Class: Gem::Installer

Inherits:
Object
  • Object
show all
Includes:
UserInteraction
Defined in:
lib/rubygems/installer.rb,
lib/rubygems/installer_test_case.rb

Overview

The installer installs the files contained in the .gem into the Gem.home.

Gem::Installer does the work of putting files in all the right places on the filesystem including unpacking the gem into its gem dir, installing the gemspec in the specifications dir, storing the cached gem in the cache dir, and installing either wrappers or symlinks for executables.

The installer invokes pre and post install hooks. Hooks can be added either through a rubygems_plugin.rb file in an installed gem or via a rubygems/defaults/#RUBY_ENGINE.rb or rubygems/defaults/operating_system.rb file. See Gem.pre_install and Gem.post_install for details.

Constant Summary collapse

ENV_PATHS =

Paths where env(1) might live. Some systems are broken and have it in /bin

%w[/usr/bin/env /bin/env]
ExtensionBuildError =

Deprecated in favor of Gem::Ext::BuildError

Gem::Ext::BuildError

Class Attribute Summary collapse

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from UserInteraction

#alert, #alert_error, #alert_warning, #ask, #ask_for_password, #ask_yes_no, #choose_from_list, #say, #terminate_interaction

Methods included from DefaultUserInteraction

ui, #ui, ui=, #ui=, use_ui, #use_ui

Constructor Details

#initialize(gem, options = {}) ⇒ Installer

Constructs an Installer instance that will install the gem located at gem. options is a Hash with the following keys:

:bin_dir

Where to put a bin wrapper if needed.

:development

Whether or not development dependencies should be installed.

:env_shebang

Use /usr/bin/env in bin wrappers.

:force

Overrides all version checks and security policy checks, except for a signed-gems-only policy.

:format_executable

Format the executable the same as the Ruby executable. If your Ruby is ruby18, foo_exec will be installed as foo_exec18.

:ignore_dependencies

Don’t raise if a dependency is missing.

:install_dir

The directory to install the gem into.

:security_policy

Use the specified security policy. See Gem::Security

:user_install

Indicate that the gem should be unpacked into the users personal gem directory.

:only_install_dir

Only validate dependencies against what is in the install_dir

:wrappers

Install wrappers if true, symlinks if false.

:build_args

An Array of arguments to pass to the extension builder process. If not set, then Gem::Command.build_args is used



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# File 'lib/rubygems/installer.rb', line 107

def initialize(gem, options={})
  require 'fileutils'

  @gem = gem
  @options = options
  @package = Gem::Package.new @gem

  process_options

  @package.security_policy = @security_policy

  if options[:user_install] and not options[:unpack] then
    @gem_home = Gem.user_dir
    @bin_dir = Gem.bindir gem_home unless options[:bin_dir]
    check_that_user_bin_dir_is_in_path
  end
end

Class Attribute Details

.exec_format ⇒ Object

Defaults to use Ruby’s program prefix and suffix.



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# File 'lib/rubygems/installer.rb', line 78

def exec_format
  @exec_format ||= Gem.default_exec_format
end

.path_warning ⇒ Object

True if we’ve warned about PATH not including Gem.bindir



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# File 'lib/rubygems/installer.rb', line 72

def path_warning
  @path_warning
end

Instance Attribute Details

#bin_dir ⇒ Object

The directory a gem’s executables will be installed into



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# File 'lib/rubygems/installer.rb', line 48

def bin_dir
  @bin_dir
end

#build_args=(value) ⇒ Object (writeonly)

Available through requiring rubygems/installer_test_case



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

def build_args=(value)
  @build_args = value
end

#env_shebang=(value) ⇒ Object (writeonly)

Available through requiring rubygems/installer_test_case



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# File 'lib/rubygems/installer_test_case.rb', line 39

def env_shebang=(value)
  @env_shebang = value
end

#force=(value) ⇒ Object (writeonly)

