In Files
- rubygems.rb
 - rubygems/available_set.rb
 - rubygems/basic_specification.rb
 - rubygems/command.rb
 - rubygems/command_manager.rb
 - rubygems/commands/build_command.rb
 - rubygems/commands/cert_command.rb
 - rubygems/commands/check_command.rb
 - rubygems/commands/cleanup_command.rb
 - rubygems/commands/contents_command.rb
 - rubygems/commands/dependency_command.rb
 - rubygems/commands/environment_command.rb
 - rubygems/commands/fetch_command.rb
 - rubygems/commands/generate_index_command.rb
 - rubygems/commands/help_command.rb
 - rubygems/commands/install_command.rb
 - rubygems/commands/list_command.rb
 - rubygems/commands/lock_command.rb
 - rubygems/commands/mirror_command.rb
 - rubygems/commands/open_command.rb
 - rubygems/commands/outdated_command.rb
 - rubygems/commands/owner_command.rb
 - rubygems/commands/pristine_command.rb
 - rubygems/commands/push_command.rb
 - rubygems/commands/query_command.rb
 - rubygems/commands/rdoc_command.rb
 - rubygems/commands/search_command.rb
 - rubygems/commands/server_command.rb
 - rubygems/commands/setup_command.rb
 - rubygems/commands/sources_command.rb
 - rubygems/commands/specification_command.rb
 - rubygems/commands/stale_command.rb
 - rubygems/commands/uninstall_command.rb
 - rubygems/commands/unpack_command.rb
 - rubygems/commands/update_command.rb
 - rubygems/commands/which_command.rb
 - rubygems/commands/yank_command.rb
 - rubygems/compatibility.rb
 - rubygems/config_file.rb
 - rubygems/core_ext/kernel_gem.rb
 - rubygems/core_ext/kernel_require.rb
 - rubygems/defaults.rb
 - rubygems/dependency.rb
 - rubygems/dependency_installer.rb
 - rubygems/dependency_list.rb
 - rubygems/deprecate.rb
 - rubygems/doctor.rb
 - rubygems/errors.rb
 - rubygems/exceptions.rb
 - rubygems/ext.rb
 - rubygems/ext/build_error.rb
 - rubygems/ext/builder.rb
 - rubygems/ext/cmake_builder.rb
 - rubygems/ext/configure_builder.rb
 - rubygems/ext/ext_conf_builder.rb
 - rubygems/ext/rake_builder.rb
 - rubygems/gem_runner.rb
 - rubygems/gemcutter_utilities.rb
 - rubygems/indexer.rb
 - rubygems/install_default_message.rb
 - rubygems/install_message.rb
 - rubygems/install_update_options.rb
 - rubygems/installer.rb
 - rubygems/installer_test_case.rb
 - rubygems/local_remote_options.rb
 - rubygems/mock_gem_ui.rb
 - rubygems/name_tuple.rb
 - rubygems/package.rb
 - rubygems/package/digest_io.rb
 - rubygems/package/file_source.rb
 - rubygems/package/io_source.rb
 - rubygems/package/old.rb
 - rubygems/package/source.rb
 - rubygems/package/tar_header.rb
 - rubygems/package/tar_reader.rb
 - rubygems/package/tar_reader/entry.rb
 - rubygems/package/tar_test_case.rb
 - rubygems/package/tar_writer.rb
 - rubygems/package_task.rb
 - rubygems/path_support.rb
 - rubygems/platform.rb
 - rubygems/psych_tree.rb
 - rubygems/rdoc.rb
 - rubygems/remote_fetcher.rb
 - rubygems/request.rb
 - rubygems/request/connection_pools.rb
 - rubygems/request/http_pool.rb
 - rubygems/request/https_pool.rb
 - rubygems/request_set.rb
 - rubygems/request_set/gem_dependency_api.rb
 - rubygems/request_set/lockfile.rb
 - rubygems/request_set/lockfile/parser.rb
 - rubygems/request_set/lockfile/tokenizer.rb
 - rubygems/requirement.rb
 - rubygems/resolver.rb
 - rubygems/resolver/activation_request.rb
 - rubygems/resolver/api_set.rb
 - rubygems/resolver/api_specification.rb
 - rubygems/resolver/best_set.rb
 - rubygems/resolver/composed_set.rb
 - rubygems/resolver/conflict.rb
 - rubygems/resolver/current_set.rb
 - rubygems/resolver/dependency_request.rb
 - rubygems/resolver/git_set.rb
 - rubygems/resolver/git_specification.rb
 - rubygems/resolver/index_set.rb
 - rubygems/resolver/index_specification.rb
 - rubygems/resolver/installed_specification.rb
 - rubygems/resolver/installer_set.rb
 - rubygems/resolver/local_specification.rb
 - rubygems/resolver/lock_set.rb
 - rubygems/resolver/lock_specification.rb
 - rubygems/resolver/molinillo/lib/molinillo.rb
 - rubygems/resolver/molinillo/lib/molinillo/dependency_graph.rb
 - rubygems/resolver/molinillo/lib/molinillo/errors.rb
 - rubygems/resolver/molinillo/lib/molinillo/gem_metadata.rb
 - rubygems/resolver/molinillo/lib/molinillo/modules/specification_provider.rb
 - rubygems/resolver/molinillo/lib/molinillo/modules/ui.rb
 - rubygems/resolver/molinillo/lib/molinillo/resolution.rb
 - rubygems/resolver/molinillo/lib/molinillo/resolver.rb
 - rubygems/resolver/molinillo/lib/molinillo/state.rb
 - rubygems/resolver/requirement_list.rb
 - rubygems/resolver/set.rb
 - rubygems/resolver/source_set.rb
 - rubygems/resolver/spec_specification.rb
 - rubygems/resolver/specification.rb
 - rubygems/resolver/stats.rb
 - rubygems/resolver/vendor_set.rb
 - rubygems/resolver/vendor_specification.rb
 - rubygems/security.rb
 - rubygems/security/policies.rb
 - rubygems/security/policy.rb
 - rubygems/security/signer.rb
 - rubygems/security/trust_dir.rb
 - rubygems/server.rb
 - rubygems/source.rb
 - rubygems/source/git.rb
 - rubygems/source/installed.rb
 - rubygems/source/local.rb
 - rubygems/source/lock.rb
 - rubygems/source/specific_file.rb
 - rubygems/source/vendor.rb
 - rubygems/source_list.rb
 - rubygems/spec_fetcher.rb
 - rubygems/specification.rb
 - rubygems/stub_specification.rb
 - rubygems/syck_hack.rb
 - rubygems/test_case.rb
 - rubygems/test_utilities.rb
 - rubygems/text.rb
 - rubygems/uninstaller.rb
 - rubygems/uri_formatter.rb
 - rubygems/user_interaction.rb
 - rubygems/util.rb
 - rubygems/util/licenses.rb
 - rubygems/util/list.rb
 - rubygems/validator.rb
 - rubygems/version.rb
 - rubygems/version_option.rb
 
