Setup

I'm using rev: some_commit_sha in .pre-commit-config.yaml.

I can't use a tag because the latest tag doesn't contain a feature I need. I would rather use a stable revision over the unstable pointer to the master/main branch because this is better practice and ensures everyone using the repository is working with the same pre-commit hooks.

Problem

The autoupdate feature of [pre-commit.ci] is issuing a PR asking to upgrade the revision to the latest tag. However the latest tag is older than the revision I have pinned, so moving to the latest tag would actually be a downgrade not an upgrade.

Full example

I'm using black_nbconvert to automatically blacken notebooks. It's a great tool, but not seen any updates in the last 2 years. The latest release (v0.2.0, Oct 2019) can't handle notebook cells containing cell magic, whereas the bleeding-edge version can.

Contents of .pre-commit-config.yaml:

repos:
  - repo: https://github.com/dfm/black_nbconvert
    rev: dcd7789
    hooks:
      - id: black_nbconvert

PRs issued by pre-commit.ci here rochefort-lab/fissa#196 and rochefort-lab/fissa#216 both want to do github.com/dfm/black_nbconvert: dcd7789 → v0.2.0 which is a downgrade.
If you reverse the comparison you can see the two commits which are being dropped by the autoupdate PR.

I've asked the author of black_nbconvert to release a new tag with cell magic support (dfm/black_nbconvert#3), which would solve things for this one pre-commit hook but not the problem in general.

What is the best solution? Maybe autoupdate should never try to change revisions which have been pinned to a tag, but to never change revisions pinned to a commit SHA? I'm not sure if this is best, but what seems clear is that autoupdate should not issue a PR asking for a revision to be changed to one that corresponds to an older revision which loses commits without adding any new ones.

Apologies if this is not the right place for pre-commit.ci autoupdate issues. I couldn't see somewhere else to put this.