Available through requiring rubygems/installer_test_case



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# File 'lib/rubygems/installer_test_case.rb', line 24

def force=(value)
  @force = value
end

#format=(value) ⇒ Object (writeonly)

Available through requiring rubygems/installer_test_case



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# File 'lib/rubygems/installer_test_case.rb', line 29

def format=(value)
  @format = value
end

#format_executable=(value) ⇒ Object (writeonly)

Available through requiring rubygems/installer_test_case



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# File 'lib/rubygems/installer_test_case.rb', line 49

def format_executable=(value)
  @format_executable = value
end

#gem ⇒ Object (readonly)

DOC: Missing docs or :nodoc:.



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# File 'lib/rubygems/installer.rb', line 43

def gem
  @gem
end

#gem_dir ⇒ Object

Lazy accessor for the spec’s gem directory.



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# File 'lib/rubygems/installer.rb', line 188

def gem_dir
  @gem_dir ||= File.join(gem_home, "gems", spec.full_name)
end

#gem_home ⇒ Object

The gem repository the gem will be installed into



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# File 'lib/rubygems/installer.rb', line 53

def gem_home
  @gem_home
end

#ignore_dependencies=(value) ⇒ Object (writeonly)

Available through requiring rubygems/installer_test_case



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# File 'lib/rubygems/installer_test_case.rb', line 44

def ignore_dependencies=(value)
  @ignore_dependencies = value
end

#options ⇒ Object (readonly)

The options passed when the Gem::Installer was instantiated.



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# File 'lib/rubygems/installer.rb', line 58

def options
  @options
end

#security_policy=(value) ⇒ Object (writeonly)

Available through requiring rubygems/installer_test_case



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# File 'lib/rubygems/installer_test_case.rb', line 54

def security_policy=(value)
  @security_policy = value
end

#spec ⇒ Object

Lazy accessor for the installer’s spec.



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# File 'lib/rubygems/installer.rb', line 195

def spec
  @spec ||= @package.spec
rescue Gem::Package::Error => e
  raise Gem::InstallError, "invalid gem: #{e.message}"
end

#wrappers=(value) ⇒ Object (writeonly)

Available through requiring rubygems/installer_test_case



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# File 'lib/rubygems/installer_test_case.rb', line 59

def wrappers=(value)
  @wrappers = value
end

Instance Method Details

#app_script_text(bin_file_name) ⇒ Object

Return the text for an application file.



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# File 'lib/rubygems/installer.rb', line 627

def app_script_text(bin_file_name)
  return <<-TEXT
#{shebang bin_file_name}
#
# This file was generated by RubyGems.
#
# The application '#{spec.name}' is installed as part of a gem, and
# this file is here to facilitate running it.
#

require 'rubygems'

version = "#{Gem::Requirement.default}"

if ARGV.first
str = ARGV.first
str = str.dup.force_encoding("BINARY") if str.respond_to? :force_encoding
if str =~ /\\A_(.*)_\\z/
  version = $1
  ARGV.shift
end
end

gem '#{spec.name}', version
load Gem.bin_path('#{spec.name}', '#{bin_file_name}', version)
TEXT
end

#build_extensions ⇒ Object

Builds extensions. Valid types of extensions are extconf.rb files, configure scripts and rakefiles or mkrf_conf files.



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# File 'lib/rubygems/installer.rb', line 674

def build_extensions
  builder = Gem::Ext::Builder.new spec, @build_args

  builder.build_extensions
end

#check_executable_overwrite(filename) ⇒ Object

Checks if filename exists in @bin_dir.

If @force is set filename is overwritten.

If filename exists and is a RubyGems wrapper for different gem the user is consulted.

If filename exists and @bin_dir is Gem.default_bindir (/usr/local) the user is consulted.

Otherwise filename is overwritten.

