I'm thinking of producing output for beginners, I am writing an article. I'm a complete amateur who hasn't been to the scene yet. If you make a mistake, I would appreciate it if you could comment.
When I tried to install docker-compose in my development environment, I was angry that the version of bundler was wrong. And I decided to change the version of bandler, but there was surprisingly little information. So, for those who need to switch the version of bundler, I am posting an article as a reference.
Ruby: 2.6.5 Ruby on Rails: 6.0.0
There are 4 steps, but it's easy, so you can do it in an instant.
$ gem search ^bundler$ --all
All the versions you can install will come, so find the version you need.
$ gem install bundler -v '1.3.4'
The quoted version is installed.
$ rm Gemfile.lock
Rest assured that even if you delete it, it will be generated at bundle install.
$ bundle _1.3.4_ install
This should change the description of Gemfile.lock as well,
⚠️ Please use the appropriate version for all versions.