Rails 5 Heroku deploy error: ExecJS::ProgramError: SyntaxError: Unexpected token: name (autoRegisterNamespace)

Question

When trying to deploy a rails 5 app to heroku, I get the following error, when it reaches Running: rake assets:precompile:

remote:        ExecJS         


        

Answer 1

I also had this issue.

It's important to remember that by default Heroku is precompiling in a production environment. When you run rake assets:precompile locally it's typically a development environment, which for me didn't exhibit the issue.

So in order to reproduce the issue locally, try

RAILS_ENV=production rake assets:precompile --trace