Raises:



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# File 'lib/rubygems/installer.rb', line 138

def check_executable_overwrite filename # :nodoc:
  return if @force

  generated_bin = File.join @bin_dir, formatted_program_filename(filename)

  return unless File.exist? generated_bin

  ruby_executable = false
  existing = nil

  open generated_bin, 'rb' do |io|
    next unless io.gets =~ /^#!/ # shebang
    io.gets # blankline

    # TODO detect a specially formatted comment instead of trying
    # to run a regexp against Ruby code.
    next unless io.gets =~ /This file was generated by RubyGems/

    ruby_executable = true
    existing = io.read.slice(/^gem (['"])(.*?)(\1),/, 2)
  end

  return if spec.name == existing

  # somebody has written to RubyGems' directory, overwrite, too bad
  return if Gem.default_bindir != @bin_dir and not ruby_executable

  question = "#{spec.name}'s executable \"#{filename}\" conflicts with "

  if ruby_executable then
    question << existing

    return if ask_yes_no "#{question}\nOverwrite the executable?", false

    conflict = "installed executable from #{existing}"
  else
    question << generated_bin

    return if ask_yes_no "#{question}\nOverwrite the executable?", false

    conflict = generated_bin
  end

  raise Gem::InstallError,
    "\"#{filename}\" from #{spec.name} conflicts with #{conflict}"
end

#check_that_user_bin_dir_is_in_path ⇒ Object

DOC: Missing docs or :nodoc:.



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# File 'lib/rubygems/installer.rb', line 598

def check_that_user_bin_dir_is_in_path
  user_bin_dir = @bin_dir || Gem.bindir(gem_home)
  user_bin_dir = user_bin_dir.gsub(File::SEPARATOR, File::ALT_SEPARATOR) if
    File::ALT_SEPARATOR

  path = ENV['PATH']
  if Gem.win_platform? then
    path = path.downcase
    user_bin_dir = user_bin_dir.downcase
  end

  unless path.split(File::PATH_SEPARATOR).include? user_bin_dir then
    unless self.class.path_warning then
      alert_warning "You don't have #{user_bin_dir} in your PATH,\n\t  gem executables will not run."
      self.class.path_warning = true
    end
  end
end

#default_spec_file ⇒ Object

The location of of the default spec file for default gems.



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# File 'lib/rubygems/installer.rb', line 346

def default_spec_file
  File.join gem_home, "specifications/default", "#{spec.full_name}.gemspec"
end

#dir ⇒ Object

Return the target directory where the gem is to be installed. This directory is not guaranteed to be populated.



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

def dir
  gem_dir.to_s
end

#ensure_dependencies_met ⇒ Object

DOC: Missing docs or :nodoc:.



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# File 'lib/rubygems/installer.rb', line 560

def ensure_dependencies_met
  deps = spec.runtime_dependencies
  deps |= spec.development_dependencies if @development

  deps.each do |dep_gem|
    ensure_dependency spec, dep_gem
  end
end

#ensure_dependency(spec, dependency) ⇒ Object

Ensure that the dependency is satisfied by the current installation of gem. If it is not an exception is raised.

spec

Gem::Specification

dependency

Gem::Dependency



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# File 'lib/rubygems/installer.rb', line 310

def ensure_dependency(spec, dependency)
  unless installation_satisfies_dependency? dependency then
    raise Gem::InstallError, "#{spec.name} requires #{dependency}"
  end
  true
end

#ensure_loadable_spec ⇒ Object

Ensures the Gem::Specification written out for this gem is loadable upon installation.



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# File 'lib/rubygems/installer.rb', line 527

def ensure_loadable_spec
  ruby = spec.to_ruby_for_cache
  ruby.untaint

  begin
    eval ruby
  rescue StandardError, SyntaxError => e
    raise Gem::InstallError,
          "The specification for #{spec.full_name} is corrupt (#{e.class})"
  end
end

#ensure_required_ruby_version_met ⇒ Object

DOC: Missing docs or :nodoc:.



