1 files changed, 4 insertions, 0 deletions
diff --git a/railties/test/env_helpers.rb b/railties/test/env_helpers.rb
index 6223c85bbf..330fe150ca 100644
--- a/railties/test/env_helpers.rb
+++ b/railties/test/env_helpers.rb
@@ -1,7 +1,10 @@
+require 'rails'
+
 module EnvHelpers
   private
 
   def with_rails_env(env)
+    Rails.instance_variable_set :@_env, nil
     switch_env 'RAILS_ENV', env do
       switch_env 'RACK_ENV', nil do
         yield
@@ -10,6 +13,7 @@ module EnvHelpers
   end
 
   def with_rack_env(env)
+    Rails.instance_variable_set :@_env, nil
     switch_env 'RACK_ENV', env do
       switch_env 'RAILS_ENV', nil do
         yield