class Jeweler::Tasks

def yield_gemspec_set_version?
  yielded_gemspec = @gemspec.dup
  yielded_gemspec.extend(Jeweler::Specification)
  yielded_gemspec.files = FileList[]
  yielded_gemspec.extra_rdoc_files = FileList[]
  gemspec_building_block.call(yielded_gemspec) if gemspec_building_block
  ! yielded_gemspec.version.nil?
end