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# File 'lib/rubygems/installer.rb', line 540

def ensure_required_ruby_version_met
  if rrv = spec.required_ruby_version then
    unless rrv.satisfied_by? Gem.ruby_version then
      raise Gem::InstallError, "#{spec.name} requires Ruby version #{rrv}."
    end
  end
end

#ensure_required_rubygems_version_met ⇒ Object

DOC: Missing docs or :nodoc:.



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# File 'lib/rubygems/installer.rb', line 549

def ensure_required_rubygems_version_met
  if rrgv = spec.required_rubygems_version then
    unless rrgv.satisfied_by? Gem.rubygems_version then
      raise Gem::InstallError,
        "#{spec.name} requires RubyGems version #{rrgv}. " +
        "Try 'gem update --system' to update RubyGems itself."
    end
  end
end

#extension_build_error(build_dir, output, backtrace = nil) ⇒ Object

Logs the build output in build_dir, then raises Gem::Ext::BuildError.

TODO: Delete this for RubyGems 3. It remains for API compatibility



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# File 'lib/rubygems/installer.rb', line 685

def extension_build_error(build_dir, output, backtrace = nil) # :nodoc:
  builder = Gem::Ext::Builder.new spec, @build_args

  builder.build_error build_dir, output, backtrace
end

#extract_bin ⇒ Object

Extracts only the bin/ files from the gem into the gem directory. This is used by default gems to allow a gem-aware stub to function without the full gem installed.



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# File 'lib/rubygems/installer.rb', line 705

def extract_bin
  @package.extract_files gem_dir, "bin/*"
end

#extract_files ⇒ Object

Reads the file index and extracts each file into the gem directory.

Ensures that files can’t be installed outside the gem directory.



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# File 'lib/rubygems/installer.rb', line 696

def extract_files
  @package.extract_files gem_dir
end

#formatted_program_filename(filename) ⇒ Object

Prefix and suffix the program filename the same as ruby.



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# File 'lib/rubygems/installer.rb', line 712

def formatted_program_filename(filename)
  if @format_executable then
    self.class.exec_format % File.basename(filename)
  else
    filename
  end
end

#generate_bin ⇒ Object

DOC: Missing docs or :nodoc:.

Raises:



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# File 'lib/rubygems/installer.rb', line 390

def generate_bin
  return if spec.executables.nil? or spec.executables.empty?

  Dir.mkdir @bin_dir unless File.exist? @bin_dir
  raise Gem::FilePermissionError.new(@bin_dir) unless File.writable? @bin_dir

  spec.executables.each do |filename|
    filename.untaint
    bin_path = File.join gem_dir, spec.bindir, filename

    unless File.exist? bin_path then
      # TODO change this to a more useful warning
      warn "#{bin_path} maybe `gem pristine #{spec.name}` will fix it?"
      next
    end

    mode = File.stat(bin_path).mode | 0111
    FileUtils.chmod mode, bin_path

    check_executable_overwrite filename

    if @wrappers then
      generate_bin_script filename, @bin_dir
    else
      generate_bin_symlink filename, @bin_dir
    end

  end
end

#generate_bin_script(filename, bindir) ⇒ Object

Creates the scripts to run the applications in the gem. – The Windows script is generated in addition to the regular one due to a bug or misfeature in the Windows shell’s pipe. See blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-talk/193379



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# File 'lib/rubygems/installer.rb', line 427

def generate_bin_script(filename, bindir)
  bin_script_path = File.join bindir, formatted_program_filename(filename)

  FileUtils.rm_f bin_script_path # prior install may have been --no-wrappers

  File.open bin_script_path, 'wb', 0755 do |file|
    file.print app_script_text(filename)
  end

  say bin_script_path if Gem.configuration.really_verbose

  generate_windows_script filename, bindir
end

#generate_bin_symlink(filename, bindir) ⇒ Object

Creates the symlinks to run the applications in the gem. Moves the symlink if the gem being installed has a newer version.



