Preserving upstream README, CHANGELOG, etc. files in a fork using Actions.

[erictheise]

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I'm working on a forked project. While we may occasionally contribute to the upstream project the main purpose of our fork is adding functionality that is not appropriate for the upstream one. I want to use GitHub Actions to periodically pull in upstream changes and run tests in an attempt to stay in sync. Common use case.

As part of this I'd like to keep standard upstream files but also have our own that take precedence. What I mean by that is the upstream README.md, CHANGELOG.md, LICENCE, TODO.md, etc. should be available in our repo, say in an /upstream subdirectory, and that ours should be at the root level of the project.

What are the best ways of accomplishing this kind of renaming/moving/preserving upstream files? Thanks in advance.

[spenserblack]

An interesting one for sure!

To run periodically, you probably want to run your action on a schedule.

But, as far as what to actually run on the schedule, here are some git commands that might help you:

• git merge --no-ff --no-commit SOURCE: Start a merge, but make sure that the merge is paused
  • --no-ff ensures that the merge isn't fast-forwarded. It will stop git from placing the new commits on top of your current commits without a merge commit.
  • --no-commit ensures that git doesn't automatically try to create a commit when merging
• git checkout [--ours|--theirs] -- FILEPATH: this allows you to checkout a file from a "side" of the pending commit. It's probably easiest to understand by playing around with this.

I'd recommend writing a shell script that:

1. Fetches the upstream
2. Starts a merge
3. Runs git checkout --theirs (or --ours) on the appropriate files.
4. Commits the merge

This way you can easily play around with this script locally, and when you're satisfied with its behavior you can write an action to run this script on a schedule.