Add pre-commit auto-update workflow

[forsyth2]

Add pre-commit auto-update workflow by copying changes from equivalent zppy-interfaces PR:
E3SM-Project/zppy-interfaces#57. Other equivalent PRs: E3SM-Project/zppy#853, E3SM-Project/zstash#454

[forsyth2]

Using this branch as-is, I'm unable to build a conda env:

rm -rf build
conda clean --all --y
conda env create -f conda/dev.yml -n e3sm-comms-pre-commit-20260813
# CondaError: Cannot link a source that does not exist.

[Copilot]

Pull request overview

Adds automation to keep QA tooling versions consistent across .pre-commit-config.yaml, conda/dev.yml, and the qa extra in pyproject.toml, and introduces a scheduled GitHub Actions workflow to run pre-commit-update and open an auto-update PR.

Changes:

• Add scripts/sync_pre_commit_versions.py to propagate pre-commit hook rev bumps into conda/dev.yml and pyproject.toml (qa extra).
• Introduce a scheduled/manual GitHub Actions workflow to run pre-commit-update, sync versions, push a branch, and open a PR.
• Minor config/documentation updates, including adding types-PyYAML for the mypy pre-commit hook.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
scripts/sync_pre_commit_versions.py	New script to sync pinned tool versions from .pre-commit-config.yaml into other dependency definitions.
pyproject.toml	Adds a note pointing to the sync script for keeping qa deps aligned.
conda/dev.yml	Updates instructions to use the sync script after pre-commit autoupdate.
.pre-commit-config.yaml	Adds a note about syncing and adds types-PyYAML to mypy hook deps.
.github/workflows/pre_commit_update_workflow.yml	New scheduled workflow to auto-update pre-commit hooks and open a PR.

Suppressed comments (2)

.github/workflows/pre_commit_update_workflow.yml:90

• gh pr create will fail the workflow if a PR for update-pre-commit-deps already exists (common when a previous auto-update PR is still open). Add a guard to skip creation (or edit the existing PR) when one already exists so scheduled runs don’t fail noisily.

          gh pr create \
          --title "Update pre-commit and its dependencies" \
          --body "This PR was auto-generated to update pre-commit and its dependencies." \
          --head update-pre-commit-deps \
          --reviewer ${{ env.REVIEWERS }} \

.github/workflows/pre_commit_update_workflow.yml:57

• This step clones the repository again via HTTPS without pinning a ref/SHA, which ignores the ref checked out by actions/checkout and will always use the default branch (especially surprising for workflow_dispatch runs on non-default refs). It’s also redundant work. Prefer operating on the already checked-out workspace (or check out into update-pre-commit-deps via actions/checkout with path:/ref:) and adjust the later directory:/cd usages accordingly.

          git clone https://github.com/E3SM-Project/e3sm-comms.git update-pre-commit-deps
          cd update-pre-commit-deps

---

💡 Add a code-review agent skill or configure MCP servers for context-aware, tailored reviews. Learn more in the docs.

[xylar]

A few things like in the others.

[forsyth2]

Confirmed I could create a conda env and pre-commit passes in it.