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# File 'lib/rubygems/installer.rb', line 445

def generate_bin_symlink(filename, bindir)
  if Gem.win_platform? then
    alert_warning "Unable to use symlinks on Windows, installing wrapper"
    generate_bin_script filename, bindir
    return
  end

  src = File.join gem_dir, spec.bindir, filename
  dst = File.join bindir, formatted_program_filename(filename)

  if File.exist? dst then
    if File.symlink? dst then
      link = File.readlink(dst).split File::SEPARATOR
      cur_version = Gem::Version.create(link[-3].sub(/^.*-/, ''))
      return if spec.version < cur_version
    end
    File.unlink dst
  end

  FileUtils.symlink src, dst, :verbose => Gem.configuration.really_verbose
end

#generate_windows_script(filename, bindir) ⇒ Object

Creates windows .bat files for easy running of commands



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# File 'lib/rubygems/installer.rb', line 377

def generate_windows_script(filename, bindir)
  if Gem.win_platform? then
    script_name = filename + ".bat"
    script_path = File.join bindir, File.basename(script_name)
    File.open script_path, 'w' do |file|
      file.puts windows_stub_script(bindir, filename)
    end

    say script_path if Gem.configuration.really_verbose
  end
end

#install ⇒ Object

Installs the gem and returns a loaded Gem::Specification for the installed gem.

The gem will be installed with the following structure:

@gem_home/
  cache/<gem-version>.gem #=> a cached copy of the installed gem
  gems/<gem-version>/... #=> extracted files
  specifications/<gem-version>.gemspec #=> the Gem::Specification



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# File 'lib/rubygems/installer.rb', line 212

def install
  pre_install_checks

  FileUtils.rm_f File.join gem_home, 'specifications', @spec.spec_name

  run_pre_install_hooks

  # Completely remove any previous gem files
  FileUtils.rm_rf gem_dir

  FileUtils.mkdir_p gem_dir

  spec.loaded_from = spec_file

  if @options[:install_as_default]
    extract_bin
    write_default_spec
  else
    extract_files

    build_extensions
    write_build_info_file
    run_post_build_hooks

    generate_bin
    write_spec
    write_cache_file
  end

  say spec.post_install_message unless spec.post_install_message.nil?

  Gem::Specification.add_spec spec unless Gem::Specification.include? spec

  run_post_install_hooks

  spec

# TODO This rescue is in the wrong place. What is raising this exception?
# move this rescue to around the code that actually might raise it.
rescue Zlib::GzipFile::Error
  raise Gem::InstallError, "gzip error installing #{gem}"
end

#installation_satisfies_dependency?(dependency) ⇒ Boolean

True if the gems in the system satisfy dependency.

Returns:

  • (Boolean) 


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# File 'lib/rubygems/installer.rb', line 320

def installation_satisfies_dependency?(dependency)
  return true if installed_specs.detect { |s| dependency.matches_spec? s }
  return false if @only_install_dir
  not dependency.matching_specs.empty?
end

#installed_specs ⇒ Object

Return an Array of Specifications contained within the gem_home we’ll be installing into.



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# File 'lib/rubygems/installer.rb', line 290

def installed_specs
  @specs ||= begin
    specs = []

    Dir[File.join(gem_home, "specifications", "*.gemspec")].each do |path|
      spec = Gem::Specification.load path.untaint
      specs << spec if spec
    end

    specs
  end
end

#pre_install_checks ⇒ Object

Performs various checks before installing the gem such as the install repository is writable and its directories exist, required Ruby and rubygems versions are met and that dependencies are installed.

Version and dependency checks are skipped if this install is forced.

The dependent check will be skipped this install is ignoring dependencies.



