module Gem - Documentation for Ruby 3.4
Description: module Gem: RubyGems is the Ruby standard for publishing and managing third party libraries. guides.
Keywords: ruby,module,Gem

# module Gem

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

For user documentation, see:

- `gem help` and `gem help [command]`

- RubyGems User Guide

- Frequently Asked Questions

For gem developer documentation see:

- Creating Gems

- `Gem::Specification`

- `Gem::Version` for version dependency notes

Further RubyGems documentation can be found at:

- RubyGems Guides

- RubyGems API (also available from `gem server`)

## 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 `Gem::pre_install`, `Gem::pre_uninstall`, `Gem::post_install`, `Gem::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!)

## License¶ ↑

See LICENSE.txt for permissions.

Thanks!

-The RubyGems Team

Provides 3 methods for declaring when something is going away.

+deprecate(name, repl, year, month)+:

    Indicate something may be removed on/after a certain date.

+rubygems_deprecate(name, replacement=:none)+:

    Indicate something will be removed in the next major RubyGems version,
    and (optionally) a replacement for it.

`rubygems_deprecate_command`:

    Indicate a RubyGems command (in +lib/rubygems/commands/*.rb+) will be
    removed in the next RubyGems version.

Also provides `skip_during` for temporarily turning off deprecation warnings. This is intended to be used in the test suite, so deprecation warnings don’t cause test failures if you need to make sure stderr is otherwise empty.

Example usage of `deprecate` and `rubygems_deprecate`:

    class Legacy
      def self.some_class_method
        # ...
      end

      def some_instance_method
        # ...
      end

      def some_old_method
        # ...
      end

      extend Gem::Deprecate
      deprecate :some_instance_method, "X.z", 2011, 4
      rubygems_deprecate :some_old_method, "Modern#some_new_method"

      class << self
        extend Gem::Deprecate
        deprecate :some_class_method, :none, 2011, 4
      end
    end

Example usage of `rubygems_deprecate_command`:

    class Gem::Commands::QueryCommand < Gem::Command
      extend Gem::Deprecate
      rubygems_deprecate_command

      # ...
    end

Example usage of `skip_during`:

    class TestSomething < Gem::Testcase
      def test_some_thing_with_deprecations
        Gem::Deprecate.skip_during do
          actual_stdout, actual_stderr = capture_output do
            Gem.something_deprecated
          end
          assert_empty actual_stdout
          assert_equal(expected, actual_stderr)
        end
      end
    end

### Constants

DEFAULT_HOST
DEFAULT_SOURCE_DATE_EPOCH

  The default value for SOURCE_DATE_EPOCH if not specified. We want a date after 1980-01-01, to prevent issues with Zip files. This particular timestamp is for 1980-01-02 00:00:00 GMT.

GEM_DEP_FILES
LOADED_SPECS_MUTEX
MARSHAL_SPEC_DIR

  Location of `Marshal` quick gemspecs on remote repositories

RDoc

  We define the following two similar name classes in this file:

  - `RDoc::RubyGemsHook`

  - `RDoc::RubygemsHook`

  `RDoc::RubyGemsHook` is the main class that has real logic.

  `RDoc::RubygemsHook` is a class that is only for compatibility. `RDoc::RubygemsHook` is used by RubyGems directly. We can remove this when all maintained RubyGems remove ‘rubygems/rdoc.rb`.

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

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.

discover_gems_on_require [RW]

Whether RubyGems should enhance builtin ‘require` to automatically check whether the path required is present in installed gems, and automatically activate them and add them to `$LOAD_PATH`.

done_installing_hooks [R]

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

gemdeps [R]

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

loaded_specs [R]

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

post_build_hooks [R]

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

post_install_hooks [R]

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

post_reset_hooks [R]

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

post_uninstall_hooks [R]

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

pre_install_hooks [R]

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

pre_reset_hooks [R]

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

pre_uninstall_hooks [R]

