brew/Library/Homebrew/utils/gems.rb

# frozen_string_literal: true

# Never `require` anything in this file (except English). It needs to be able to
# work as the first item in `brew.rb` so we can load gems with Bundler when
# needed before anything else is loaded (e.g. `json`).

require "English"

module Homebrew
  # Keep in sync with the Gemfile.lock's BUNDLED WITH.
  HOMEBREW_BUNDLER_VERSION = "1.17.2"

  module_function

  def ruby_bindir
    "#{RbConfig::CONFIG["prefix"]}/bin"
  end

  def gem_user_bindir
    require "rubygems"
    "#{Gem.user_dir}/bin"
  end

  def ohai_if_defined(message)
    if defined?(ohai)
      ohai message
    else
      puts "==> #{message}"
    end
  end

  def odie_if_defined(message)
    if defined?(odie)
      odie message
    else
      $stderr.puts "Error: #{message}"
      exit 1
    end
  end

  def setup_gem_environment!(gem_home: nil, gem_bindir: nil)
    require "rubygems"

    # Match where our bundler gems are.
    gem_home ||= "#{ENV["HOMEBREW_LIBRARY"]}/Homebrew/vendor/bundle/ruby/#{RbConfig::CONFIG["ruby_version"]}"
    ENV["GEM_HOME"] = gem_home
    ENV["GEM_PATH"] = "#{ENV["GEM_HOME"]}:#{Gem.default_dir}"

    # Set TMPDIR so Xcode's `make` doesn't fall back to `/var/tmp/`,
    # which may be not user-writable.
    ENV["TMPDIR"] = ENV["HOMEBREW_TEMP"]

    # Make RubyGems notice environment changes.
    Gem.clear_paths
    Gem::Specification.reset

    # Add necessary Ruby and Gem binary directories to PATH.
    gem_bindir ||= Gem.bindir
    paths = ENV["PATH"].split(":")
    paths.unshift(gem_bindir) unless paths.include?(gem_bindir)
    paths.unshift(ruby_bindir) unless paths.include?(ruby_bindir)
    ENV["PATH"] = paths.compact.join(":")
  end

  def install_gem!(name, version: nil, setup_gem_environment: true)
    setup_gem_environment! if setup_gem_environment
    return unless Gem::Specification.find_all_by_name(name, version).empty?

    # Shell out to `gem` to avoid RubyGems requires for e.g. loading JSON.
    ohai_if_defined "Installing '#{name}' gem"
    install_args = %W[--no-document #{name}]
    install_args << "--version" << version if version
    return if system "#{ruby_bindir}/gem", "install", *install_args

    odie_if_defined "failed to install the '#{name}' gem."
  end

  def install_gem_setup_path!(name, version: nil, executable: name, setup_gem_environment: true)
    install_gem!(name, version: version, setup_gem_environment: setup_gem_environment)
    return if find_in_path(executable)

    odie_if_defined <<~EOS
      the '#{name}' gem is installed but couldn't find '#{executable}' in the PATH:
        #{ENV["PATH"]}
    EOS
  end

  def find_in_path(executable)
    ENV["PATH"].split(":").find do |path|
      File.executable?("#{path}/#{executable}")
    end
  end

  def install_bundler!
    require "rubygems"
    setup_gem_environment!(gem_home: Gem.user_dir, gem_bindir: gem_user_bindir)
    install_gem_setup_path!(
      "bundler",
      version:               HOMEBREW_BUNDLER_VERSION,
      executable:            "bundle",
      setup_gem_environment: false,
    )
  end

  def install_bundler_gems!
    install_bundler!

    ENV["BUNDLE_GEMFILE"] = "#{ENV["HOMEBREW_LIBRARY"]}/Homebrew/Gemfile"
    @bundle_installed ||= begin
      bundle = "#{find_in_path(:bundle)}/bundle"
      bundle_check_output = `#{bundle} check 2>&1`
      bundle_check_failed = !$CHILD_STATUS.success?

      # for some reason sometimes the exit code lies so check the output too.
      if bundle_check_failed || bundle_check_output.include?("Install missing gems")
        unless system bundle, "install"
          odie_if_defined <<~EOS
            failed to run `#{bundle} install`!
          EOS
        end
      else
        true
      end
    end

    setup_gem_environment!
  end
end