfowler.com

  • David Black – dblack(at)wobblini.net

  • Paul Brannan – paul(at)atdesk.com

  • Jim Weirich – jim(at)weirichhouse.org

Contributors:

  • Gavin Sinclair – gsinclair(at)soyabean.com.au

  • George Marrows – george.marrows(at)ntlworld.com

  • Dick Davies – rasputnik(at)hellooperator.net

  • Mauricio Fernandez – batsman.geo(at)yahoo.com

  • Simon Strandgaard – neoneye(at)adslhome.dk

  • Dave Glasser – glasser(at)mit.edu

  • Paul Duncan – pabs(at)pablotron.org

  • Ville Aine – vaine(at)cs.helsinki.fi

  • Eric Hodel – drbrain(at)segment7.net

  • Daniel Berger – djberg96(at)gmail.com

  • Phil Hagelberg – technomancy(at)gmail.com

  • Ryan Davis – ryand-ruby(at)zenspider.com

  • Evan Phoenix – evan(at)fallingsnow.net

  • Steve Klabnik – steve(at)steveklabnik.com

(If your name is missing, PLEASE let us know!)

License

See {LICENSE.txt} for permissions.

Thanks!

-The RubyGems Team

Constant Summary

Class Attribute Summary

Class Method Summary

Class Attribute Details

.configuration (rw)

The standard configuration object for gems.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 343

def self.configuration
  @configuration ||= Gem::ConfigFile.new []
end

.configuration=(config) (rw)

Use the given configuration object (which implements the ::Gem::ConfigFile protocol) as the standard configuration object.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 351

def self.configuration=(config)
  @configuration = config
end

.disable_system_update_message (rw)

RubyGems distributors (like operating system package managers) can disable RubyGems update by setting this to error message printed to end-users on gem update –system instead of actual update.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 1180

attr_accessor :disable_system_update_message

.done_installing_hooks (readonly)

The list of hooks to be run after ::Gem::DependencyInstaller installs a set of gems

[ GitHub ]

  
# File 'lib/rubygems.rb', line 1258

attr_reader :done_installing_hooks

.gemdeps (readonly)

GemDependencyAPI object, which is set when .use_gemdeps is called. This contains all the information from the Gemfile.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 1191

attr_reader :gemdeps

.host (rw)

Get the default RubyGems API host. This is normally https://rubygems.org.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 572

def self.host
  @host ||= Gem::DEFAULT_HOST
end

.host=(host) (rw)

Set the default RubyGems API host.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 578

def self.host=(host)
  @host = host
end

.java_platform?Boolean (readonly)

Is this a java platform?

[ GitHub ]

  
# File 'lib/rubygems.rb', line 1025

def self.java_platform?
  RUBY_PLATFORM == "java"
end

.loaded_specs (readonly)

Hash of loaded ::Gem::Specification keyed by name

[ GitHub ]

  
# File 'lib/rubygems.rb', line 1185

attr_reader :loaded_specs

.paths (rw)

Retrieve the ::Gem::PathSupport object that RubyGems uses to lookup files.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 376

def self.paths
  @paths ||= Gem::PathSupport.new(ENV)
end

.paths=(env) (rw)

Initialize the filesystem paths to use from env. env is a hash-like object (typically ENV) that is queried for ‘GEM_HOME’, ‘GEM_PATH’, and ‘GEM_SPEC_CACHE’ Keys for the env hash should be Strings, and values of the hash should be Strings or nil.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 386

def self.paths=(env)
  clear_paths
  target = {}
  env.each_pair do |k,v|
    case k
    when 'GEM_HOME', 'GEM_PATH', 'GEM_SPEC_CACHE'
      case v
      when nil, String
        target[k] = v
      when Array
        unless Gem::Deprecate.skip
          warn <<-EOWARN
Array values in the parameter to `Gem.paths=` are deprecated.
Please use a String or nil.
An Array (#{env.inspect}) was passed in from #{caller[3]}
          EOWARN
        end
        target[k] = v.join File::PATH_SEPARATOR
      end
    else
      target[k] = v
    end
  end
  @paths = Gem::PathSupport.new ENV.to_hash.merge(target)
  Gem::Specification.dirs = @paths.path
end

.platforms (rw)

Array of platforms this RubyGems supports.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 677

def self.platforms
  @platforms ||= []
  if @platforms.empty?
    @platforms = [Gem::Platform::RUBY, Gem::Platform.local]
  end
  @platforms
end

.platforms=(platforms) (rw)

Set array of platforms this RubyGems supports (primarily for testing).

[ GitHub ]

  
# File 'lib/rubygems.rb', line 670

def self.platforms=(platforms)
  @platforms = platforms
end

.post_build_hooks (readonly)

The list of hooks to be run after Installer#install extracts files and builds extensions

[ GitHub ]

  
# File 'lib/rubygems.rb', line 1246

attr_reader :post_build_hooks

.post_install_hooks (readonly)

The list of hooks to be run after Installer#install completes installation

[ GitHub ]

  
# File 'lib/rubygems.rb', line 1252

attr_reader :post_install_hooks

.post_reset_hooks (readonly)

The list of hooks to be run after Specification.reset is run.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 1263

attr_reader :post_reset_hooks

.post_uninstall_hooks (readonly)

The list of hooks to be run after Uninstaller#uninstall completes installation

[ GitHub ]

  
# File 'lib/rubygems.rb', line 1269

attr_reader :post_uninstall_hooks

.pre_install_hooks (readonly)