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

### Public Class Methods

activated_gem_paths ()
Source

    # File lib/rubygems.rb, line 599
    def self.activated_gem_paths
      @activated_gem_paths ||= 0
    end

The number of paths in the +$LOAD_PATH+ from activated gems. Used to prioritize `-I` and `ENV['RUBYLIB']` entries during `require`.

add_to_load_path (*paths)
Source

    # File lib/rubygems.rb, line 606
    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

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

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

    # File lib/rubygems.rb, line 245
    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

`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.

binary_mode ()
Source

    # File lib/rubygems.rb, line 299
    def self.binary_mode
      "rb"
    end

The mode needed to read a file as straight binary.

bindir (install_dir=Gem.dir)
Source

    # File lib/rubygems.rb, line 306
    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

The path where gem executables are to be installed.

cache_home ()
Source

    # File lib/rubygems/defaults.rb, line 147
    def self.cache_home
      @cache_home ||= ENV["XDG_CACHE_HOME"] || File.join(Gem.user_home, ".cache")
    end

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

clear_default_specs ()
Source

    # File lib/rubygems.rb, line 1280
    def clear_default_specs
      @path_to_default_spec_map.clear
    end

Clear default gem related variables. It is for test

clear_paths ()
Source

    # File lib/rubygems.rb, line 324
    def self.clear_paths
      @paths         = nil
      @user_home     = nil
      Gem::Specification.reset
      Gem::Security.reset if defined?(Gem::Security)
    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.

config_file ()
Source

    # File lib/rubygems/defaults.rb, line 133
    def self.config_file
      @config_file ||= find_config_file
    end

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

config_home ()
Source

    # File lib/rubygems/defaults.rb, line 114
    def self.config_home
      @config_home ||= ENV["XDG_CONFIG_HOME"] || File.join(Gem.user_home, ".config")
    end

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

configuration ()
Source

    # File lib/rubygems.rb, line 334
    def self.configuration
      @configuration ||= Gem::ConfigFile.new []
    end

The standard configuration object for gems.

configuration= (config)
Source

    # File lib/rubygems.rb, line 342
    def self.configuration=(config)
      @configuration = config
    end

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

data_home ()
Source

    # File lib/rubygems/defaults.rb, line 154
    def self.data_home
      @data_home ||= ENV["XDG_DATA_HOME"] || File.join(Gem.user_home, ".local", "share")
    end

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

default_bindir ()
Source

    # File lib/rubygems/defaults.rb, line 204
    def self.default_bindir
      RbConfig::CONFIG["bindir"]
    end

The default directory for binaries

default_cert_path ()
Source

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

The default signing certificate chain path

default_dir ()
Source

    # File lib/rubygems/defaults.rb, line 37
    def self.default_dir
      @default_dir ||= File.join(RbConfig::CONFIG["rubylibprefix"], "gems", RbConfig::CONFIG["ruby_version"])
    end

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

default_exec_format ()
Source

    # File lib/rubygems/defaults.rb, line 186
    def self.default_exec_format
      exec_format = begin
                      RbConfig::CONFIG["ruby_install_name"].sub("ruby", "%s")
                    rescue StandardError
                      "%s"
                    end

      unless exec_format.include?("%s")
        raise Gem::Exception,
          "[BUG] invalid exec_format #{exec_format.inspect}, no %s"
      end

      exec_format
    end

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

default_ext_dir_for (base_dir)
Source

    # File lib/rubygems/defaults.rb, line 48
    def self.default_ext_dir_for(base_dir)
      nil
    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

default_key_path ()
Source

    # File lib/rubygems/defaults.rb, line 215
    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

The default signing key path

default_path ()
Source

    # File lib/rubygems/defaults.rb, line 175
    def self.default_path
      path = []
      path << user_dir if user_home && File.exist?(user_home)
      path << default_dir
      path << vendor_dir if vendor_dir && File.directory?(vendor_dir)
      path
    end

Default gem load path

default_rubygems_dirs ()
Source

    # File lib/rubygems/defaults.rb, line 55
    def self.default_rubygems_dirs
      nil # default to standard layout
    end

