log to fake_app/log directory

spec/fake_app/rails_app.rb

@@ -11,6 +11,8 @@ app = Class.new(Rails::Application)
 app.config.secret_token = '3b7cd727ee24e8444053437c36cc66c4'
 app.config.session_store :cookie_store, :key => '_myapp_session'
 app.config.active_support.deprecation = :log
+# Rais.root
+app.config.root = File.dirname(__FILE__)
 Rails.backtrace_cleaner.remove_silencers!
 app.initialize!