The list of hooks to be run before Installer#install does any work

[ GitHub ]

  
# File 'lib/rubygems.rb', line 1274

attr_reader :pre_install_hooks

.pre_reset_hooks (readonly)

The list of hooks to be run before Specification.reset is run.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 1279

attr_reader :pre_reset_hooks

.pre_uninstall_hooks (readonly)

The list of hooks to be run before Uninstaller#uninstall does any work

[ GitHub ]

  
# File 'lib/rubygems.rb', line 1285

attr_reader :pre_uninstall_hooks

.sources (rw)

Returns an Array of sources to fetch remote gems from. Uses default_sources if the sources list is empty.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 911

def self.sources
  source_list = configuration.sources || default_sources
  @sources ||= Gem::SourceList.from(source_list)
end

.sources=(new_sources) (rw)

Need to be able to set the sources without calling .sources.replace since that would cause an infinite loop.

DOC: This comment is not documentation about the method itself, it’s more of a code comment about the implementation.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 923

def self.sources=(new_sources)
  if !new_sources
    @sources = nil
  else
    @sources = Gem::SourceList.from(new_sources)
  end
end

.win_platform?Boolean (readonly)

Is this a windows platform?

[ GitHub ]

  
# File 'lib/rubygems.rb', line 1013

def self.win_platform?
  if @@win_platform.nil?
    ruby_platform = RbConfig::CONFIG['host_os']
    @@win_platform = !!WIN_PATTERNS.find {|r| ruby_platform =~ r }
  end

  @@win_platform
end

Class Method Details

.activate_bin_path(name, exec_name = nil, *requirements)

This method is for internal use only.

Find the full path to the executable for gem name. If the exec_name is not given, an exception will be raised, otherwise the specified executable’s path is returned. requirements allows you to specify specific gem versions.

A side effect of this method is that it will activate the gem that contains the executable.

This method should only be used in bin stub files.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 296

def self.activate_bin_path(name, exec_name = nil, *requirements) # :nodoc:
  spec = find_spec_for_exe name, exec_name, requirements
  Gem::LOADED_SPECS_MUTEX.synchronize do
    spec.activate
    finish_resolve
  end
  spec.bin_file exec_name
end

.activated_gem_paths

The number of paths in the $LOAD_PATH from activated gems. Used to prioritize -I and ‘ENV` entries during require.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 600

def self.activated_gem_paths
  @activated_gem_paths ||= 0
end

.add_to_load_path(*paths)

Add a list of paths to the $LOAD_PATH at the proper place.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 607

def self.add_to_load_path(*paths)
  @activated_gem_paths = activated_gem_paths + paths.size

  # gem directories must come after -I and ENV['RUBYLIB']
  $LOAD_PATH.insert(Gem.load_path_insert_index, *paths)
end

.already_loaded?(file) ⇒ Boolean (private)

[ GitHub ]

  
# File 'lib/rubygems.rb', line 1289

def already_loaded?(file)
  $LOADED_FEATURES.any? do |feature_path|
    feature_path.end_with?(file) && default_gem_load_paths.any? {|load_path_entry| feature_path == "#{load_path_entry}/#{file}" }
  end
end

.bin_path(name, exec_name = nil, *requirements)

Find the full path to the executable for gem name. If the exec_name is not given, an exception will be raised, otherwise the specified executable’s path is returned. requirements allows you to specify specific gem versions.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 251

def self.bin_path(name, exec_name = nil, *requirements)
  requirements = Gem::Requirement.default if
    requirements.empty?

  find_spec_for_exe(name, exec_name, requirements).bin_file exec_name
end

.binary_mode

The mode needed to read a file as straight binary.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 308

def self.binary_mode
  'rb'
end

.bindir(install_dir = Gem.dir)

The path where gem executables are to be installed.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 315

def self.bindir(install_dir=Gem.dir)
  return File.join install_dir, 'bin' unless
    install_dir.to_s == Gem.default_dir.to_s
  Gem.default_bindir
end

.cache_home

The path to standard location of the user’s cache directory.

[ GitHub ]

  
# File 'lib/rubygems/defaults.rb', line 153

def self.cache_home
  @cache_home ||= (ENV["XDG_CACHE_HOME"] || File.join(Gem.user_home, '.cache'))
end

.clear_default_specs

Clear default gem related variables. It is for test

[ GitHub ]

  
# File 'lib/rubygems.rb', line 1238

def clear_default_specs
  @path_to_default_spec_map.clear
end

.clear_paths

Reset the .dir and .path values. The next time .dir or .path is requested, the values will be calculated from scratch. This is mainly used by the unit tests to provide test isolation.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 333

def self.clear_paths
  @paths         = nil
  @user_home     = nil
  Gem::Specification.reset
  Gem::Security.reset if defined?(Gem::Security)
end

.config_file

The path to standard location of the user’s .gemrc file.

[ GitHub ]

  
# File 'lib/rubygems/defaults.rb', line 146

def self.config_file
  @config_file ||= find_config_file.tap(&Gem::UNTAINT)
end

.config_home

The path to standard location of the user’s configuration directory.

[ GitHub ]

  
# File 'lib/rubygems/defaults.rb', line 127

def self.config_home
  @config_home ||= (ENV["XDG_CONFIG_HOME"] || File.join(Gem.user_home, '.config'))
end

.data_home

The path to standard location of the user’s data directory.