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

default_sources ()
Source

    # File lib/rubygems/defaults.rb, line 15
    def self.default_sources
      %w[https://rubygems.org/]
    end

An `Array` of the default sources that come with RubyGems

default_spec_cache_dir ()
Source

    # File lib/rubygems/defaults.rb, line 23
    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.cache_home, "gem", "specs"
      end

      default_spec_cache_dir
    end

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

default_specifications_dir ()
Source

    # File lib/rubygems/defaults.rb, line 62
    def self.default_specifications_dir
      @default_specifications_dir ||= File.join(Gem.default_dir, "specifications", "default")
    end

Path to specification files of default gems.

deflate (data)
Source

    # File lib/rubygems.rb, line 349
    def self.deflate(data)
      require "zlib"
      Zlib::Deflate.deflate data
    end

A `Zlib::Deflate.deflate` wrapper

dir ()
Source

    # File lib/rubygems.rb, line 397
    def self.dir
      paths.home
    end

The path where gems are to be installed.

done_installing (&hook)
Source

    # File lib/rubygems.rb, line 710
    def self.done_installing(&hook)
      @done_installing_hooks << hook
    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

dynamic_library_suffixes ()
Source

    # File lib/rubygems.rb, line 991
    def self.dynamic_library_suffixes
      @dynamic_library_suffixes ||= suffixes - [".rb"]
    end

Suffixes for dynamic library require-able paths.

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

    # File lib/rubygems.rb, line 448
    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 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.

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

    # File lib/rubygems.rb, line 435
    def self.ensure_gem_subdirectories(dir = Gem.dir, mode = nil)
      ensure_subdirectories(dir, mode, REPOSITORY_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.

env_requirement (gem_name)
Source

    # File lib/rubygems.rb, line 859
    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"
        Gem::Requirement.create(req)
      end
    end

find_config_file ()
Source

    # File lib/rubygems/defaults.rb, line 121
    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

Finds the user’s config file

find_default_spec (path)
Source

    # File lib/rubygems.rb, line 1265
    def find_default_spec(path)
      @path_to_default_spec_map[path]
    end

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

find_files (glob, check_load_path=true)
Source

    # File lib/rubygems.rb, line 499
    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.flat_map {|spec|
        spec.matches_for_glob("#{glob}#{Gem.suffix_pattern}")
      }

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

      files
    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`

find_latest_files (glob, check_load_path=true)
Source

    # File lib/rubygems.rb, line 536
    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).flat_map {|spec|
        spec.matches_for_glob("#{glob}#{Gem.suffix_pattern}")
      }

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

      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.

find_unresolved_default_spec (path)
Source

    # File lib/rubygems.rb, line 1272
    def find_unresolved_default_spec(path)
      default_spec = @path_to_default_spec_map[path]
      default_spec if default_spec && loaded_specs[default_spec.name] != default_spec
    end

`Find` an unresolved `Gem::Specification` of default gem from `path`

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

    # File lib/rubygems.rb, line 230
    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

freebsd_platform? ()
Source

    # File lib/rubygems.rb, line 1061
    def self.freebsd_platform?
      RbConfig::CONFIG["host_os"].to_s.include?("bsd")
    end

Is this platform FreeBSD

host ()
Source

    # File lib/rubygems.rb, line 571
    def self.host
      @host ||= Gem::DEFAULT_HOST
    end

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

host= (host)
Source

    # File lib/rubygems.rb, line 577
    def self.host=(host)
      @host = host
    end

Set the default RubyGems API host.