Namespace
- MODULE Gem::Commands
 - MODULE Gem::DefaultUserInteraction
 - MODULE Gem::Deprecate
 - MODULE Gem::Ext
 - MODULE Gem::GemcutterUtilities
 - MODULE Gem::InstallUpdateOptions
 - MODULE Gem::LocalRemoteOptions
 - MODULE Gem::RbConfig
 - MODULE Gem::Security
 - MODULE Gem::Text
 - MODULE Gem::UserInteraction
 - MODULE Gem::Util
 - MODULE Gem::VersionOption
 - CLASS Gem::AvailableSet
 - CLASS Gem::BasicSpecification
 - CLASS Gem::Command
 - CLASS Gem::CommandLineError
 - CLASS Gem::CommandManager
 - CLASS Gem::ConfigFile
 - CLASS Gem::ConflictError
 - CLASS Gem::ConsoleUI
 - CLASS Gem::Dependency
 - CLASS Gem::DependencyError
 - CLASS Gem::DependencyInstaller
 - CLASS Gem::DependencyList
 - CLASS Gem::DependencyRemovalException
 - CLASS Gem::DependencyResolutionError
 - CLASS Gem::Doctor
 - CLASS Gem::DocumentError
 - CLASS Gem::EndOfYAMLException
 - CLASS Gem::ErrorReason
 - CLASS Gem::Exception
 - CLASS Gem::FakeFetcher
 - CLASS Gem::FilePermissionError
 - CLASS Gem::FormatException
 - CLASS Gem::GemNotFoundException
 - CLASS Gem::GemNotInHomeException
 - CLASS Gem::GemRunner
 - CLASS Gem::ImpossibleDependenciesError
 - CLASS Gem::Indexer
 - CLASS Gem::InstallError
 - CLASS Gem::Installer
 - CLASS Gem::InstallerTestCase
 - CLASS Gem::InvalidSpecificationException
 - CLASS Gem::Licenses
 - CLASS Gem::List
 - CLASS Gem::LoadError
 - CLASS Gem::MockGemUi
 - CLASS Gem::NameTuple
 - CLASS Gem::NoAliasYAMLTree
 - CLASS Gem::OperationNotSupportedError
 - CLASS Gem::Package
 - CLASS Gem::PackageTask
 - CLASS Gem::PathSupport
 - CLASS Gem::Platform
 - CLASS Gem::PlatformMismatch
 - CLASS Gem::RemoteError
 - CLASS Gem::RemoteFetcher
 - CLASS Gem::RemoteInstallationCancelled
 - CLASS Gem::RemoteInstallationSkipped
 - CLASS Gem::RemoteSourceException
 - CLASS Gem::Request
 - CLASS Gem::RequestSet
 - CLASS Gem::Requirement
 - CLASS Gem::Resolver
 - CLASS Gem::RubyVersionMismatch
 - CLASS Gem::Server
 - CLASS Gem::SilentUI
 - CLASS Gem::Source
 - CLASS Gem::SourceFetchProblem
 - CLASS Gem::SourceList
 - CLASS Gem::SpecFetcher
 - CLASS Gem::SpecificGemNotFoundException
 - CLASS Gem::Specification
 - CLASS Gem::StreamUI
 - CLASS Gem::StubSpecification
 - CLASS Gem::SystemExitException
 - CLASS Gem::TestCase
 - CLASS Gem::Uninstaller
 - CLASS Gem::UnsatisfiableDependencyError
 - CLASS Gem::UriFormatter
 - CLASS Gem::Validator
 - CLASS Gem::VerificationError
 - CLASS Gem::Version
 