[ GitHub ]

  
# File 'lib/rubygems/defaults.rb', line 160

def self.data_home
  @data_home ||= (ENV["XDG_DATA_HOME"] || File.join(Gem.user_home, '.local', 'share'))
end

.datadir(gem_name)

The path to the data directory specified by the gem name. If the package is not available as a gem, return nil.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 359

def self.datadir(gem_name)
  spec = @loaded_specs[gem_name]
  return nil if spec.nil?
  spec.datadir
end

.default_bindir

The default directory for binaries

[ GitHub ]

  
# File 'lib/rubygems/defaults.rb', line 199

def self.default_bindir
  if defined? RUBY_FRAMEWORK_VERSION # mac framework support
    '/usr/local/bin'
  else # generic install
    RbConfig::CONFIG['bindir']
  end
end

.default_cert_path

The default signing certificate chain path

[ GitHub ]

  
# File 'lib/rubygems/defaults.rb', line 227

def self.default_cert_path
  default_cert_path = File.join Gem.user_home, ".gem", "gem-public_cert.pem"

  unless File.exist?(default_cert_path)
    default_cert_path = File.join Gem.data_home, "gem", "gem-public_cert.pem"
  end

  default_cert_path
end

.default_dir

Default home directory path to be used if an alternate value is not specified in the environment

[ GitHub ]

  
# File 'lib/rubygems/defaults.rb', line 36

def self.default_dir
  path = if defined? RUBY_FRAMEWORK_VERSION
           [
             File.dirname(RbConfig::CONFIG['sitedir']),
             'Gems',
             RbConfig::CONFIG['ruby_version'],
           ]
         else
           [
             RbConfig::CONFIG['rubylibprefix'],
             'gems',
             RbConfig::CONFIG['ruby_version'],
           ]
         end

  @default_dir ||= File.join(*path)
end

.default_exec_format

Deduce Ruby’s –program-prefix and –program-suffix from its install name

[ GitHub ]

  
# File 'lib/rubygems/defaults.rb', line 185

def self.default_exec_format
  exec_format = RbConfig::CONFIG['ruby_install_name'].sub('ruby', '%s') rescue '%s'

  unless exec_format =~ /%s/
    raise Gem::Exception,
      "[BUG] invalid exec_format #{exec_format.inspect}, no %s"
  end

  exec_format
end

.default_ext_dir_for(base_dir)

Returns binary extensions dir for specified RubyGems base dir or nil if such directory cannot be determined.

By default, the binary extensions are located side by side with their Ruby counterparts, therefore nil is returned

[ GitHub ]

  
# File 'lib/rubygems/defaults.rb', line 61

def self.default_ext_dir_for(base_dir)
  nil
end

.default_gem_load_paths (private)

[ GitHub ]

  
# File 'lib/rubygems.rb', line 1295

def default_gem_load_paths
  @default_gem_load_paths ||= $LOAD_PATH[load_path_insert_index..-1]
end

.default_key_path

The default signing key path

[ GitHub ]

  
# File 'lib/rubygems/defaults.rb', line 214

def self.default_key_path
  default_key_path = File.join Gem.user_home, ".gem", "gem-private_key.pem"

  unless File.exist?(default_key_path)
    default_key_path = File.join Gem.data_home, "gem", "gem-private_key.pem"
  end

  default_key_path
end

.default_path

Default gem load path

[ GitHub ]

  
# File 'lib/rubygems/defaults.rb', line 174

def self.default_path
  path = []
  path << user_dir if user_home && File.exist?(user_home)
  path << default_dir
  path << vendor_dir if vendor_dir and File.directory? vendor_dir
  path
end

.default_rubygems_dirs

Paths where RubyGems’ .rb files and bin files are installed

[ GitHub ]

  
# File 'lib/rubygems/defaults.rb', line 68

def self.default_rubygems_dirs
  nil # default to standard layout
end

.default_sources

An Array of the default sources that come with RubyGems

[ GitHub ]

  
# File 'lib/rubygems/defaults.rb', line 14

def self.default_sources
  %w[https://rubygems.org/]
end

.default_spec_cache_dir

Default spec directory path to be used if an alternate value is not specified in the environment

[ GitHub ]

  
# File 'lib/rubygems/defaults.rb', line 22

def self.default_spec_cache_dir
  default_spec_cache_dir = File.join Gem.user_home, '.gem', 'specs'

  unless File.exist?(default_spec_cache_dir)
    default_spec_cache_dir = File.join Gem.data_home, 'gem', 'specs'
  end

  default_spec_cache_dir
end

.default_specifications_dir

Path to specification files of default gems.

[ GitHub ]

  
# File 'lib/rubygems/defaults.rb', line 75

def self.default_specifications_dir
  @default_specifications_dir ||= File.join(Gem.default_dir, "specifications", "default")
end

.deflate(data)

A Zlib::Deflate.deflate wrapper

[ GitHub ]

  
# File 'lib/rubygems.rb', line 368

def self.deflate(data)
  require 'zlib'
  Zlib::Deflate.deflate data
end

.dir

The path where gems are to be installed.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 416

def self.dir
  paths.home
end

.done_installing(&hook)

Adds a post-installs hook that will be passed a ::Gem::DependencyInstaller and a list of installed specifications when DependencyInstaller#install is complete

[ GitHub ]

  
# File 'lib/rubygems.rb', line 709

def self.done_installing(&hook)
  @done_installing_hooks << hook
end

.ensure_default_gem_subdirectories(dir = Gem.dir, mode = nil)

Quietly ensure the Gem directory .dir contains all the proper subdirectories for handling default gems. If we can’t create a directory due to a permission problem, then we will silently continue.