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

    # File lib/rubygems.rb, line 560
    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

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

    % irb
    >> Gem.install "minitest"
    Fetching: minitest-5.14.0.gem (100%)
    => [#<Gem::Specification:0x1013b4528 @name="minitest", ...>]

java_platform? ()
Source

    # File lib/rubygems.rb, line 1047
    def self.java_platform?
      RUBY_PLATFORM == "java"
    end

Is this a java platform?

latest_rubygems_version ()
Source

    # File lib/rubygems.rb, line 884
    def self.latest_rubygems_version
      latest_version_for("rubygems-update") ||
        raise("Can't find 'rubygems-update' in any repo. Check `gem source list`.")
    end

Returns the latest release version of RubyGems.

latest_spec_for (name)
Source

    # File lib/rubygems.rb, line 871
    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.last

      spec
    end

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

latest_version_for (name)
Source

    # File lib/rubygems.rb, line 892
    def self.latest_version_for(name)
      latest_spec_for(name)&.version
    end

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

load_env_plugins ()
Source

    # File lib/rubygems.rb, line 1096
    def self.load_env_plugins
      load_plugin_files find_files_from_load_path("rubygems_plugin")
    end

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

load_path_insert_index ()
Source

    # File lib/rubygems.rb, line 585
    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

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

load_plugins ()
Source

    # File lib/rubygems.rb, line 1087
    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

`Find` rubygems plugin files in the standard location and load them

load_safe_marshal ()
Source

    # File lib/rubygems.rb, line 631
    def self.load_safe_marshal
      return if @safe_marshal_loaded

      require_relative "rubygems/safe_marshal"

      @safe_marshal_loaded = true
    end

load_yaml ()
Source

    # File lib/rubygems.rb, line 618
    def self.load_yaml
      return if @yaml_loaded

      require "psych"
      require_relative "rubygems/psych_tree"

      require_relative "rubygems/safe_yaml"

      @yaml_loaded = true
    end

Loads `YAML`, preferring `Psych`

location_of_caller (depth = 1)
Source

    # File lib/rubygems.rb, line 653
    def self.location_of_caller(depth = 1)
      caller[depth] =~ /(.*?):(\d+).*?$/i
      file = $1
      lineno = $2.to_i

      [file, lineno]
    end

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

marshal_version ()
Source

    # File lib/rubygems.rb, line 664
    def self.marshal_version
      "#{Marshal::MAJOR_VERSION}.#{Marshal::MINOR_VERSION}"
    end

The version of the `Marshal` format for your Ruby.

needs () { |rs| ... }
Source

    # File lib/rubygems.rb, line 222
    def self.needs
      rs = Gem::RequestSet.new

      yield rs

      finish_resolve rs
    end

open_file (path, flags, &block)
Source

    # File lib/rubygems.rb, line 800
    def self.open_file(path, flags, &block)
      File.open(path, flags, &block)
    end

Open a file with given flags

open_file_with_flock (path) { |io| ... }
Source

    # File lib/rubygems.rb, line 818
    def self.open_file_with_flock(path, &block)
      # read-write mode is used rather than read-only in order to support NFS
      mode = IO::RDWR | IO::APPEND | IO::CREAT | IO::BINARY
      mode |= IO::SHARE_DELETE if IO.const_defined?(:SHARE_DELETE)

      File.open(path, mode) do |io|
        begin
          # Try to get a lock without blocking.
          # If we do, the file is locked.
          # Otherwise, explain why we're waiting and get a lock, but block this time.
          if io.flock(File::LOCK_EX | File::LOCK_NB) != 0
            warn "Waiting for another process to let go of lock: #{path}"
            io.flock(File::LOCK_EX)
          end
          io.puts(Process.pid)
        rescue Errno::ENOSYS, Errno::ENOTSUP
        end
        yield io
      end
    end

Open a file with given flags, and protect access with flock

open_file_with_lock (path, &block)
Source

    # File lib/rubygems.rb, line 807
    def self.open_file_with_lock(path, &block)
      file_lock = "#{path}.lock"
      open_file_with_flock(file_lock, &block)
    ensure
      require "fileutils"
      FileUtils.rm_f file_lock
    end

