diff --git a/test/rubygems/test_gem_commands_install_command.rb b/test/rubygems/test_gem_commands_install_command.rb
index b3062b4b0d..c12b17e613 100644
--- a/test/rubygems/test_gem_commands_install_command.rb
+++ b/test/rubygems/test_gem_commands_install_command.rb
@@ -1,5 +1,6 @@
 require 'rubygems/test_case'
 require 'rubygems/commands/install_command'
+require 'rubygems/request_set'
 require 'rubygems/rdoc'
 
 class TestGemCommandsInstallCommand < Gem::TestCase