If mode is given, missing directories are created with this mode.

World-writable directories will never be created.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 450

def self.ensure_default_gem_subdirectories(dir = Gem.dir, mode = nil)
  ensure_subdirectories(dir, mode, REPOSITORY_DEFAULT_GEM_SUBDIRECTORIES)
end

.ensure_gem_subdirectories(dir = Gem.dir, mode = nil)

Quietly ensure the Gem directory .dir contains all the proper subdirectories. If we can’t create a directory due to a permission problem, then we will silently continue.

If mode is given, missing directories are created with this mode.

World-writable directories will never be created.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 437

def self.ensure_gem_subdirectories(dir = Gem.dir, mode = nil)
  ensure_subdirectories(dir, mode, REPOSITORY_SUBDIRECTORIES)
end

.ensure_subdirectories(dir, mode, subdirs)

This method is for internal use only.
[ GitHub ]

  
# File 'lib/rubygems.rb', line 454

def self.ensure_subdirectories(dir, mode, subdirs) # :nodoc:
  old_umask = File.umask
  File.umask old_umask | 002

  require 'fileutils'

  options = {}

  options[:mode] = mode if mode

  subdirs.each do |name|
    subdir = File.join dir, name
    next if File.exist? subdir
    begin
      FileUtils.mkdir_p subdir, **options
    rescue SystemCallError
    end
  end
ensure
  File.umask old_umask
end

.env_requirement(gem_name)

[ GitHub ]

  
# File 'lib/rubygems.rb', line 840

def self.env_requirement(gem_name)
  @env_requirements_by_name ||= {}
  @env_requirements_by_name[gem_name] ||= begin
    req = ENV["GEM_REQUIREMENT_#{gem_name.upcase}"] || '>= 0'.freeze
    Gem::Requirement.create(req)
  end
end

.extension_api_version

This method is for internal use only.

The extension API version of ruby. This includes the static vs non-static distinction as extensions cannot be shared between the two.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 480

def self.extension_api_version # :nodoc:
  if 'no' == RbConfig::CONFIG['ENABLE_SHARED']
    "#{ruby_api_version}-static"
  else
    ruby_api_version
  end
end

.find_config_file

Finds the user’s config file

[ GitHub ]

  
# File 'lib/rubygems/defaults.rb', line 134

def self.find_config_file
  gemrc = File.join Gem.user_home, '.gemrc'
  if File.exist? gemrc
    gemrc
  else
    File.join Gem.config_home, "gem", "gemrc"
  end
end

.find_files(glob, check_load_path = true)

Returns a list of paths matching glob that can be used by a gem to pick up features from other gems. For example:

Gem.find_files('rdoc/discover').each do |path| load path end

if check_load_path is true (the default), then find_files also searches $LOAD_PATH for files as well as gems.

Note that find_files will return all files even if they are from different versions of the same gem. See also find_latest_files

[ GitHub ]

  
# File 'lib/rubygems.rb', line 500

def self.find_files(glob, check_load_path=true)
  files = []

  files = find_files_from_load_path glob if check_load_path

  gem_specifications = @gemdeps ? Gem.loaded_specs.values : Gem::Specification.stubs

  files.concat gem_specifications.map {|spec|
    spec.matches_for_glob("#{glob}#{Gem.suffix_pattern}")
  }.flatten

  # $LOAD_PATH might contain duplicate entries or reference
  # the spec dirs directly, so we prune.
  files.uniq! if check_load_path

  return files
end

.find_files_from_load_path(glob)

This method is for internal use only.
[ GitHub ]

  
# File 'lib/rubygems.rb', line 518

def self.find_files_from_load_path(glob) # :nodoc:
  glob_with_suffixes = "#{glob}#{Gem.suffix_pattern}"
  $LOAD_PATH.map do |load_path|
    Gem::Util.glob_files_in_dir(glob_with_suffixes, load_path)
  end.flatten.select {|file| File.file? file.tap(&Gem::UNTAINT) }
end

.find_home (private)

Finds the user’s home directory.

[ GitHub ]

  
# File 'lib/rubygems/defaults.rb', line 94

def self.find_home
  Dir.home.dup
rescue
  if Gem.win_platform?
    File.expand_path File.join(ENV['HOMEDRIVE'] || ENV['SystemDrive'], '/')
  else
    File.expand_path "/"
  end
end

.find_latest_files(glob, check_load_path = true)

Returns a list of paths matching glob from the latest gems that can be used by a gem to pick up features from other gems. For example:

Gem.find_latest_files('rdoc/discover').each do |path| load path end

if check_load_path is true (the default), then find_latest_files also searches $LOAD_PATH for files as well as gems.

Unlike find_files, find_latest_files will return only files from the latest version of a gem.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 537

def self.find_latest_files(glob, check_load_path=true)
  files = []

  files = find_files_from_load_path glob if check_load_path

  files.concat Gem::Specification.latest_specs(true).map {|spec|
    spec.matches_for_glob("#{glob}#{Gem.suffix_pattern}")
  }.flatten

  # $LOAD_PATH might contain duplicate entries or reference
  # the spec dirs directly, so we prune.
  files.uniq! if check_load_path

  return files
end

.find_spec_for_exe(name, exec_name, requirements) (private)

Raises:

  • (ArgumentError)
[ GitHub ]