Open a file with given flags, and protect access with a file lock

operating_system_defaults ()
Source

    # File lib/rubygems/defaults.rb, line 286
    def self.operating_system_defaults
      {}
    end

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

path ()
Source

    # File lib/rubygems.rb, line 401
    def self.path
      paths.path
    end

path_separator ()
Source

    # File lib/rubygems/defaults.rb, line 168
    def self.path_separator
      File::PATH_SEPARATOR
    end

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

paths ()
Source

    # File lib/rubygems.rb, line 357
    def self.paths
      @paths ||= Gem::PathSupport.new(ENV)
    end

Retrieve the `PathSupport` object that RubyGems uses to lookup files.

paths= (env)
Source

    # File lib/rubygems.rb, line 367
      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

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`.

platform_defaults ()
Source

    # File lib/rubygems/defaults.rb, line 305
    def self.platform_defaults
      {}
    end

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

platforms ()
Source

    # File lib/rubygems.rb, line 678
    def self.platforms
      @platforms ||= []
      if @platforms.empty?
        @platforms = [Gem::Platform::RUBY, Gem::Platform.local]
      end
      @platforms
    end

`Array` of platforms this RubyGems supports.

platforms= (platforms)
Source

    # File lib/rubygems.rb, line 671
    def self.platforms=(platforms)
      @platforms = platforms
    end

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

plugin_suffix_pattern ()
Source

    # File lib/rubygems.rb, line 964
    def self.plugin_suffix_pattern
      @plugin_suffix_pattern ||= "_plugin#{suffix_pattern}"
    end

Glob pattern for require-able plugin suffixes.

plugin_suffix_regexp ()
Source

    # File lib/rubygems.rb, line 971
    def self.plugin_suffix_regexp
      @plugin_suffix_regexp ||= /_plugin#{suffix_regexp}\z/
    end

`Regexp` for require-able plugin suffixes.

plugindir (install_dir=Gem.dir)
Source

    # File lib/rubygems.rb, line 315
    def self.plugindir(install_dir=Gem.dir)
      File.join install_dir, "plugins"
    end

The path were rubygems plugins are to be installed.

post_build (&hook)
Source

    # File lib/rubygems.rb, line 693
    def self.post_build(&hook)
      @post_build_hooks << hook
    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.

post_install (&hook)
Source

    # File lib/rubygems.rb, line 701
    def self.post_install(&hook)
      @post_install_hooks << hook
    end

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

post_reset (&hook)
Source

    # File lib/rubygems.rb, line 718
    def self.post_reset(&hook)
      @post_reset_hooks << hook
    end

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

post_uninstall (&hook)
Source

    # File lib/rubygems.rb, line 727
    def self.post_uninstall(&hook)
      @post_uninstall_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

pre_install (&hook)
Source

    # File lib/rubygems.rb, line 736
    def self.pre_install(&hook)
      @pre_install_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.

pre_reset (&hook)
Source

    # File lib/rubygems.rb, line 744
    def self.pre_reset(&hook)
      @pre_reset_hooks << hook
    end

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

pre_uninstall (&hook)
Source

    # File lib/rubygems.rb, line 753
    def self.pre_uninstall(&hook)
      @pre_uninstall_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

prefix ()
Source

    # File lib/rubygems.rb, line 762
    def self.prefix
      prefix = File.dirname RUBYGEMS_DIR

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

rdoc_hooks_defined_via_plugin? ()
Source

    # File lib/rubygems/rdoc.rb, line 13
    def self.rdoc_hooks_defined_via_plugin?
      Gem::Version.new(::RDoc::VERSION) >= Gem::Version.new("6.9.0")
    end

Returns whether RDoc defines its own install hooks through a RubyGems plugin. This and whatever is guarded by it can be removed once no supported Ruby ships with RDoc older than 6.9.0.

read_binary (path)
Source

    # File lib/rubygems.rb, line 782
    def self.read_binary(path)
      File.binread(path)
    end

Safely read a file in binary mode on all platforms.

refresh ()
Source

    # File lib/rubygems.rb, line 775
    def self.refresh
      Gem::Specification.reset
    end

Refresh available gems from disk.

