bundler requires RubyGems version >= 3.0.0

[thbar]

On an existing Ansible setup using this role, or for a fresh install, I'm getting this error:

TASK [rvm_io.ruby : Install bundler if not installed] ******************************************************************************************
# SNIP
  stderr: |-
    ERROR:  Error installing bundler:
            The last version of bundler (>= 0) to support your Ruby & RubyGems was 1.17.3. Try installing it with `gem install bundler -v 1.17.3`
            bundler requires RubyGems version >= 3.0.0. The current RubyGems version is 2.7.6. Try 'gem update --system' to update RubyGems itself.

If I understand correctly, this will affect anyone using this role without rvm1_bundler_install: False.

My understanding is that the available fixes are:

• Modifying the role to freeze the version of bundler (like hinted in #191)
• Modifying the role to upgrade rubygems to a specific version (e.g. 3.0.2) right before doing bundle install (ideally a version passed by the user, in idempotent fashion)
• Using rvm1_bundler_install: False then a custom task to install the relevant version for each installed ruby

I will likely attempt to use the third solution for now, but wanted to document this since it will likely affect other rubyists.

[thbar]

There will be a bundler fix to avoid this problem https://github.com/bundler/bundler/pull/6867

[thbar]

The release of bundler v2.0.1 solves this for me.

Ideally, being able to pass a version (like in #191, but optional) would be great.

I'll close this for now.