  
# File 'lib/rubygems.rb', line 258

def self.find_spec_for_exe(name, exec_name, requirements)
  raise ArgumentError, "you must supply exec_name" unless exec_name

  dep = Gem::Dependency.new name, requirements

  loaded = Gem.loaded_specs[name]

  return loaded if loaded && dep.matches_spec?(loaded)

  specs = dep.matching_specs(true)

  specs = specs.find_all do |spec|
    spec.executables.include? exec_name
  end if exec_name

  unless spec = specs.first
    msg = "can't find gem #{dep} with executable #{exec_name}"
    if dep.filters_bundler? && bundler_message = Gem::BundlerVersionFinder.missing_version_message
      msg = bundler_message
    end
    raise Gem::GemNotFoundException, msg
  end

  spec
end

.find_unresolved_default_spec(path)

Find a ::Gem::Specification of default gem from .path

[ GitHub ]

  
# File 'lib/rubygems.rb', line 1230

def find_unresolved_default_spec(path)
  default_spec = @path_to_default_spec_map[path]
  return default_spec if default_spec && loaded_specs[default_spec.name] != default_spec
end

.finish_resolve(request_set = Gem::RequestSet.new)

[ GitHub ]

  
# File 'lib/rubygems.rb', line 236

def self.finish_resolve(request_set=Gem::RequestSet.new)
  request_set.import Gem::Specification.unresolved_deps.values
  request_set.import Gem.loaded_specs.values.map {|s| Gem::Dependency.new(s.name, s.version) }

  request_set.resolve_current.each do |s|
    s.full_spec.activate
  end
end

.install(name, version = Gem::Requirement.default, *options)

Top level install helper method. Allows you to install gems interactively:

% irb
>> Gem.install "minitest"
Fetching: minitest-5.14.gem (100%)
#=> [#<Gem::Specification:0x1013b4528 @name="minitest", ...>]
[ GitHub ]

  
# File 'lib/rubygems.rb', line 561

def self.install(name, version = Gem::Requirement.default, *options)
  require_relative "rubygems/dependency_installer"
  inst = Gem::DependencyInstaller.new(*options)
  inst.install name, version
  inst.installed_gems
end

.install_extension_in_lib

This method is for internal use only.

Install extensions into lib as well as into the extension directory.

[ GitHub ]

  
# File 'lib/rubygems/defaults.rb', line 240

def self.install_extension_in_lib # :nodoc:
  true
end

.latest_rubygems_version

Returns the latest release version of RubyGems.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 865

def self.latest_rubygems_version
  latest_version_for('rubygems-update') or
    raise "Can't find 'rubygems-update' in any repo. Check `gem source list`."
end

.latest_spec_for(name)

Returns the latest release-version specification for the gem name.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 852

def self.latest_spec_for(name)
  dependency   = Gem::Dependency.new name
  fetcher      = Gem::SpecFetcher.fetcher
  spec_tuples, = fetcher.spec_for_dependency dependency

  spec, = spec_tuples.first

  spec
end

.latest_version_for(name)

Returns the version of the latest release-version of gem name

[ GitHub ]

  
# File 'lib/rubygems.rb', line 873

def self.latest_version_for(name)
  spec = latest_spec_for name
  spec and spec.version
end

.load_env_plugins

Find all ‘rubygems_plugin’ files in $LOAD_PATH and load them

[ GitHub ]

  
# File 'lib/rubygems.rb', line 1061

def self.load_env_plugins
  load_plugin_files find_files_from_load_path("rubygems_plugin")
end

.load_path_insert_index

The index to insert activated gem paths into the $LOAD_PATH. The activated gem’s paths are inserted before site lib directory by default.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 586

def self.load_path_insert_index
  $LOAD_PATH.each_with_index do |path, i|
    return i if path.instance_variable_defined?(:@gem_prelude_index)
  end

  index = $LOAD_PATH.index RbConfig::CONFIG['sitelibdir']

  index || 0
end

.load_plugin_files(plugins)

This method is for internal use only.

Load plugins as Ruby files

[ GitHub ]

  
# File 'lib/rubygems.rb', line 1032

def self.load_plugin_files(plugins) # :nodoc:
  plugins.each do |plugin|

    # Skip older versions of the GemCutter plugin: Its commands are in
    # RubyGems proper now.

    next if plugin =~ /gemcutter-0\.[0-3]/

    begin
      load plugin
    rescue ::Exception => e
      details = "#{plugin.inspect}: #{e.message} (#{e.class})"
      warn "Error loading RubyGems plugin #{details}"
    end
  end
end

.load_plugins

Find rubygems plugin files in the standard location and load them

[ GitHub ]

  
# File 'lib/rubygems.rb', line 1052

def self.load_plugins
  Gem.path.each do |gem_path|
    load_plugin_files Gem::Util.glob_files_in_dir("*#{Gem.plugin_suffix_pattern}", plugindir(gem_path))
  end
end

.load_yaml

Loads YAML, preferring ::Psych

[ GitHub ]

  
# File 'lib/rubygems.rb', line 619

def self.load_yaml
  return if @yaml_loaded

  begin
    # Try requiring the gem version *or* stdlib version of psych.
    require 'psych'
  rescue ::LoadError
    # If we can't load psych, that's fine, go on.
  else
    require_relative 'rubygems/psych_additions'
    require_relative 'rubygems/psych_tree'
  end

  require 'yaml'
  require_relative 'rubygems/safe_yaml'

  @yaml_loaded = true
end

.location_of_caller(depth = 1)

The file name and line number of the caller of the caller of this method.

depth is how many layers up the call stack it should go.

