diff --git a/railties/lib/rails/test_unit/railtie.rb b/railties/lib/rails/test_unit/railtie.rb
index 9cc3f73a9c69c80a67dfb90d607c58b349e6fcca..443e7434219bf90e665bf8e9b447f38019aa00b4 100644
--- a/railties/lib/rails/test_unit/railtie.rb
+++ b/railties/lib/rails/test_unit/railtie.rb
@@ -1,7 +1,7 @@
 require "rails/test_unit/line_filtering"
 
 if defined?(Rake.application) && Rake.application.top_level_tasks.grep(/^(default$|test(:|$))/).any?
-  ENV["RAILS_ENV"] ||= "test"
+  ENV["RAILS_ENV"] ||= Rake.application.options.show_tasks ? "development" : "test"
 end
 
 module Rails