Rails: Undefined method `in_pasting?' for Reline::ANSI:Class (NoMethodError) - ruby-on-rails

Question

I have Ruby 2.7.2 and Rails 6.1.3.1 installed on my Ubuntu 20.04 machine. However, when I try to test a ruby command using the command below:
irb
a = 1
I get the error below:
/home/mycomputer/.rbenv/versions/2.7.2/lib/ruby/gems/2.7.0/gems/irb-1.3.5/lib/irb/ruby-lex.rb:50:in block in set_input': undefined method in_pasting?' for Reline::ANSI:Class (NoMethodError)
I am still tryring to fix it, but it's working.

Answer 1

The error was caused by an issue with the reline gem in the Ruby 2.7.2 setup. However, if I switch to another Ruby version (2.6.6) using rbenv global 2.6.6 everything seems to work fine.
Here's how I fixed it:
Solution 1:
Since the reline gem comes with Ruby installations, we will uninstall the ruby 2.7.2 version that is the cause of the issue using rbenv :
rbenv uninstall 2.7.2
Next, reinstall the ruby 2.7.2 version that is the cause of the issue using rbenv :
rbenv install 2.7.2
Afterwhich you will install the version of Bunder and Rails that you are using. In this case, my Rails version is Rails 6.1.3.1:
gem install bundler
gem install rails -v 6.1.3.1
rbenv rehash
You can afterwards, check the version of ruby, bundler and rails that were installed using the command below:
ruby -v
bundler -v
rails -v
This time when you try to test again using irb it should work fine.
Solution 2:
A faster approach will be to uninstall the reline gem in the Ruby 2.7.2 setup using the command below:
gem uninstall reline
And then reinstall it:
gem install reline
Note:
I did not test this to confirm if it fixes the issue.
That's all.
I hope this helps