Streamline changeset generation with conventional commit support

Affected Packages

@changesets/cli, perhaps a new package would be more appropriate for this functionality

Problem

Our organization has been versioning packages with lerna + conventional commits for a while now, but we are looking at moving towards changesets, mainly because the .changeset/config.json is just awesome. I love how you can make explicit associations between different packages - this is exactly what the conventional commits workflow has been missing imo.

Our developers have become accustomed to the conventional commit workflow and I think that providing an integration could go a long way in terms of facilitating adoption for other organizations as well.

Proposed solution

I am hoping something similar to the following would be possible.

Given some number of conventional commits since master n, and some arbitrary number of packages in a mono-repo, running changeset version should:

1. Visit each of the n commits and determine the proper version bump based on the commit message and affected package. For example, if you have a commit that affects package A: feat: Add some feature to package A, the associated version bump should be translated to a minor bump of package A. Similarly if you have a commit to package B: fix: Fix something, the associated version bump should be translated to a patch bump of package B.

2. Once the version bumps from conventional commits are determined, pre-populate the changeset version prompts with the respective bumps. In the example above with package A, when the prompt asks Which packages should have a minor bump?, package A should already be pre-selected. I would also see this pre-populating the prompt. Please enter a summary for this change (this will be in the changelogs).

I would also hope for a flag that would allow us to auto-generate the changesets from conventional commits (without any additional prompting). That being said, I can see how this specifically may be at odds with the generally recommended changeset workflow.

I am new to changesets, so I am currently unfamiliar with how it is set up, or how much of a shift this would be. Hoping I can get an idea of whether this something that others would find valuable, and/or what changes might be necessary to facilitate this. I am happy to help out however possible with this effort. Alternatively, if there is any sort of plugin-based API for third-party integrations, that may be more appropriate for this use case, but I am unaware of such an API.

Cheers!