Methods
- ::bin_path
 - ::binary_mode
 - ::bindir
 - ::clear_default_specs
 - ::clear_paths
 - ::config_file
 - ::configuration
 - ::configuration=
 - ::datadir
 - ::default_bindir
 - ::default_cert_path
 - ::default_dir
 - ::default_exec_format
 - ::default_ext_dir_for
 - ::default_gems_use_full_paths?
 - ::default_key_path
 - ::default_path
 - ::default_rubygems_dirs
 - ::default_sources
 - ::default_spec_cache_dir
 - ::deflate
 - ::detect_gemdeps
 - ::dir
 - ::done_installing
 - ::ensure_default_gem_subdirectories
 - ::ensure_gem_subdirectories
 - ::find_files
 - ::find_latest_files
 - ::find_unresolved_default_spec
 - ::finish_resolve
 - ::gunzip
 - ::gzip
 - ::host
 - ::host=
 - ::inflate
 - ::install
 - ::latest_rubygems_version
 - ::latest_spec_for
 - ::latest_version_for
 - ::load_env_plugins
 - ::load_path_insert_index
 - ::load_plugins
 - ::load_yaml
 - ::location_of_caller
 - ::marshal_version
 - ::needs
 - ::path
 - ::path_separator
 - ::paths
 - ::paths=
 - ::platforms
 - ::platforms=
 - ::post_build
 - ::post_install
 - ::post_reset
 - ::post_uninstall
 - ::pre_install
 - ::pre_reset
 - ::pre_uninstall
 - ::prefix
 - ::read_binary
 - ::refresh
 - ::register_default_spec
 - ::remove_unresolved_default_spec
 - ::ruby
 - ::ruby=
 - ::ruby_api_version
 - ::ruby_engine
 - ::ruby_version
 - ::rubygems_version
 - ::searcher=
 - ::sources
 - ::sources=
 - ::spec_cache_dir
 - ::suffix_pattern
 - ::suffixes
 - ::time
 - ::try_activate
 - ::ui
 - ::use_gemdeps
 - ::use_paths
 - ::user_dir
 - ::user_home
 - ::win_platform=
 - ::win_platform?
 
Class/Module Index
          ![show/hide quicksearch [+]](./images/find.png)
        
