# File lib/rubygems.rb, line 641 def self.required_location(gemname, libfile, *version_constraints) version_constraints = Gem::Requirement.default if version_constraints.empty? matches = Gem.source_index.find_name(gemname, version_constraints) return nil if matches.empty? spec = matches.last spec.require_paths.each do |path| result = File.join(spec.full_gem_path, path, libfile) return result if File.exist?(result) end nil end