diff --git a/railties/test/generators/app_generator_test.rb b/railties/test/generators/app_generator_test.rb
index 26e912fd9e37e..5534476a6dca2 100644
--- a/railties/test/generators/app_generator_test.rb
+++ b/railties/test/generators/app_generator_test.rb
@@ -246,7 +246,7 @@ def test_inclusion_of_javascript_runtime
     if defined?(JRUBY_VERSION)
       assert_gem "therubyrhino"
     else
-      assert_file "Gemfile", /# gem\s+["']therubyracer["']+, platform: :ruby$/
+      assert_file "Gemfile", /# gem\s+["']therubyracer["']+, platforms: :ruby$/
     end
   end