class Gem::Source::Git

def specs
  checkout
  return [] unless install_dir
  Dir.chdir install_dir do
    Dir['{,*,*/*}.gemspec'].map do |spec_file|
      directory = File.dirname spec_file
      file      = File.basename spec_file
      Dir.chdir directory do
        spec = Gem::Specification.load file
        if spec
          spec.base_dir = base_dir
          spec.extension_dir =
            File.join base_dir, 'extensions', Gem::Platform.local.to_s,
              Gem.extension_api_version, "#{name}-#{dir_shortref}"
          spec.full_gem_path = File.dirname spec.loaded_from if spec
        end
        spec
      end
    end.compact
  end
end