Keep generating a Gemfile in bundle init for Bundler 2 and add an option to generate gems.rb

[colby-swandale]

What was the end-user problem that led to this PR?

The bundle init command in Bundler 2 currently generates a gems.rb file by default. The issue with this is that i believe we're pushing gems.rb as a "successor" to the Gemfile that everyone should be using even though there is no real incentive for nearly any ruby project to do so.

All the documentation on the internet about the the gemfile is referred to as Gemfile which I can see will confuse new users to Ruby. If they're looking to add a gem to their project and see the project's README there is a very good chance it will say to "add to the Gemfile and run bundle install" Example 1, Example 2 people will get confused from this. Or if they're learning Bundler for the first time and come across a blog post that talks about the gemfile which is actually gems.rb in their project will also cause confusion for the user.

The last issue i see is that we'll be creating a situation where a lot of projects will be using Gemfile and others will be using gems.rb and that this transition may never be complete because the incentive is just not there.

I believe these issues outweigh the benefit of forcing gems.rb onto users in the UI and I want to propose that we instead have bundle init keep generating a Gemfile as it has been but introduce an option to generate a gems.rb if the user needs it.

(Note: the bundle gem command is un-effected as we didn't get around to update the command to use gems.rb in Bundler 2)

What is your fix for the problem, implemented in this PR?

Make bundle init continue to generate a Gemfile by default and add an option to allow generating a gems.rb file if needed.

cc @indirect @segiddins

[segiddins]

I think I agree with this line of reasoning?

[colby-swandale]

@segiddins did you have any questions?

[indirect]

I think I'm okay with this. In the interests of reducing surprise, shipping 2.x without making gems.rb the default seems reasonable. Then we can have the discussion about possibly changing the default again when we get to 3.0. 🙂

[indirect]

After thinking about this for a few more minutes, I personally would like to be able to set a config flag with the same effect as --gemsrb. Can we keep the code that makes it a setting, but remove the default value change for Bundler 2?

[segiddins]

@colby-swandale no questions. Just saying I think I agree, but I'm not 100% sure what the right thing to do is :)

[bundlerbot]

☔ The latest upstream changes (presumably #6266) made this pull request unmergeable. Please resolve the merge conflicts.

[deivid-rodriguez]

I agree with this PR in combination with @indirect's suggestion of keeping the feature flag! 👍

[indirect]

@colby-swandale still interested in re-enabling the feature flag and merging this?

[colby-swandale]

i'll put the setting back.

[deivid-rodriguez]

This PR was superseded by #7113, which implements the same line of reasoning, so closing!