        - Gem::AvailableSet
 - Gem::BasicSpecification
 - Gem::Command
 - Gem::CommandLineError
 - Gem::CommandManager
 - Gem::Commands
 - Gem::Commands::BuildCommand
 - Gem::Commands::CertCommand
 - Gem::Commands::CheckCommand
 - Gem::Commands::CleanupCommand
 - Gem::Commands::ContentsCommand
 - Gem::Commands::DependencyCommand
 - Gem::Commands::EnvironmentCommand
 - Gem::Commands::FetchCommand
 - Gem::Commands::GenerateIndexCommand
 - Gem::Commands::HelpCommand
 - Gem::Commands::InstallCommand
 - Gem::Commands::ListCommand
 - Gem::Commands::LockCommand
 - Gem::Commands::MirrorCommand
 - Gem::Commands::OpenCommand
 - Gem::Commands::OutdatedCommand
 - Gem::Commands::OwnerCommand
 - Gem::Commands::PristineCommand
 - Gem::Commands::PushCommand
 - Gem::Commands::QueryCommand
 - Gem::Commands::RdocCommand
 - Gem::Commands::SearchCommand
 - Gem::Commands::ServerCommand
 - Gem::Commands::SetupCommand
 - Gem::Commands::SourcesCommand
 - Gem::Commands::SpecificationCommand
 - Gem::Commands::StaleCommand
 - Gem::Commands::UninstallCommand
 - Gem::Commands::UnpackCommand
 - Gem::Commands::UpdateCommand
 - Gem::Commands::WhichCommand
 - Gem::Commands::YankCommand
 - Gem::ConfigFile
 - Gem::ConflictError
 - Gem::ConsoleUI
 - Gem::DefaultUserInteraction
 - Gem::Dependency
 - Gem::DependencyError
 - Gem::DependencyInstaller
 - Gem::DependencyList
 - Gem::DependencyRemovalException
 - Gem::DependencyResolutionError
 - Gem::Deprecate
 - Gem::Doctor
 - Gem::DocumentError
 - Gem::EndOfYAMLException
 - Gem::ErrorReason
 - Gem::Exception
 - Gem::Ext
 - Gem::Ext::BuildError
 - Gem::Ext::Builder
 - Gem::Ext::CmakeBuilder
 - Gem::Ext::ConfigureBuilder
 - Gem::Ext::ExtConfBuilder
 - Gem::Ext::RakeBuilder
 - Gem::FakeFetcher
 - Gem::FilePermissionError
 - Gem::FormatException
 - Gem::GemNotFoundException
 - Gem::GemNotInHomeException
 - Gem::GemRunner
 - Gem::GemcutterUtilities
 - Gem::ImpossibleDependenciesError
 - Gem::Indexer
 - Gem::InstallError
 - Gem::InstallUpdateOptions
 - Gem::Installer
 - Gem::Installer::FakePackage
 - Gem::InstallerTestCase
 - Gem::InvalidSpecificationException
 - Gem::Licenses
 - Gem::List
 - Gem::LoadError
 - Gem::LocalRemoteOptions
 - Gem::MockGemUi
 - Gem::MockGemUi::InputEOFError
 - Gem::MockGemUi::SystemExitException
 - Gem::MockGemUi::TTY
 - Gem::MockGemUi::TermError
 - Gem::NameTuple
 - Gem::NoAliasYAMLTree
 - Gem::OperationNotSupportedError
 - Gem::Package::DigestIO
 - Gem::Package::Error
 - Gem::Package::FormatError
 - Gem::Package::NonSeekableIO
 - Gem::Package::Old
 - Gem::Package::PathError
 - Gem::Package::TarHeader
 - Gem::Package::TarInvalidError
 - Gem::Package::TarReader
 - Gem::Package::TarReader::Entry
 - Gem::Package::TarReader::UnexpectedEOF
 - Gem::Package::TarTestCase
 - Gem::Package::TarWriter
 - Gem::Package::TarWriter::BoundedStream
 - Gem::Package::TarWriter::FileOverflow
 - Gem::Package::TarWriter::RestrictedStream
 - Gem::Package::TooLongFileName
 - Gem::PackageTask
 - Gem::PathSupport
 - Gem::Platform
 - Gem::PlatformMismatch
 - Gem::RemoteError
 - Gem::RemoteFetcher
 - Gem::RemoteFetcher::FetchError
 - Gem::RemoteFetcher::UnknownHostError
 - Gem::RemoteInstallationCancelled
 - Gem::RemoteInstallationSkipped
 - Gem::RemoteSourceException
 - Gem::Request::ConnectionPools
 - Gem::Request::ConnectionPools::Net
 - Gem::RequestSet
 - Gem::RequestSet::GemDependencyAPI
 - Gem::RequestSet::Lockfile
 - Gem::RequestSet::Lockfile::ParseError
 - Gem::RequestSet::Lockfile::Parser
 - Gem::RequestSet::Lockfile::Tokenizer
 - Gem::Requirement
 - Gem::Requirement::BadRequirementError
 - Gem::Resolver
 - Gem::Resolver::APISet
 - Gem::Resolver::APISpecification
 - Gem::Resolver::ActivationRequest
 - Gem::Resolver::BestSet
 - Gem::Resolver::ComposedSet
 - Gem::Resolver::Conflict
 - Gem::Resolver::CurrentSet
 - Gem::Resolver::DependencyRequest
 - Gem::Resolver::GitSet
 - Gem::Resolver::GitSpecification
 - Gem::Resolver::IndexSet
 - Gem::Resolver::IndexSpecification
 - Gem::Resolver::InstalledSpecification
 - Gem::Resolver::InstallerSet
 - Gem::Resolver::LocalSpecification
 - Gem::Resolver::LockSet
 - Gem::Resolver::LockSpecification
 - Gem::Resolver::Molinillo
 - Gem::Resolver::Molinillo::CircularDependencyError
 - Gem::Resolver::Molinillo::DependencyGraph
 - Gem::Resolver::Molinillo::DependencyGraph::Vertex
 - Gem::Resolver::Molinillo::DependencyState
 - Gem::Resolver::Molinillo::NoSuchDependencyError
 - Gem::Resolver::Molinillo::PossibilityState
 - Gem::Resolver::Molinillo::ResolutionState
 - Gem::Resolver::Molinillo::Resolver
 - Gem::Resolver::Molinillo::Resolver::Resolution
 - Gem::Resolver::Molinillo::ResolverError
 - Gem::Resolver::Molinillo::SpecificationProvider
 - Gem::Resolver::Molinillo::UI
 - Gem::Resolver::Molinillo::VersionConflict
 - Gem::Resolver::RequirementList
 - Gem::Resolver::Set
 - Gem::Resolver::SourceSet
 - Gem::Resolver::SpecSpecification
 - Gem::Resolver::Specification
 - Gem::Resolver::Stats
 - Gem::Resolver::VendorSet
 - Gem::Resolver::VendorSpecification
 - Gem::RubyVersionMismatch
 - Gem::Security
 - Gem::Security::Exception
 - Gem::Security::Policy
 - Gem::Security::Signer
 - Gem::Security::TrustDir
 - Gem::Server
 - Gem::SilentUI
 - Gem::Source
 - Gem::Source::Git
 - Gem::Source::Installed
 - Gem::Source::Local
 - Gem::Source::Lock
 - Gem::Source::SpecificFile
 - Gem::Source::Vendor
 - Gem::SourceFetchProblem
 - Gem::SourceList
 - Gem::SpecFetcher
 - Gem::SpecificGemNotFoundException
 - Gem::Specification
 - Gem::StreamUI
 - Gem::StreamUI::SilentDownloadReporter
 - Gem::StreamUI::SilentProgressReporter
 - Gem::StreamUI::SimpleProgressReporter
 - Gem::StreamUI::VerboseDownloadReporter
 - Gem::StreamUI::VerboseProgressReporter
 - Gem::StubSpecification
 - Gem::SystemExitException
 - Gem::TestCase
 - Gem::TestCase::SpecFetcherSetup
 - Gem::TestCase::StaticSet
 - Gem::Text
 - Gem::Uninstaller
 - Gem::UnsatisfiableDependencyError
 - Gem::UriFormatter
 - Gem::UserInteraction
 - Gem::Util
 - Gem::Validator
 - Gem::VerificationError
 - Gem::Version
 - Gem::VersionOption
 - Kernel
 - Object
 - OpenSSL
 - TempIO
 - YAML::Syck
 - YAML::Syck
 
Gem
RubyGems is the Ruby standard for publishing and managing third party libraries.
For user documentation, see:
- 
gem helpandgem help [command] 
For gem developer documentation see:
- 
Gem::Version for version dependency notes
 
Further RubyGems documentation can be found at:
- 
RubyGems API (also available from
gem server) 
RubyGems Plugins¶ ↑
As of RubyGems 1.3.2, RubyGems will load plugins installed in gems 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 discovered via ::find_files then loaded. Take care when implementing a plugin as your plugin file may be loaded multiple times if multiple versions of your gem are installed.
For an example plugin, see the graph gem which adds a `gem graph` command.
RubyGems Defaults, Packaging¶ ↑
RubyGems defaults are stored in 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 and post install and uninstall hooks. See ::pre_install, ::pre_uninstall, ::post_install, ::post_uninstall.
Bugs¶ ↑
You can submit bugs to the RubyGems 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!)
See LICENSE.txt for permissions.
Thanks!
-The RubyGems Team
frozen_string_literal: true
frozen_string_literal: true
frozen_string_literal: true
frozen_string_literal: true
Constants
- DEFAULT_HOST
 - GEM_DEP_FILES
 - LOADED_SPECS_MUTEX
 - MARSHAL_SPEC_DIR
 Location of Marshal quick gemspecs on remote repositories
- RDoc
 - REPOSITORY_DEFAULT_GEM_SUBDIRECTORIES
 Subdirectories in a gem repository for default gems
- REPOSITORY_SUBDIRECTORIES
 Subdirectories in a gem repository
- RUBYGEMS_DIR
 - VERSION
 - WIN_PATTERNS
 An Array of Regexps that match windows Ruby platforms.
Attributes
The list of hooks to be run after Gem::DependencyInstaller installs a set of gems
GemDependencyAPI object, which is set when .use_gemdeps is called. This contains all the information from the Gemfile.
The list of hooks to be run after Gem::Installer#install extracts files and builds extensions
The list of hooks to be run after Gem::Installer#install completes installation
The list of hooks to be run after Gem::Uninstaller#uninstall completes installation
Public Class Methods
Find the full path to the executable for gem name.  If the
exec_name is not given, the gem’s default_executable is
chosen, otherwise the specified executable’s path is returned. 
requirements allows you to specify specific gem versions.
 
