Receive syntax error when installing gem on Ruby

Question

I'm trying to install a gem using Ruby. I keep getting a weird syntax error when I do. Using rvm, latest version, to install. The error message is:

  /Users/george/.rvm/rubies/ruby-2.1.5/lib/ruby/2.1.0/psych.rb:370:in `parse': (<unknown>): mapping values are not allowed in this context at line 2 column 30 (Psych::SyntaxError)
    from /Users/george/.rvm/rubies/ruby-2.1.5/lib/ruby/2.1.0/psych.rb:370:in `parse_stream'
    from /Users/george/.rvm/rubies/ruby-2.1.5/lib/ruby/2.1.0/psych.rb:318:in `parse'
    from /Users/george/.rvm/rubies/ruby-2.1.5/lib/ruby/2.1.0/psych.rb:245:in `load'
    from /Users/george/.rvm/rubies/ruby-2.1.5/lib/ruby/site_ruby/2.1.0/rubygems/config_file.rb:333:in `load_file'
    from /Users/george/.rvm/rubies/ruby-2.1.5/lib/ruby/site_ruby/2.1.0/rubygems/config_file.rb:198:in `initialize'
    from /Users/george/.rvm/rubies/ruby-2.1.5/lib/ruby/site_ruby/2.1.0/rubygems/gem_runner.rb:74:in `new'
    from /Users/george/.rvm/rubies/ruby-2.1.5/lib/ruby/site_ruby/2.1.0/rubygems/gem_runner.rb:74:in `do_configuration'
    from /Users/george/.rvm/rubies/ruby-2.1.5/lib/ruby/site_ruby/2.1.0/rubygems/gem_runner.rb:39:in `run'
    from /Users/george/.rvm/rubies/ruby-2.1.5/bin/gem:21:in `<main>'

I also get this error when trying to set rvm to use a different ruby version.

Answer 1

There's an error in your rubygems config file. If you're not using a custom config file, look for a file .gemrc in your home folder. It seems there's incorrect content on line 2.

Psych is a YAML parser, so look for something that is incorrect YAML.

Answer 2

It looks like there was an issue in the .gemrc file as well as some other files created in the root folder that were affecting RVM from installing Ruby correctly.

Re-storing the files to the previous state and removing the junk files with rm -rf got everything working.