e.g.,

def a; Gem.location_of_caller; end a #=> [“x.rb”, 2] # (it’ll vary depending on file name and line number)

def b; c; end def c; location_of_caller(2); end b #=> [“x.rb”, 6] # (it’ll vary depending on file name and line number)

[ GitHub ]

  
# File 'lib/rubygems.rb', line 652

def self.location_of_caller(depth = 1)
  caller[depth] =~ /(.*?):(\d+).*?$/i
  file = $1
  lineno = $2.to_i

  [file, lineno]
end

.marshal_version

The version of the Marshal format for your Ruby.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 663

def self.marshal_version
  "#{Marshal::MAJOR_VERSION}.#{Marshal::MINOR_VERSION}"
end

.needs {|rs| ... }

Yields:

  • (rs)
[ GitHub ]

  
# File 'lib/rubygems.rb', line 228

def self.needs
  rs = Gem::RequestSet.new

  yield rs

  finish_resolve rs
end

.operating_system_defaults

Default options for gem commands for Ruby packagers.

The options here should be structured as an array of string “gem” command names as keys and a string of the default options as values.

Example:

def self.operating_system_defaults

{
    'install' => '--no-rdoc --no-ri --env-shebang',
    'update' => '--no-rdoc --no-ri --env-shebang'
}

end

[ GitHub ]

  
# File 'lib/rubygems/defaults.rb', line 273

def self.operating_system_defaults
  {}
end

.path

[ GitHub ]

  
# File 'lib/rubygems.rb', line 420

def self.path
  paths.path
end

.path_separator

How String Gem paths should be split. Overridable for esoteric platforms.

[ GitHub ]

  
# File 'lib/rubygems/defaults.rb', line 167

def self.path_separator
  File::PATH_SEPARATOR
end

.platform_defaults

Default options for gem commands for Ruby implementers.

The options here should be structured as an array of string “gem” command names as keys and a string of the default options as values.

Example:

def self.platform_defaults

{
    'install' => '--no-rdoc --no-ri --env-shebang',
    'update' => '--no-rdoc --no-ri --env-shebang'
}

end

[ GitHub ]

  
# File 'lib/rubygems/defaults.rb', line 292

def self.platform_defaults
  {}
end

.plugin_suffix_pattern

Glob pattern for require-able plugin suffixes.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 948

def self.plugin_suffix_pattern
  @plugin_suffix_pattern ||= "_plugin#{suffix_pattern}"
end

.plugin_suffix_regexp

Regexp for require-able plugin suffixes.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 955

def self.plugin_suffix_regexp
  @plugin_suffix_regexp ||= /_plugin#{suffix_regexp}\z/
end

.plugindir(install_dir = Gem.dir)

The path were rubygems plugins are to be installed.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 324

def self.plugindir(install_dir=Gem.dir)
  File.join install_dir, 'plugins'
end

.post_build(&hook)

Adds a post-build hook that will be passed an ::Gem::Installer instance when Installer#install is called. The hook is called after the gem has been extracted and extensions have been built but before the executables or gemspec has been written. If the hook returns false then the gem’s files will be removed and the install will be aborted.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 692

def self.post_build(&hook)
  @post_build_hooks << hook
end

.post_install(&hook)

Adds a post-install hook that will be passed an ::Gem::Installer instance when Installer#install is called

[ GitHub ]

  
# File 'lib/rubygems.rb', line 700

def self.post_install(&hook)
  @post_install_hooks << hook
end

.post_reset(&hook)

Adds a hook that will get run after Specification.reset is run.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 717

def self.post_reset(&hook)
  @post_reset_hooks << hook
end

.post_uninstall(&hook)

Adds a post-uninstall hook that will be passed a ::Gem::Uninstaller instance and the spec that was uninstalled when Uninstaller#uninstall is called

[ GitHub ]

  
# File 'lib/rubygems.rb', line 726

def self.post_uninstall(&hook)
  @post_uninstall_hooks << hook
end

.pre_install(&hook)

Adds a pre-install hook that will be passed an ::Gem::Installer instance when Installer#install is called. If the hook returns false then the install will be aborted.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 735

def self.pre_install(&hook)
  @pre_install_hooks << hook
end

.pre_reset(&hook)

Adds a hook that will get run before Specification.reset is run.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 743

def self.pre_reset(&hook)
  @pre_reset_hooks << hook
end

.pre_uninstall(&hook)

Adds a pre-uninstall hook that will be passed an ::Gem::Uninstaller instance and the spec that will be uninstalled when Uninstaller#uninstall is called

[ GitHub ]

  
# File 'lib/rubygems.rb', line 752

def self.pre_uninstall(&hook)
  @pre_uninstall_hooks << hook
end

.prefix

The directory prefix this RubyGems was installed at. If your prefix is in a standard location (ie, rubygems is installed where you’d expect it to be), then prefix returns nil.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 761

def self.prefix
  prefix = File.dirname RUBYGEMS_DIR

  if prefix != File.expand_path(RbConfig::CONFIG['sitelibdir']) and
     prefix != File.expand_path(RbConfig::CONFIG['libdir']) and
     'lib' == File.basename(RUBYGEMS_DIR)
    prefix
  end
end

.read_binary(path)

Safely read a file in binary mode on all platforms.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 781

def self.read_binary(path)
  File.open path, 'rb+' do |f|
    f.flock(File::LOCK_EX)
    f.read
  end
rescue *READ_BINARY_ERRORS
  File.open path, 'rb' do |f|
    f.read
  end
rescue Errno::ENOLCK # NFS
  if Thread.main != Thread.current
    raise
  else
    File.open path, 'rb' do |f|
      f.read
    end
  end
end

.refresh

Refresh available gems from disk.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 774

def self.refresh
  Gem::Specification.reset
end

.register_default_spec(spec)

Register a ::Gem::Specification for default gem.

