Why is GITHUB_BASE_REF and GITHUB_HEAD_REF set for PRs in non-forked repositories?

[deanmalan]

What article on docs.github.com is affected?

https://docs.github.com/en/free-pro-team@latest/actions/reference/environment-variables

What part(s) of the article would you like to see updated?

The documentation for GITHUB_BASE_REF and GITHUB_HEAD_REF says that they're both "only set for forked repositories". However, when I create a create a pull request in a repository that is not forked, they are set to the base branch and branch to be merged in, respectively. See an example here.

Is this expected behaviour? If yes, should the docs not be updated to reflect this?

[welcome]

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[StephanBijzitter]

Whether the docs are wrong, or this is a bug, I'm happy they are set.

refs/pull/{id}/merge is quite useless if you just want to grab the branch name quickly.

[lucascosti]

👋 Thanks for opening this issue!

I suspect this is a docs bug, and that it should probably say something like "Only set for pull request events" instead. I'll double-check with our engineering team to make sure that this is the intended behavior 👍

[lucascosti]

Yep, confirmed this is a docs bug! 🐛 Those environment variables are intended to be available for all PRs. I'll get the docs updated.

[deanmalan]

Thanks @lucascosti !

[lucascosti]

Just to close the loop, the fix is now live in production ✅ 🎉: https://docs.github.com/en/free-pro-team@latest/actions/reference/environment-variables#default-environment-variables