               # File rubygems.rb, line 224
def self.bin_path(name, exec_name = nil, *requirements)
  # TODO: fails test_self_bin_path_bin_file_gone_in_latest
  # Gem::Specification.find_by_name(name, *requirements).bin_file exec_name
  raise ArgumentError, "you must supply exec_name" unless exec_name
  requirements = Gem::Requirement.default if
    requirements.empty?
  dep = Gem::Dependency.new name, requirements
  loaded = Gem.loaded_specs[name]
  return loaded.bin_file exec_name if loaded && dep.matches_spec?(loaded)
  specs = dep.matching_specs(true)
  raise Gem::GemNotFoundException,
        "can't find gem #{dep}" if specs.empty?
  specs = specs.find_all { |spec|
    spec.executables.include? exec_name
  } if exec_name
  unless spec = specs.last
    msg = "can't find gem #{name} (#{requirements}) with executable #{exec_name}"
    raise Gem::GemNotFoundException, msg
  end
  spec.bin_file exec_name
end
             
            The mode needed to read a file as straight binary.
 
               # File rubygems.rb, line 259
def self.binary_mode
  'rb'
end
             
            The path where gem executables are to be installed.
 
               # File rubygems.rb, line 266
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
             
            Clear default gem related variables. It is for test
 
               # File rubygems.rb, line 1157
def clear_default_specs
  @path_to_default_spec_map.clear
end
             
            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.
 
               # File rubygems.rb, line 277
def self.clear_paths
  @paths         = nil
  @user_home     = nil
  Gem::Specification.reset
  Gem::Security.reset if defined?(Gem::Security)
end
             
            The path to standard location of the user’s .gemrc file.
 
               # File rubygems.rb, line 287
def self.config_file
  @config_file ||= File.join Gem.user_home, '.gemrc'
end
             
            The standard configuration object for gems.
 
               # File rubygems.rb, line 294
def self.configuration
  @configuration ||= Gem::ConfigFile.new []
end
             
            Use the given configuration object (which implements the ConfigFile protocol) as the standard configuration object.
 
               # File rubygems.rb, line 302
def self.configuration=(config)
  @configuration = config
end
             
            The path to the data directory specified by the gem name. If the package is not available as a gem, return nil.
 
               # File rubygems.rb, line 310
  def self.datadir(gem_name)
# TODO: deprecate
    spec = @loaded_specs[gem_name]
    return nil if spec.nil?
    spec.datadir
  end
             
            The default directory for binaries
 
               # File rubygems/defaults.rb, line 117
def self.default_bindir
  if defined? RUBY_FRAMEWORK_VERSION then # mac framework support
    '/usr/bin'
  else # generic install
    RbConfig::CONFIG['bindir']
  end
end
             
            The default signing certificate chain path
 
               # File rubygems/defaults.rb, line 146
def self.default_cert_path
  File.join Gem.user_home, ".gem", "gem-public_cert.pem"
end
             
            Default home directory path to be used if an alternate value is not specified in the environment
 
               # File rubygems/defaults.rb, line 30
def self.default_dir
  path = if defined? RUBY_FRAMEWORK_VERSION then
           [
             File.dirname(RbConfig::CONFIG['sitedir']),
             'Gems',
             RbConfig::CONFIG['ruby_version']
           ]
         elsif RbConfig::CONFIG['rubylibprefix'] then
           [
            RbConfig::CONFIG['rubylibprefix'],
            'gems',
            RbConfig::CONFIG['ruby_version']
           ]
         else
           [
             RbConfig::CONFIG['libdir'],
             ruby_engine,
             'gems',
             RbConfig::CONFIG['ruby_version']
           ]
         end
  @default_dir ||= File.join(*path)
end
             
            Deduce Ruby’s –program-prefix and –program-suffix from its install name
 
               # File rubygems/defaults.rb, line 103
def self.default_exec_format
  exec_format = RbConfig::CONFIG['ruby_install_name'].sub('ruby', '%s') rescue '%s'
  unless exec_format =~ /%s/ then
    raise Gem::Exception,
      "[BUG] invalid exec_format #{exec_format.inspect}, no %s"
  end
  exec_format
end
             
            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
 
               # File rubygems/defaults.rb, line 62
def self.default_ext_dir_for base_dir
  nil
end
             
            Whether to expect full paths in default gems - true for non-MRI ruby implementations
 
               # File rubygems/defaults.rb, line 153
def self.default_gems_use_full_paths?
  ruby_engine != 'ruby'
end
             
            The default signing key path
 
               # File rubygems/defaults.rb, line 139
def self.default_key_path
  File.join Gem.user_home, ".gem", "gem-private_key.pem"
end
             
