rails error, couldn't parse YAML

Question

After updating the gems I've got this:

/home/megas/.rvm/rubies/ruby-1.9.2-p136/lib/ruby/1.9.1/psych.rb:148:in `parse': couldn't parse YAML at line 182 column 9 (Psych::SyntaxError)
    from /home/megas/.rvm/rubies/ruby-1.9.2-p136/lib/ruby/1.9.1/psych.rb:148:in `parse_stream'
    from /home/megas/.rvm/rubies/ruby-1.9.2-p136/lib/ruby/1.9.1/psych.rb:119:in `parse'
    from /home/megas/.rvm/rubies/ruby-1.9.2-p136/lib/ruby/1.9.1/psych.rb:106:in `load'
    from /home/megas/.rvm/gems/ruby-1.9.2-p136/gems/RedCloth-4.2.3/lib/redcloth/formatters/latex.rb:6:in `<module:LATEX>'
    from /home/megas/.rvm/gems/ruby-1.9.2-p136/gems/RedCloth-4.2.3/lib/redcloth/formatters/latex.rb:3:in `<top (required)>'
    from /home/megas/.rvm/gems/ruby-1.9.2-p136/gems/RedCloth-4.2.3/lib/redcloth.rb:21:in `require'
    from /home/megas/.rvm/gems/ruby-1.9.2-p136/gems/RedCloth-4.2.3/lib/redcloth.rb:21:in `<top (required)>'
    from /home/megas/.rvm/gems/ruby-1.9.2-p136/gems/RedCloth-4.2.3/lib/case_sensitive_require/RedCloth.rb:6:in `require'
    from /home/megas/.rvm/gems/ruby-1.9.2-p136/gems/RedCloth-4.2.3/lib/case_sensitive_require/RedCloth.rb:6:in `<top (required)>'
    from /home/megas/.rvm/gems/ruby-1.9.2-p136/gems/bundler-1.0.10/lib/bundler/runtime.rb:68:in `require'
    from /home/megas/.rvm/gems/ruby-1.9.2-p136/gems/bundler-1.0.10/lib/bundler/runtime.rb:68:in `block (2 levels) in require'
    from /home/megas/.rvm/gems/ruby-1.9.2-p136/gems/bundler-1.0.10/lib/bundler/runtime.rb:66:in `each'
    from /home/megas/.rvm/gems/ruby-1.9.2-p136/gems/bundler-1.0.10/lib/bundler/runtime.rb:66:in `block in require'
    from /home/megas/.rvm/gems/ruby-1.9.2-p136/gems/bundler-1.0.10/lib/bundler/runtime.rb:55:in `each'
    from /home/megas/.rvm/gems/ruby-1.9.2-p136/gems/bundler-1.0.10/lib/bundler/runtime.rb:55:in `require'
    from /home/megas/.rvm/gems/ruby-1.9.2-p136/gems/bundler-1.0.10/lib/bundler.rb:120:in `require'
    from /home/megas/Work/railscasts/config/application.rb:10:in `<top (required)>'
    from /home/megas/.rvm/gems/ruby-1.9.2-p136/gems/railties-3.0.3/lib/rails/commands.rb:28:in `require'
    from /home/megas/.rvm/gems/ruby-1.9.2-p136/gems/railties-3.0.3/lib/rails/commands.rb:28:in `block in <top (required)>'
    from /home/megas/.rvm/gems/ruby-1.9.2-p136/gems/railties-3.0.3/lib/rails/commands.rb:27:in `tap'
    from /home/megas/.rvm/gems/ruby-1.9.2-p136/gems/railties-3.0.3/lib/rails/commands.rb:27:in `<top (required)>'
    from script/rails:6:in `require'
    from script/rails:6:in `<main>'

ruby-1.9.2-p136 rails 3.0.3

Tried to reinstall gem RedCloth, didn't help, system wants to use only 4.2.3 version

Any idea how to fix it? Thanks

Answer 1

You have invalid YAML code somewhere. I mean invalid for Psych (the new ruby YAML parser).

If you cannot (or don't want to) fix your YAML code, try to load the old YAML parser (syck), adding this at the beginning of config/boot.rb

require 'yaml'
YAML::ENGINE.yamler = 'syck'

It's just a 'quick and dirty' fix, I know