Marko Anastasov wrote this on March 17, 2011
Psych syntax errors with Ruby 1.9 and Rails 3
We love using the latest versions of our tools but sometimes they’re giving us a hard time. If you’re using Bundler 1.0.10, Rails 3.0.x and Ruby 1.9.2, and you’re dealing with some YAML, eg through fixtures or seed data, you’re likely to encounter a
Psych::SyntaxError with a stack trace that doesn’t help.
The first time, more than a month ago, we worked around it, but it hit us again yesterday and we found a solution on StackOverflow. The thing is that Bundler 1.0.10 loads Psych as a YAML engine which doesn’t work well with Rails, and for now, we should be using Syck instead.