            Default gem load path
 
               # File rubygems/defaults.rb, line 92
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
             
            Paths where RubyGems’ .rb files and bin files are installed
 
               # File rubygems/defaults.rb, line 69
def self.default_rubygems_dirs
  nil # default to standard layout
end
             
            An Array of the default sources that come with RubyGems
 
               # File rubygems/defaults.rb, line 14
def self.default_sources
  %w[https://rubygems.org/]
end
             
            Default spec directory path to be used if an alternate value is not specified in the environment
 
               # File rubygems/defaults.rb, line 22
def self.default_spec_cache_dir
  File.join Gem.user_home, '.gem', 'specs'
end
             
            A Zlib::Deflate.deflate wrapper
 
               # File rubygems.rb, line 320
def self.deflate(data)
  require 'zlib'
  Zlib::Deflate.deflate data
end
             
            The path where gems are to be installed.
 
               # File rubygems.rb, line 347
def self.dir
  paths.home
end
             
            Adds a post-installs hook that will be passed a Gem::DependencyInstaller and a list of installed specifications when Gem::DependencyInstaller#install is complete
 
               # File rubygems.rb, line 703
def self.done_installing(&hook)
  @done_installing_hooks << hook
end
             
            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.
 
               # File rubygems.rb, line 381
def self.ensure_default_gem_subdirectories dir = Gem.dir, mode = nil
  ensure_subdirectories(dir, mode, REPOSITORY_DEFAULT_GEM_SUBDIRECTORIES)
end
             
            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.
 
               # File rubygems.rb, line 368
def self.ensure_gem_subdirectories dir = Gem.dir, mode = nil
  ensure_subdirectories(dir, mode, REPOSITORY_SUBDIRECTORIES)
end
             
            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
 
               # File rubygems.rb, line 428
def self.find_files(glob, check_load_path=true)
  files = []
  files = find_files_from_load_path glob if check_load_path
  files.concat Gem::Specification.stubs.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
             
            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.
 
               # File rubygems.rb, line 462
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 a Gem::Specification of default
gem from path
 
               # File rubygems.rb, line 1136
def find_unresolved_default_spec(path)
  Gem.suffixes.each do |suffix|
    spec = @path_to_default_spec_map["#{path}#{suffix}"]
    return spec if spec
  end
  nil
end
             
             
               # File rubygems.rb, line 210
def self.finish_resolve(request_set=Gem::RequestSet.new)
  request_set.import Gem::Specification.unresolved_deps.values
  request_set.resolve_current.each do |s|
    s.full_spec.activate
  end
end
             
            Zlib::GzipReader wrapper that unzips data.
 
               # File rubygems.rb, line 523
def self.gunzip(data)
  require 'rubygems/util'
  Gem::Util.gunzip data
end
             
            Zlib::GzipWriter wrapper that zips data.
 
               # File rubygems.rb, line 531
def self.gzip(data)
  require 'rubygems/util'
  Gem::Util.gzip data
end
             
            Get the default RubyGems API host. This is normally
https://rubygems.org.
 
               # File rubygems.rb, line 563
def self.host
  # TODO: move to utils
  @host ||= Gem::DEFAULT_HOST
end
             
            Set the default RubyGems API host.
 
               # File rubygems.rb, line 570
def self.host= host
  # TODO: move to utils
  @host = host
end
             
            A Zlib::Inflate#inflate wrapper
 
               # File rubygems.rb, line 539
def self.inflate(data)
  require 'rubygems/util'
  Gem::Util.inflate data
end
             
            Top level install helper method. Allows you to install gems interactively:
% irb >> Gem.install "minitest" Fetching: minitest-3.0.1.gem (100%) => [#<Gem::Specification:0x1013b4528 @name="minitest", ...>]
 
               # File rubygems.rb, line 552
def self.install name, version = Gem::Requirement.default, *options
  require "rubygems/dependency_installer"
  inst = Gem::DependencyInstaller.new(*options)
  inst.install name, version
  inst.installed_gems
end
             
            Returns the latest release version of RubyGems.
 
               # File rubygems.rb, line 831
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
             
            Returns the latest release-version specification for the gem
name.
 
               # File rubygems.rb, line 818
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
             
            Returns the version of the latest release-version of gem name
 
               # File rubygems.rb, line 839
def self.latest_version_for name
  spec = latest_spec_for name
  spec and spec.version
end
             
            Find all ‘rubygems_plugin’ files in $LOAD_PATH and load them
 
               # File rubygems.rb, line 1002
def self.load_env_plugins
  path = "rubygems_plugin"
  files = []
  $LOAD_PATH.each do |load_path|
    globbed = Dir["#{File.expand_path path, load_path}#{Gem.suffix_pattern}"]
    globbed.each do |load_path_file|
      files << load_path_file if File.file?(load_path_file.untaint)
    end
  end
  load_plugin_files files
end
             
            The index to insert activated gem paths into the $LOAD_PATH. The activated gem’s paths are inserted before site lib directory by default.
 
