Warning. Error encountered while saving cache … can't dump anonymous class

Question

When app is deployed with capistrano errors occur in production.log.

Compiled signup.css  (30ms)  (pid 31797)
Warning. Error encountered while saving cache /         


        

Answer 1

It is a bug in sprockets, but if, like me you are using an older version of Rails (3.2) you may be able to fix the bug by using a different version of sass. This guy was able to get it working with sass 3.1.x: https://github.com/rails/sass-rails/issues/242#issuecomment-66231135

The thread mentioned there gives some good context and an explanation for how to handle solving the issue or working around an inability to upgrade to a much newer, fixed version of sprockets.

Basically, use sass/sass-rails/sprockets from around the time Rails 3.2.x was supported.