brew/Library/Homebrew/cmd/--env.rb

require 'extend/ENV'
require 'hardware'

module Homebrew extend self
  def __env
    ENV.extend(HomebrewEnvExtension)
    ENV.setup_build_environment
    ENV.universal_binary if ARGV.build_universal?
    if $stdout.tty?
      dump_build_env ENV
    else
      build_env_keys(ENV).each do |key|
        puts "export #{key}=\"#{ENV[key]}\""
      end
    end
  end

  def build_env_keys env
    %w[ CC CXX LD CFLAGS CXXFLAGS CPPFLAGS CMAKE_PREFIX_PATH
      CMAKE_INBLUDE_PATH LDFLAGS MACOSX_DEPLOYMENT_TARGET MAKEFLAGS
      PKG_CONFIG_PATH HOMEBREW_BUILD_FROM_SOURCE HOMEBREW_DEBUG
      HOMEBREW_MAKE_JOBS HOMEBREW_VERBOSE HOMEBREW_USE_CLANG HOMEBREW_USE_GCC
      HOMEBREW_USE_LLVM HOMEBREW_SVN ].select{ |key| env[key] }
  end

  def dump_build_env env
    build_env_keys(env).each do |key|
      value = env[key]
      print "#{key}: #{value}"
      case key when 'CC', 'CXX', 'LD'
        if value =~ %r{/usr/bin/xcrun (.*)}
          path = `/usr/bin/xcrun -find #{$1}`
          print " => #{path}"
        elsif File.symlink? value
          print " => #{Pathname.new(value).realpath}"
        end
      end
      puts
    end
  end
end