               # File rubygems.rb, line 579
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
end
             
            Find the ‘rubygems_plugin’ files in the latest installed gems and load them
 
               # File rubygems.rb, line 990
def self.load_plugins
  # Remove this env var by at least 3.0
  if ENV['RUBYGEMS_LOAD_ALL_PLUGINS']
    load_plugin_files find_files('rubygems_plugin', false)
  else
    load_plugin_files find_latest_files('rubygems_plugin', false)
  end
end
             
            Loads YAML, preferring Psych
 
               # File rubygems.rb, line 594
def self.load_yaml
  return if @yaml_loaded
  return unless defined?(gem)
  test_syck = ENV['TEST_SYCK']
  # Only Ruby 1.8 and 1.9 have syck
  test_syck = false unless /^1\./ =~ RUBY_VERSION
  unless test_syck
    begin
      gem 'psych', '>= 1.2.1'
    rescue Gem::LoadError
      # It's OK if the user does not have the psych gem installed.  We will
      # attempt to require the stdlib version
    end
    begin
      # Try requiring the gem version *or* stdlib version of psych.
      require 'psych'
    rescue ::LoadError
      # If we can't load psych, thats fine, go on.
    else
      # If 'yaml' has already been required, then we have to
      # be sure to switch it over to the newly loaded psych.
      if defined?(YAML::ENGINE) && YAML::ENGINE.yamler != "psych"
        YAML::ENGINE.yamler = "psych"
      end
      require 'rubygems/psych_additions'
      require 'rubygems/psych_tree'
    end
  end
  require 'yaml'
  # If we're supposed to be using syck, then we may have to force
  # activate it via the YAML::ENGINE API.
  if test_syck and defined?(YAML::ENGINE)
    YAML::ENGINE.yamler = "syck" unless YAML::ENGINE.syck?
  end
  # Now that we're sure some kind of yaml library is loaded, pull
  # in our hack to deal with Syck's DefaultKey ugliness.
  require 'rubygems/syck_hack'
  @yaml_loaded = true
end
             
            The file name and line number of the caller of the caller of this method.
 
               # File rubygems.rb, line 646
def self.location_of_caller
  caller[1] =~ /(.*?):(\d+).*?$/i
  file = $1
  lineno = $2.to_i
  [file, lineno]
end
             
            The version of the Marshal format for your Ruby.
 
               # File rubygems.rb, line 657
def self.marshal_version
  "#{Marshal::MAJOR_VERSION}.#{Marshal::MINOR_VERSION}"
end
             
             
               # File rubygems.rb, line 202
def self.needs
  rs = Gem::RequestSet.new
  yield rs
  finish_resolve rs
end
             
            How String Gem paths should be split. Overridable for esoteric platforms.
 
               # File rubygems/defaults.rb, line 85
def self.path_separator
  File::PATH_SEPARATOR
end
             
            Retrieve the PathSupport object that RubyGems uses to lookup files.
 
               # File rubygems.rb, line 328
def self.paths
  @paths ||= Gem::PathSupport.new
end
             
            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’
 
               # File rubygems.rb, line 336
def self.paths=(env)
  clear_paths
  @paths = Gem::PathSupport.new env
  Gem::Specification.dirs = @paths.path
end
             
            Array of platforms this RubyGems supports.
 
               # File rubygems.rb, line 671
def self.platforms
  @platforms ||= []
  if @platforms.empty?
    @platforms = [Gem::Platform::RUBY, Gem::Platform.local]
  end
  @platforms
end
             
            Set array of platforms this RubyGems supports (primarily for testing).
 
               # File rubygems.rb, line 664
def self.platforms=(platforms)
  @platforms = platforms
end
             
            Adds a post-build hook that will be passed an Gem::Installer instance when Gem::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.
 
               # File rubygems.rb, line 686
def self.post_build(&hook)
  @post_build_hooks << hook
end
             
            Adds a post-install hook that will be passed an Gem::Installer instance when Gem::Installer#install is called
 
               # File rubygems.rb, line 694
def self.post_install(&hook)
  @post_install_hooks << hook
end
             
            Adds a hook that will get run after Gem::Specification.reset is run.
 
               # File rubygems.rb, line 711
def self.post_reset(&hook)
  @post_reset_hooks << hook
end
             
            Adds a post-uninstall hook that will be passed a Gem::Uninstaller instance and the spec that was uninstalled when Gem::Uninstaller#uninstall is called
 
               # File rubygems.rb, line 720
def self.post_uninstall(&hook)
  @post_uninstall_hooks << hook
end
             
            Adds a pre-install hook that will be passed an Gem::Installer instance when Gem::Installer#install is
called.  If the hook returns false then the install will be
aborted.
 
               # File rubygems.rb, line 729
def self.pre_install(&hook)
  @pre_install_hooks << hook
end
             
            Adds a hook that will get run before Gem::Specification.reset is run.
 
               # File rubygems.rb, line 737
def self.pre_reset(&hook)
  @pre_reset_hooks << hook
end
             
            Adds a pre-uninstall hook that will be passed an Gem::Uninstaller instance and the spec that will be uninstalled when Gem::Uninstaller#uninstall is called
 
               # File rubygems.rb, line 746
def self.pre_uninstall(&hook)
  @pre_uninstall_hooks << hook
end
             
            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.
 
               # File rubygems.rb, line 755
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) then
    prefix
  end
end
             
            Safely read a file in binary mode on all platforms.
 
               # File rubygems.rb, line 775
def self.read_binary(path)
  open path, 'rb+' do |f|
    f.flock(File::LOCK_EX)
    f.read
  end
rescue Errno::EACCES
  open path, 'rb' do |f|
    f.read
  end
rescue Errno::ENOLCK # NFS
  if Thread.main != Thread.current
    raise
  else
    open path, 'rb' do |f|
      f.read
    end
  end
end
             
            Refresh available gems from disk.
 
               # File rubygems.rb, line 768
def self.refresh
  Gem::Specification.reset
end
             
            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.
 
