module Bundler::SharedHelpers

def chdir(dir, &blk)
  Bundler.rubygems.ext_lock.synchronize do
    Dir.chdir dir, &blk
  end
end

def clean_load_path
  # handle 1.9 where system gems are always on the load path
  if defined?(::Gem)
    me = File.expand_path("../../", __FILE__)
    me = /^#{Regexp.escape(me)}/
    loaded_gem_paths = Bundler.rubygems.loaded_gem_paths
    $LOAD_PATH.reject! do |p|
      next if File.expand_path(p) =~ me
      loaded_gem_paths.delete(p)
    end
    $LOAD_PATH.uniq!
  end
end

def const_get_safely(constant_name, namespace)
  const_in_namespace = namespace.constants.include?(constant_name.to_s) ||
    namespace.constants.include?(constant_name.to_sym)
  return nil unless const_in_namespace
  namespace.const_get(constant_name)
end

def default_bundle_dir
  bundle_dir = find_directory(".bundle")
  return nil unless bundle_dir
  global_bundle_dir = File.join(Bundler.rubygems.user_home, ".bundle")
  return nil if bundle_dir == global_bundle_dir
  Pathname.new(bundle_dir)
end

def default_gemfile
  gemfile = find_gemfile
  raise GemfileNotFound, "Could not locate Gemfile" unless gemfile
  Pathname.new(gemfile)
end

def default_lockfile
  gemfile = default_gemfile
  case gemfile.basename.to_s
  when "gems.rb" then Pathname.new(gemfile.sub(/.rb$/, ".locked"))
  else Pathname.new("#{gemfile}.lock")
  end
end

def filesystem_access(path, action = :write)
  yield path
rescue Errno::EACCES
  raise PermissionError.new(path, action)
rescue Errno::EAGAIN
  raise TemporaryResourceError.new(path, action)
rescue Errno::EPROTO
  raise VirtualProtocolError.new
end

def find_directory(*names)
  search_up(*names) do |dirname|
    return dirname if File.directory?(dirname)
  end
end

def find_file(*names)
  search_up(*names) do |filename|
    return filename if File.file?(filename)
  end
end

def find_gemfile
  given = ENV["BUNDLE_GEMFILE"]
  return given if given && !given.empty?
  find_file("Gemfile", "gems.rb")
end

def in_bundle?
  find_gemfile
end

def pwd
  Bundler.rubygems.ext_lock.synchronize do
    Pathname.pwd
  end
end

def search_up(*names)
  previous = nil
  current  = File.expand_path(SharedHelpers.pwd)
  until !File.directory?(current) || current == previous
    if ENV["BUNDLE_SPEC_RUN"]
      # avoid stepping above the tmp directory when testing
      return nil if File.file?(File.join(current, "bundler.gemspec"))
    end
    names.each do |name|
      filename = File.join(current, name)
      yield filename
    end
    previous = current
    current = File.expand_path("..", current)
  end
end

def set_bundle_environment
  set_bundle_variables
  set_path
  set_rubyopt
  set_rubylib
end

def set_bundle_variables
  begin
    ENV["BUNDLE_BIN_PATH"] = Bundler.rubygems.bin_path("bundler", "bundle", VERSION)
  rescue Gem::GemNotFoundException
    ENV["BUNDLE_BIN_PATH"] = File.expand_path("../../../exe/bundle", __FILE__)
  end
  # Set BUNDLE_GEMFILE
  ENV["BUNDLE_GEMFILE"] = find_gemfile.to_s
end

def set_path
  paths = (ENV["PATH"] || "").split(File::PATH_SEPARATOR)
  paths.unshift "#{Bundler.bundle_path}/bin"
  ENV["PATH"] = paths.uniq.join(File::PATH_SEPARATOR)
end

def set_rubylib
  rubylib = (ENV["RUBYLIB"] || "").split(File::PATH_SEPARATOR)
  rubylib.unshift File.expand_path("../..", __FILE__)
  ENV["RUBYLIB"] = rubylib.uniq.join(File::PATH_SEPARATOR)
end

def set_rubyopt
  rubyopt = [ENV["RUBYOPT"]].compact
  return if !rubyopt.empty? && rubyopt.first =~ %r{-rbundler/setup}
  rubyopt.unshift %(-rbundler/setup)
  ENV["RUBYOPT"] = rubyopt.join(" ")
end

def with_clean_git_env(&block)
  keys    = %w(GIT_DIR GIT_WORK_TREE)
  old_env = keys.inject({}) do |h, k|
    h.update(k => ENV[k])
  end
  keys.each {|key| ENV.delete(key) }
  block.call
ensure
  keys.each {|key| ENV[key] = old_env[key] }
end