Plugin cannot be installed, fail with undefined method `group_by' for nil:NilClass (NoMethodError)

[tribbloid]

I'm using vagrant 1.8.1 and Ruby 2.3.0, when I try to install vagrant-aws I get the following error:

~$ vagrant plugin install vagrant-aws
Installing the 'vagrant-aws' plugin. This can take a few minutes...
/usr/lib/ruby/2.3.0/rubygems/specification.rb:946:in `all=': undefined method `group_by' for nil:NilClass (NoMethodError)
    from /usr/lib/ruby/vendor_ruby/vagrant/bundler.rb:275:in `with_isolated_gem'
    from /usr/lib/ruby/vendor_ruby/vagrant/bundler.rb:231:in `internal_install'
    from /usr/lib/ruby/vendor_ruby/vagrant/bundler.rb:102:in `install'
    from /usr/lib/ruby/vendor_ruby/vagrant/plugin/manager.rb:62:in `block in install_plugin'
    from /usr/lib/ruby/vendor_ruby/vagrant/plugin/manager.rb:72:in `install_plugin'
    from /usr/share/vagrant/plugins/commands/plugin/action/install_gem.rb:37:in `call'
    from /usr/lib/ruby/vendor_ruby/vagrant/action/warden.rb:34:in `call'
    from /usr/lib/ruby/vendor_ruby/vagrant/action/builder.rb:116:in `call'
    from /usr/lib/ruby/vendor_ruby/vagrant/action/runner.rb:66:in `block in run'
    from /usr/lib/ruby/vendor_ruby/vagrant/util/busy.rb:19:in `busy'
    from /usr/lib/ruby/vendor_ruby/vagrant/action/runner.rb:66:in `run'
    from /usr/share/vagrant/plugins/commands/plugin/command/base.rb:14:in `action'
    from /usr/share/vagrant/plugins/commands/plugin/command/install.rb:32:in `block in execute'
    from /usr/share/vagrant/plugins/commands/plugin/command/install.rb:31:in `each'
    from /usr/share/vagrant/plugins/commands/plugin/command/install.rb:31:in `execute'
    from /usr/share/vagrant/plugins/commands/plugin/command/root.rb:56:in `execute'
    from /usr/lib/ruby/vendor_ruby/vagrant/cli.rb:42:in `execute'
    from /usr/lib/ruby/vendor_ruby/vagrant/environment.rb:268:in `cli'
    from /usr/bin/vagrant:173:in `<main>'

Please advice me if its a compatibility error.

[sethvargo]

Core issue: https://github.com/mitchellh/vagrant/issues/7073