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# File 'lib/rubygems/installer.rb', line 739

def pre_install_checks
  verify_gem_home options[:unpack]

  # If we're forcing the install then disable security unless the security
  # policy says that we only install signed gems.
  @security_policy = nil if
    @force and @security_policy and not @security_policy.only_signed

  ensure_loadable_spec

  if options[:install_as_default]
    Gem.ensure_default_gem_subdirectories gem_home
  else
    Gem.ensure_gem_subdirectories gem_home
  end

  return true if @force

  ensure_required_ruby_version_met
  ensure_required_rubygems_version_met
  ensure_dependencies_met unless @ignore_dependencies

  true
end

#process_options ⇒ Object

DOC: Missing docs or :nodoc:.



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# File 'lib/rubygems/installer.rb', line 570

def process_options
  @options = {
    :bin_dir      => nil,
    :env_shebang  => false,
    :force        => false,
    :only_install_dir => false
  }.merge options

  @env_shebang         = options[:env_shebang]
  @force               = options[:force]
  @install_dir         = options[:install_dir]
  @gem_home            = options[:install_dir] || Gem.dir
  @ignore_dependencies = options[:ignore_dependencies]
  @format_executable   = options[:format_executable]
  @security_policy     = options[:security_policy]
  @wrappers            = options[:wrappers]
  @only_install_dir    = options[:only_install_dir]

  # If the user has asked for the gem to be installed in a directory that is
  # the system gem directory, then use the system bin directory, else create
  # (or use) a new bin dir under the gem_home.
  @bin_dir             = options[:bin_dir] || Gem.bindir(gem_home)
  @development         = options[:development]

  @build_args          = options[:build_args] || Gem::Command.build_args
end

#run_post_build_hooks ⇒ Object

:nodoc:



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# File 'lib/rubygems/installer.rb', line 266

def run_post_build_hooks # :nodoc:
  Gem.post_build_hooks.each do |hook|
    if hook.call(self) == false then
      FileUtils.rm_rf gem_dir

      location = " at #{$1}" if hook.inspect =~ /@(.*:\d+)/

      message = "post-build hook#{location} failed for #{spec.full_name}"
      raise Gem::InstallError, message
    end
  end
end

#run_post_install_hooks ⇒ Object

:nodoc:



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# File 'lib/rubygems/installer.rb', line 279

def run_post_install_hooks # :nodoc:
  Gem.post_install_hooks.each do |hook|
    hook.call self
  end
end

#run_pre_install_hooks ⇒ Object

:nodoc:



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# File 'lib/rubygems/installer.rb', line 255

def run_pre_install_hooks # :nodoc:
  Gem.pre_install_hooks.each do |hook|
    if hook.call(self) == false then
      location = " at #{$1}" if hook.inspect =~ /@(.*:\d+)/

      message = "pre-install hook#{location} failed for #{spec.full_name}"
      raise Gem::InstallError, message
    end
  end
end

#shebang(bin_file_name) ⇒ Object

Generates a #! line for bin_file_name‘s wrapper copying arguments if necessary.

If the :custom_shebang config is set, then it is used as a template for how to create the shebang used for to run a gem’s executables.

The template supports 4 expansions:

$env    the path to the unix env utility
$ruby   the path to the currently running ruby interpreter
$exec   the path to the gem's executable
$name   the name of the gem the executable is for



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# File 'lib/rubygems/installer.rb', line 482

def shebang(bin_file_name)
  ruby_name = Gem::ConfigMap[:ruby_install_name] if @env_shebang
  path = File.join gem_dir, spec.bindir, bin_file_name
  first_line = File.open(path, "rb") {|file| file.gets}

  if /\A#!/ =~ first_line then
    # Preserve extra words on shebang line, like "-w".  Thanks RPA.
    shebang = first_line.sub(/\A\#!.*?ruby\S*((\s+\S+)+)/, "#!#{Gem.ruby}")
    opts = $1
    shebang.strip! # Avoid nasty ^M issues.
  end

  if which = Gem.configuration[:custom_shebang]
    # replace bin_file_name with "ruby" to avoid endless loops
    which = which.gsub(/ #{bin_file_name}$/," #{Gem::ConfigMap[:ruby_install_name]}")

    which = which.gsub(/\$(\w+)/) do
      case $1
      when "env"
        @env_path ||= ENV_PATHS.find {|env_path| File.executable? env_path }
      when "ruby"
        "#{Gem.ruby}#{opts}"
      when "exec"
        bin_file_name
      when "name"
        spec.name
      end
    end

