assert_equal 'ok', %q{ open("require-lock-test.rb", "w") {|f| f.puts "sleep 0.1" f.puts "module M" f.puts "end" } $:.unshift Dir.pwd vs = (1..2).map {|i| Thread.start { require "require-lock-test" M } }.map {|t| t.value } vs[0] == M && vs[1] == M ? :ok : :ng }, '[ruby-dev:32048]'