Two formats for the specification are supported:

  • MRI 2.0 style, where spec.files contains unprefixed require names. The spec’s filenames will be registered as-is.

  • New style, where spec.files contains files prefixed with paths from spec.require_paths. The prefixes are stripped before registering the spec’s filenames. Unprefixed files are omitted.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 1205

def register_default_spec(spec)
  extended_require_paths = spec.require_paths.map {|f| f + "/" }
  new_format = extended_require_paths.any? {|path| spec.files.any? {|f| f.start_with? path } }

  if new_format
    prefix_group = extended_require_paths.join("|")
    prefix_pattern = /^(#{prefix_group})/
  end

  spec.files.each do |file|
    if new_format
      file = file.sub(prefix_pattern, "")
      next unless $~
    end

    spec.activate if already_loaded?(file)

    @path_to_default_spec_map[file] = spec
    @path_to_default_spec_map[file.sub(suffix_regexp, "")] = spec
  end
end

.ruby

The path to the running Ruby interpreter.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 823

def self.ruby
  if @ruby.nil?
    @ruby = RbConfig.ruby

    @ruby = "\"#{@ruby}\"" if @ruby =~ /\s/
  end

  @ruby
end

.ruby_api_version

Returns a String containing the API compatibility version of Ruby

[ GitHub ]

  
# File 'lib/rubygems.rb', line 836

def self.ruby_api_version
  @ruby_api_version ||= RbConfig::CONFIG['ruby_version'].dup
end

.ruby_engine

[ GitHub ]

  
# File 'lib/rubygems/defaults.rb', line 207

def self.ruby_engine
  RUBY_ENGINE
end

.ruby_version

A ::Gem::Version for the currently running Ruby.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 881

def self.ruby_version
  return @ruby_version if defined? @ruby_version
  version = RUBY_VERSION.dup

  if defined?(RUBY_PATCHLEVEL) && RUBY_PATCHLEVEL != -1
    version << ".#{RUBY_PATCHLEVEL}"
  elsif defined?(RUBY_DESCRIPTION)
    if RUBY_ENGINE == "ruby"
      desc = RUBY_DESCRIPTION[/\Aruby #{Regexp.quote(RUBY_VERSION)}([^ ]+) /, 1]
    else
      desc = RUBY_DESCRIPTION[/\A#{RUBY_ENGINE} #{Regexp.quote(RUBY_ENGINE_VERSION)} \(#{RUBY_VERSION}([^ ]+)\) /, 1]
    end
    version << ".#{desc}" if desc
  end

  @ruby_version = Gem::Version.new version
end

.rubygems_version

A ::Gem::Version for the currently running RubyGems

[ GitHub ]

  
# File 'lib/rubygems.rb', line 902

def self.rubygems_version
  return @rubygems_version if defined? @rubygems_version
  @rubygems_version = Gem::Version.new Gem::VERSION
end

.source_date_epoch

Returns the value of .source_date_epoch_string, as a Time object.

This is used throughout RubyGems for enabling reproducible builds.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 1168

def self.source_date_epoch
  Time.at(self.source_date_epoch_string.to_i).utc.freeze
end

.source_date_epoch_string

If the SOURCE_DATE_EPOCH environment variable is set, returns it’s value. Otherwise, returns the time that source_date_epoch_string was first called in the same format as SOURCE_DATE_EPOCH.

NOTE(@duckinator): The implementation is a tad weird because we want to:

1. Make builds reproducible by default, by having this function always
   return the same result during a given run.
2. Allow changing ENV['SOURCE_DATE_EPOCH'] at runtime, since multiple
   tests that set this variable will be run in a single process.

If you simplify this function and a lot of tests fail, that is likely due to #2 above.

Details on SOURCE_DATE_EPOCH: reproducible-builds.org/specs/source-date-epoch/

[ GitHub ]

  
# File 'lib/rubygems.rb', line 1149

def self.source_date_epoch_string
  # The value used if $SOURCE_DATE_EPOCH is not set.
  @default_source_date_epoch ||= Time.now.to_i.to_s

  specified_epoch = ENV["SOURCE_DATE_EPOCH"]

  # If it's empty or just whitespace, treat it like it wasn't set at all.
  specified_epoch = nil if !specified_epoch.nil? && specified_epoch.strip.empty?

  epoch = specified_epoch || @default_source_date_epoch

  epoch.strip
end

.spec_cache_dir

[ GitHub ]

  
# File 'lib/rubygems.rb', line 424

def self.spec_cache_dir
  paths.spec_cache_dir
end

.suffix_pattern

Glob pattern for require-able path suffixes.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 934

def self.suffix_pattern
  @suffix_pattern ||= "{#{suffixes.join(',')}}"
end

.suffix_regexp

Regexp for require-able path suffixes.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 941

def self.suffix_regexp
  @suffix_regexp ||= /#{Regexp.union(suffixes)}\z/
end

.suffixes

Suffixes for require-able paths.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 962

def self.suffixes
  @suffixes ||= ['',
                 '.rb',
                 *%w[DLEXT DLEXT2].map do |key|
                   val = RbConfig::CONFIG[key]
                   next unless val and not val.empty?
                   ".#{val}"
                 end,
                ].compact.uniq
end

.time(msg, width = 0, display = Gem.configuration.verbose)