 
               # File rubygems.rb, line 1115
def register_default_spec(spec)
  new_format = Gem.default_gems_use_full_paths? || spec.require_paths.any? {|path| spec.files.any? {|f| f.start_with? path } }
  if new_format
    prefix_group = spec.require_paths.map {|f| f + "/"}.join("|")
    prefix_pattern = /^(#{prefix_group})/
  end
  spec.files.each do |file|
    if new_format
      file = file.sub(prefix_pattern, "")
      next unless $~
    end
    @path_to_default_spec_map[file] = spec
  end
end
             
            Remove needless Gem::Specification of default gem from unresolved default gem list
 
               # File rubygems.rb, line 1148
def remove_unresolved_default_spec(spec)
  spec.files.each do |file|
    @path_to_default_spec_map.delete(file)
  end
end
             
            The path to the running Ruby interpreter.
 
               # File rubygems.rb, line 797
def self.ruby
  if @ruby.nil? then
    @ruby = File.join(RbConfig::CONFIG['bindir'],
                      "#{RbConfig::CONFIG['ruby_install_name']}#{RbConfig::CONFIG['EXEEXT']}")
    @ruby = "\"#{@ruby}\"" if @ruby =~ /\s/
  end
  @ruby
end
             
            Allows setting path to Ruby. This method is available when requiring ‘rubygems/test_case’
 
               # File rubygems/test_case.rb, line 65
def self.ruby= ruby
  @ruby = ruby
end
             
            Returns a String containing the API compatibility version of Ruby
 
               # File rubygems.rb, line 811
def self.ruby_api_version
  @ruby_api_version ||= RbConfig::CONFIG['ruby_version'].dup
end
             
            A wrapper around RUBY_ENGINE const that may not be defined
 
               # File rubygems/defaults.rb, line 128
def self.ruby_engine
  if defined? RUBY_ENGINE then
    RUBY_ENGINE
  else
    'ruby'
  end
end
             
            A Gem::Version for the currently running Ruby.
 
               # File rubygems.rb, line 847
def self.ruby_version
  return @ruby_version if defined? @ruby_version
  version = RUBY_VERSION.dup
  if defined?(RUBY_PATCHLEVEL) && RUBY_PATCHLEVEL != -1 then
    version << ".#{RUBY_PATCHLEVEL}"
  elsif defined?(RUBY_REVISION) then
    version << ".dev.#{RUBY_REVISION}"
  end
  @ruby_version = Gem::Version.new version
end
             
            A Gem::Version for the currently running RubyGems
 
               # File rubygems.rb, line 863
def self.rubygems_version
  return @rubygems_version if defined? @rubygems_version
  @rubygems_version = Gem::Version.new Gem::VERSION
end
             
            Allows setting the gem path searcher. This method is available when requiring ‘rubygems/test_case’
 
               # File rubygems/test_case.rb, line 49
def self.searcher=(searcher)
  @searcher = searcher
end
             
            Returns an Array of sources to fetch remote gems from. Uses ::default_sources if the sources list is empty.
 
               # File rubygems.rb, line 872
def self.sources
  @sources ||= Gem::SourceList.from(default_sources)
end
             
            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.
 
               # File rubygems.rb, line 883
def self.sources= new_sources
  if !new_sources
    @sources = nil
  else
    @sources = Gem::SourceList.from(new_sources)
  end
end
             
            Glob pattern for require-able path suffixes.
 
               # File rubygems.rb, line 894
def self.suffix_pattern
  @suffix_pattern ||= "{#{suffixes.join(',')}}"
end
             
            Suffixes for require-able paths.
 
               # File rubygems.rb, line 901
def self.suffixes
  @suffixes ||= ['',
                 '.rb',
                 *%w(DLEXT DLEXT2).map { |key|
                   val = RbConfig::CONFIG[key]
                   next unless val and not val.empty?
                   ".#{val}"
                 }
                ].compact.uniq
end
             
            Prints the amount of time the supplied block takes to run using the debug UI output.
 
               # File rubygems.rb, line 916
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 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.
 
               # File rubygems.rb, line 182
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 # this could fail due to gem dep collisions, go lax
    Gem::Specification.find_by_name(spec.name).activate
  end
  return true
end
             
            Lazily loads DefaultUserInteraction and returns the default UI.
 
               # File rubygems.rb, line 931
def self.ui
  require 'rubygems/user_interaction'
  Gem::DefaultUserInteraction.ui
end
             
            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.
 
               # File rubygems.rb, line 1037
def self.use_gemdeps path = nil
  raise_exception = path
  path ||= ENV['RUBYGEMS_GEMDEPS']
  return unless path
  path = path.dup
  if path == "-" then
    require 'rubygems/util'
    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.untaint
  unless File.file? path then
    return unless raise_exception
    raise ArgumentError, "Unable to find gem dependencies file at #{path}"
  end
  rs = Gem::RequestSet.new
  @gemdeps = rs.load_gemdeps path
  rs.resolve_current.map do |s|
    sp = s.full_spec
    sp.activate
    sp
  end
rescue Gem::LoadError, Gem::UnsatisfiableDependencyError => e
  warn e.message
  warn "You may need to `gem install -g` to install missing gems"
  warn ""
end
             
            Use the home and paths values for ::dir and ::path.  Used mainly by the unit tests to
provide environment isolation.
 
               # File rubygems.rb, line 941
def self.use_paths(home, *paths)
  paths = nil if paths == [nil]
  paths = paths.first if Array === Array(paths).first
  self.paths = { "GEM_HOME" => home, "GEM_PATH" => paths }
end
             
            Path for gems in the user’s home directory
 
               # File rubygems/defaults.rb, line 76
def self.user_dir
  parts = [Gem.user_home, '.gem', ruby_engine]
  parts << RbConfig::CONFIG['ruby_version'] unless RbConfig::CONFIG['ruby_version'].empty?
  File.join parts
end
             
            The home directory for the user.
 
               # File rubygems.rb, line 950
def self.user_home
  @user_home ||= find_home.untaint
end