    "#!#{which}"
  elsif not ruby_name then
    "#!#{Gem.ruby}#{opts}"
  elsif opts then
    "#!/bin/sh\n'exec' #{ruby_name.dump} '-x' \"$0\" \"$@\"\n#{shebang}"
  else
    # Create a plain shebang line.
    @env_path ||= ENV_PATHS.find {|env_path| File.executable? env_path }
    "#!#{@env_path} #{ruby_name}"
  end
end

#spec_file ⇒ Object

The location of of the spec file that is installed.



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# File 'lib/rubygems/installer.rb', line 338

def spec_file
  File.join gem_home, "specifications", "#{spec.full_name}.gemspec"
end

#unpack(directory) ⇒ Object

Unpacks the gem into the given directory.



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# File 'lib/rubygems/installer.rb', line 329

def unpack(directory)
  @gem_dir = directory
  extract_files
end

#verify_gem_home(unpack = false) ⇒ Object

DOC: Missing docs or :nodoc:.

Raises:



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# File 'lib/rubygems/installer.rb', line 618

def verify_gem_home(unpack = false)
  FileUtils.mkdir_p gem_home
  raise Gem::FilePermissionError, gem_home unless
    unpack or File.writable?(gem_home)
end

#windows_stub_script(bindir, bin_file_name) ⇒ Object

return the stub script text used to launch the true Ruby script



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# File 'lib/rubygems/installer.rb', line 658

def windows_stub_script(bindir, bin_file_name)
  ruby = File.basename(Gem.ruby).chomp('"')
  return <<-TEXT
@ECHO OFF
IF NOT "%~f0" == "~f0" GOTO :WinNT
@"#{ruby}" "#{File.join(bindir, bin_file_name)}" %1 %2 %3 %4 %5 %6 %7 %8 %9
GOTO :EOF
:WinNT
@"#{ruby}" "%~dpn0" %*
TEXT
end

#write_build_info_file ⇒ Object

Writes the file containing the arguments for building this gem’s extensions.



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# File 'lib/rubygems/installer.rb', line 768

def write_build_info_file
  return if @build_args.empty?

  build_info_dir = File.join gem_home, 'build_info'

  FileUtils.mkdir_p build_info_dir

  build_info_file = File.join build_info_dir, "#{spec.full_name}.info"

  open build_info_file, 'w' do |io|
    @build_args.each do |arg|
      io.puts arg
    end
  end
end

#write_cache_file ⇒ Object

Writes the .gem file to the cache directory



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# File 'lib/rubygems/installer.rb', line 787

def write_cache_file
  cache_file = File.join gem_home, 'cache', spec.file_name

  FileUtils.cp @gem, cache_file unless File.exist? cache_file
end

#write_default_spec ⇒ Object

Writes the full .gemspec specification (in Ruby) to the gem home’s specifications/default directory.



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

def write_default_spec
  File.open(default_spec_file, "w") do |file|
    file.puts spec.to_ruby
  end
end

#write_spec ⇒ Object

Writes the .gemspec specification (in Ruby) to the gem home’s specifications directory.



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# File 'lib/rubygems/installer.rb', line 354

def write_spec
  open spec_file, 'w' do |file|
    spec.installed_by_version = Gem.rubygems_version

    file.puts spec.to_ruby_for_cache

    file.fsync rescue nil # for filesystems without fsync(2)
  end
end