Prints the amount of time the supplied block takes to run using the debug UI output.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 977

def self.time(msg, width = 0, display = Gem.configuration.verbose)
  now = Time.now

  value = yield

  elapsed = Time.now - now

  ui.say "%2$*1$s: %3$3.3fs" % [-width, msg, elapsed] if display

  value
end

.try_activate(path)

Try to activate a gem containing .path. Returns true if activation succeeded or wasn’t needed because it was already activated. Returns false if it can’t find the path in a gem.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 203

def self.try_activate(path)
  # finds the _latest_ version... regardless of loaded specs and their deps
  # if another gem had a requirement that would mean we shouldn't
  # activate the latest version, then either it would already be activated
  # or if it was ambiguous (and thus unresolved) the code in our custom
  # require will try to activate the more specific version.

  spec = Gem::Specification.find_by_path path
  return false unless spec
  return true if spec.activated?

  begin
    spec.activate
  rescue Gem::LoadError => e # this could fail due to gem dep collisions, go lax
    spec_by_name = Gem::Specification.find_by_name(spec.name)
    if spec_by_name.nil?
      raise e
    else
      spec_by_name.activate
    end
  end

  return true
end

.ui

Lazily loads ::Gem::DefaultUserInteraction and returns the default UI.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 992

def self.ui
  require_relative 'rubygems/user_interaction'

  Gem::DefaultUserInteraction.ui
end

.use_gemdeps(path = nil)

Looks for a gem dependency file at .path and activates the gems in the file if found. If the file is not found an ArgumentError is raised.

If .path is not given the RUBYGEMS_GEMDEPS environment variable is used, but if no file is found no exception is raised.

If ‘-’ is given for .path RubyGems searches up from the current working directory for gem dependency files (gem.deps.rb, Gemfile, Isolate) and activates the gems in the first one found.

You can run this automatically when rubygems starts. To enable, set the RUBYGEMS_GEMDEPS environment variable to either the path of your gem dependencies file or “-” to auto-discover in parent directories.

NOTE: Enabling automatic discovery on multiuser systems can lead to execution of arbitrary code when used from directories outside your control.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 1085

def self.use_gemdeps(path = nil)
  raise_exception = path

  path ||= ENV['RUBYGEMS_GEMDEPS']
  return unless path

  path = path.dup

  if path == "-"
    Gem::Util.traverse_parents Dir.pwd do |directory|
      dep_file = GEM_DEP_FILES.find {|f| File.file?(f) }

      next unless dep_file

      path = File.join directory, dep_file
      break
    end
  end

  path.tap(&Gem::UNTAINT)

  unless File.file? path
    return unless raise_exception

    raise ArgumentError, "Unable to find gem dependencies file at #{path}"
  end

  ENV["BUNDLE_GEMFILE"] ||= File.expand_path(path)
  require_relative 'rubygems/user_interaction'
  require "bundler"
  begin
    Gem::DefaultUserInteraction.use_ui(ui) do
      begin
        Bundler.ui.silence do
          @gemdeps = Bundler.setup
        end
      ensure
        Gem::DefaultUserInteraction.ui.close
      end
    end
  rescue Bundler::BundlerError => e
    warn e.message
    warn "You may need to `bundle install` to install missing gems"
    warn ""
  end
end

.use_paths(home, *paths)

Use the home and .paths values for .dir and .path. Used mainly by the unit tests to provide environment isolation.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 1002

def self.use_paths(home, *paths)
  paths.flatten!
  paths.compact!
  hash = { "GEM_HOME" => home, "GEM_PATH" => paths.empty? ? home : paths.join(File::PATH_SEPARATOR) }
  hash.delete_if {|_, v| v.nil? }
  self.paths = hash
end

.user_dir

Path for gems in the user’s home directory

[ GitHub ]

  
# File 'lib/rubygems/defaults.rb', line 116

def self.user_dir
  gem_dir = File.join(Gem.user_home, ".gem")
  gem_dir = File.join(Gem.data_home, "gem") unless File.exist?(gem_dir)
  parts = [gem_dir, ruby_engine]
  parts << RbConfig::CONFIG['ruby_version'] unless RbConfig::CONFIG['ruby_version'].empty?
  File.join parts
end

.user_home

The home directory for the user.

[ GitHub ]

  
# File 'lib/rubygems/defaults.rb', line 109

def self.user_home
  @user_home ||= find_home.tap(&Gem::UNTAINT)
end

.vendor_dir

This method is for internal use only.

Directory where vendor gems are installed.

[ GitHub ]

  
# File 'lib/rubygems/defaults.rb', line 247

def self.vendor_dir # :nodoc:
  if vendor_dir = ENV['GEM_VENDOR']
    return vendor_dir.dup
  end

  return nil unless RbConfig::CONFIG.key? 'vendordir'

  File.join RbConfig::CONFIG['vendordir'], 'gems',
            RbConfig::CONFIG['ruby_version']
end

.write_binary(path, data)

Safely write a file in binary mode on all platforms.

[ GitHub ]

  
# File 'lib/rubygems.rb', line 802

def self.write_binary(path, data)
  File.open(path, File::RDWR | File::CREAT | File::BINARY | File::LOCK_EX) do |io|
    io.write data
  end
rescue *WRITE_BINARY_ERRORS
  File.open(path, 'wb') do |io|
    io.write data
  end
rescue Errno::ENOLCK # NFS
  if Thread.main != Thread.current
    raise
  else
    File.open(path, 'wb') do |io|
      io.write data
    end
  end
end