register_default_spec (spec)
Source

    # File lib/rubygems.rb, line 1240
    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

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.

ruby ()
Source

    # File lib/rubygems.rb, line 842
    def self.ruby
      if @ruby.nil?
        @ruby = RbConfig.ruby

        @ruby = "\"#{@ruby}\"" if /\s/.match?(@ruby)
      end

      @ruby
    end

The path to the running Ruby interpreter.

ruby_api_version ()
Source

    # File lib/rubygems.rb, line 855
    def self.ruby_api_version
      @ruby_api_version ||= target_rbconfig["ruby_version"].dup
    end

Returns a `String` containing the API compatibility version of Ruby

ruby_engine ()
Source

    # File lib/rubygems/defaults.rb, line 208
    def self.ruby_engine
      RUBY_ENGINE
    end

ruby_version ()
Source

    # File lib/rubygems.rb, line 899
    def self.ruby_version
      return @ruby_version if defined? @ruby_version
      version = RUBY_VERSION.dup

      if RUBY_PATCHLEVEL == -1
        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

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

rubygems_version ()
Source

    # File lib/rubygems.rb, line 918
    def self.rubygems_version
      return @rubygems_version if defined? @rubygems_version
      @rubygems_version = Gem::Version.new Gem::VERSION
    end

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

set_target_rbconfig (rbconfig_path)
Source

    # File lib/rubygems.rb, line 419
    def self.set_target_rbconfig(rbconfig_path)
      @target_rbconfig = Gem::TargetRbConfig.from_path(rbconfig_path)
      Gem::Platform.local(refresh: true)
      Gem.platforms << Gem::Platform.local unless Gem.platforms.include? Gem::Platform.local
      @target_rbconfig
    end

solaris_platform? ()
Source

    # File lib/rubygems.rb, line 1054
    def self.solaris_platform?
      RUBY_PLATFORM.include?("solaris")
    end

Is this platform Solaris?

source_date_epoch ()
Source

    # File lib/rubygems.rb, line 1195
    def self.source_date_epoch
      Time.at(source_date_epoch_string.to_i).utc.freeze
    end

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

This is used throughout RubyGems for enabling reproducible builds.

source_date_epoch_string ()
Source

    # File lib/rubygems.rb, line 1179
    def self.source_date_epoch_string
      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.to_s

      epoch.strip
    end

If the SOURCE_DATE_EPOCH environment variable is set, returns it’s value. Otherwise, returns `DEFAULT_SOURCE_DATE_EPOCH` as a string.

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/

sources ()
Source

    # File lib/rubygems.rb, line 927
    def self.sources
      source_list = configuration.sources || default_sources
      @sources ||= Gem::SourceList.from(source_list)
    end

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

sources= (new_sources)
Source

    # File lib/rubygems.rb, line 939
    def self.sources=(new_sources)
      if !new_sources
        @sources = nil
      else
        @sources = Gem::SourceList.from(new_sources)
      end
    end

Need to be able to set the sources without calling `Gem.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.

spec_cache_dir ()
Source

    # File lib/rubygems.rb, line 405
    def self.spec_cache_dir
      paths.spec_cache_dir
    end

state_file ()
Source

    # File lib/rubygems/defaults.rb, line 140
    def self.state_file
      @state_file ||= File.join(Gem.state_home, "gem", "last_update_check")
    end

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

state_home ()
Source

    # File lib/rubygems/defaults.rb, line 161
    def self.state_home
      @state_home ||= ENV["XDG_STATE_HOME"] || File.join(Gem.user_home, ".local", "state")
    end

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

suffix_pattern ()
Source

    # File lib/rubygems.rb, line 950
    def self.suffix_pattern
      @suffix_pattern ||= "{#{suffixes.join(",")}}"
    end

Glob pattern for require-able path suffixes.

suffix_regexp ()
Source

    # File lib/rubygems.rb, line 957
    def self.suffix_regexp
      @suffix_regexp ||= /#{Regexp.union(suffixes)}\z/
    end

