[PR description] Rethink or at least re-run

[sethvargo]

TL;DR

I understand the intention of the PR description check, but it's actually quite annoying for small changes. For example, https://github.com/abcxyz/infra-github/pull/196 is very self-explanatory. The original commit and title of the PR was "Archive customer-engineering-poc (no longer used)". There didn't seem to be a need for a PR description that wasn't purely duplicative with the title. But the check failed...

Nonetheless, I moved the "no longer used" part into the PR description, but that doesn't trigger the check to re-run. So if you omit a PR description, you're left manually re-running the workflow, which feels really less than ideal.

My suggestion is that we use PR Templates instead of this GitHub Action to achieve the same intent. Or at the very least, reduce this to a warning instead of a blocking error.

Expected behavior

No response

Observed behavior

No response

Environment Details

GitHub Actions

Additional information

No response

[sethvargo]

Well, it got worse: https://github.com/abcxyz/actions/actions/runs/14722721706/job/41319391724?pr=58

Run ./.github/actions/pull-request-lint
Run if [[ -z "Un-breaking the build (sorry @pdewilde). Apparently the default version of shellcheck installed on the runners is too old and [doesn't have the `--rcfile` flag](https://github.com/abcxyz/infra-github/actions/runs/14722558591/job/413191311[34](https://github.com/abcxyz/actions/actions/runs/14722721706/job/41319391724?pr=58#step:3:35)?pr=196). We didn't catch this in presubmits because that codepath isn't executed.
/home/runner/work/_temp/a8769c60-6ff6-46fb-9d38-7bfbc59d5cc7.sh: line 27: unexpected EOF while looking for matching ``'
Error: Process completed with exit code 2.

I am going to disable this checker until we can decide if it's adding value.

[sethvargo]

#59 fixes the shell escaping. Can we please seriously stop passing in inputs or untrusted contexts into the scripts?

[dcreey]

I have not encountered an issue with the workflow not re-running. When I update a PR description it automatically re-runs. Perhaps there was some latency in the job running (github-side).

Some ideas for improving the experience:

1. Make it a warning, as you suggested. We can add a comment with suggestions/changes that you could consider making to the PR. And we can link to more details for supported features in a PR (especially if its your first commit).
2. Only block if the PR is sufficiently large enough and the title does not contain revert. We could arbitrarily pick >= 50 loc changed.
3. Automatically generate a PR description using gemini and update the PR with it.

[sethvargo]

#62, but I found other issues...