gistfile1.rb

class SubversionDownloadStrategy <AbstractDownloadStrategy
  def initialize url, name, version, specs
    @name = name
    super url, name, version, specs
  end

  def fetch
    ohai "Exporting #{@url}"
    @export = HOMEBREW_CACHE+@unique_token
    if @spec == :revision
      args = [svn, 'export', '--force', @url, @export]
      args << '-r' << @ref if @ref
      quiet_safe_system *args
    elsif @spec == :revisions
      externals = Hash.new
      # Should I do forking and piping instead. Anyone have anything against 
      # backticks?
      `#{svn} propget svn:externals #{@url}`.each_line do |external_line|
        key, value = external_line.split /\s+/
        externals[key] = value
      end
      @ref.each_pair do |directory, revision|
        if directory.to_s == @name
          directory = ''
        else
          directory = directory.to_s
        end
        svnurl = @url
        svnurl = externals[directory] unless directory == ''
        args = [svn, 'export', '--force', '--ignore-externals', svnurl, @export+directory]
        args << '-r' << revision
        quiet_safe_system *args
      end
    else
      args = [svn, 'export', '--force', @url, @export]
      quiet_safe_system *args
    end
  end

  def stage
    # Would be nice if we could cache and verify the export, then copy it in 
    # stage without downloading it again if it was OK, but I cannot think how 
    # to verify the cache. No way sane, atleast.
    FileUtils.cp_r @export.to_s + '/.', Dir.pwd
  end

  # Override this method in a DownloadStrategy to force the use of a non-
  # sysetm svn binary. mplayer.rb uses this to require a svn that
  # understands externals.
  def svn
    '/usr/bin/svn'
  end
end