`Regexp` for require-able path suffixes.

suffixes ()
Source

    # File lib/rubygems.rb, line 978
    def self.suffixes
      @suffixes ||= ["",
                     ".rb",
                     *%w[DLEXT DLEXT2].map do |key|
                       val = RbConfig::CONFIG[key]
                       next unless val && !val.empty?
                       ".#{val}"
                     end].compact.uniq
    end

Suffixes for require-able paths.

target_rbconfig ()
Source

    # File lib/rubygems.rb, line 415
    def self.target_rbconfig
      @target_rbconfig || Gem::TargetRbConfig.for_running_ruby
    end

The `RbConfig` object for the deployment target platform.

This is usually the same as the running platform, but may be different if you are cross-compiling.

time (msg, width = 0, display = Gem.configuration.verbose) { || ... }
Source

    # File lib/rubygems.rb, line 999
    def self.time(msg, width = 0, display = Gem.configuration.verbose)
      now = Time.now

      value = yield

      elapsed = Time.now - now

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

      value
    end

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

try_activate (path)
Source

    # File lib/rubygems.rb, line 197
    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

      true
    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.

ui ()
Source

    # File lib/rubygems.rb, line 1014
    def self.ui
      require_relative "rubygems/user_interaction"

      Gem::DefaultUserInteraction.ui
    end

Lazily loads `DefaultUserInteraction` and returns the default UI.

use_gemdeps (path = nil)
Source

    # File lib/rubygems.rb, line 1120
    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

      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
          Bundler.ui.silence do
            @gemdeps = Bundler.setup
          end
        ensure
          Gem::DefaultUserInteraction.ui.close
        end
      rescue Bundler::BundlerError => e
        warn e.message
        warn "You may need to `bundle install` to install missing gems"
        warn ""
      end
    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.

use_paths (home, *paths)
Source

    # File lib/rubygems.rb, line 1024
    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

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

user_dir ()
Source

    # File lib/rubygems/defaults.rb, line 103
    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

Path for gems in the user’s home directory

user_home ()
Source

    # File lib/rubygems/defaults.rb, line 96
    def self.user_home
      @user_home ||= find_home
    end

The home directory for the user.

win_platform? ()
Source

    # File lib/rubygems.rb, line 1035
    def self.win_platform?
      if @@win_platform.nil?
        ruby_platform = RbConfig::CONFIG["host_os"]
        @@win_platform = !WIN_PATTERNS.find {|r| ruby_platform =~ r }.nil?
      end

      @@win_platform
    end

Is this a windows platform?

write_binary (path, data)
Source

    # File lib/rubygems.rb, line 789
    def self.write_binary(path, data)
      File.binwrite(path, data)
    rescue Errno::ENOSPC
      # If we ran out of space but the file exists, it's *guaranteed* to be corrupted.
      File.delete(path) if File.exist?(path)
      raise
    end

Safely write a file in binary mode on all platforms.

### Private Class Methods

already_loaded? (file)
Source

    # File lib/rubygems.rb, line 1331
    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

default_gem_load_paths ()
Source

    # File lib/rubygems.rb, line 1337
    def default_gem_load_paths
      @default_gem_load_paths ||= $LOAD_PATH[load_path_insert_index..-1].map do |lp|
        expanded = File.expand_path(lp)
        next expanded unless File.exist?(expanded)

        File.realpath(expanded)
      end
    end

find_home ()
Source

    # File lib/rubygems/defaults.rb, line 81
    def self.find_home
      Dir.home.dup
    rescue StandardError
      if Gem.win_platform?
        File.expand_path File.join(ENV["HOMEDRIVE"] || ENV["SystemDrive"], "/")
      else
        File.expand_path "/"
      end
    end

Finds the user’s home directory.

find_spec_for_exe (name, exec_name, requirements)
Source

    # File lib/rubygems.rb, line 252
    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}"
        raise Gem::GemNotFoundException, msg
      end

      spec
    end