Unexpected output from `git rev-parse`: HEAD

[liblaf]

First, thank you for creating and maintaining this useful GitHub Action – it's been a great tool for me! 🙌

I ran into this error:

Error: Unexpected output from `git rev-parse`: HEAD

Here is an example workflow run: https://github.com/liblaf/grapes/actions/runs/15234982862/job/42847606615.

I've also noticed that this error always seems to appear in workflows triggered by a pull_request event.

Hope to find a way to fix it.

Thanks again for your hard work and consideration!

[dsanders11]

I've also noticed that this error always seems to appear in workflows triggered by a pull_request event.

Admittedly this is a use case I haven't tested with the action. I'll see if I can find some time to look into it.

[liblaf]

@dsanders11 I solved this issue by specifying ref when checkout:

- name: Checkout
  uses: actions/checkout@v4
  with:
    ref: ${{ github.head_ref || github.ref }}