Rails 3.1 Possible Bug in Asset Pipeline and Uglifier

Question

I ran into a problem deploying on Heroku do to a failure in the rake task

rake assets:precompile

At the bottom is the error I get if I inte

Answer 1

If anyone reading this thread encounters issues with unicode characters or "invalid byte sequence in UTF-8" in your rails app, try putting this in your production.rb file:

# override default uglifier options so we don't mangle unicode
  config.assets.js_compressor = Uglifier.new(output: {ascii_only: true})

In my case, the uglifier was converting strings in my javascript like \udbff into UTF-8 characters í¯¿ which ultimately was breaking some unicode regex. (This was happening with turbo-sprockets and codemirror but you might encounter it anytime your javascript relies on ASCII representations of unicode characters.)