Migrating a Tap's default branch from master to main

[jasonkarns]

Output of brew config

n/a

Output of brew doctor

n/a

Description of issue

I'm the maintainer of a couple 3rd party taps, each of which currently have master as their default branch.

I noticed that the current tap-new command creates a tap with main as the default branch. I'm curious if homebrew has any support or steps for safely migrating from master to main as the tap's default branch.

If I use github's own branch renaming capability, will users who already have my taps cloned automatically be updated? (ie, does homebrew itself detect the branch name change?)

If not, is there any longer term transition process that would allow, say, changing the default branch to main, and then keeping master branch in sync for a while to give users a chance to change their clones? (I have successfully used github actions to force-push master to keep it in sync with main for a number of months. That way the master branch continues to exist for a while longer, even after it's no longer the default branch.)

Any other guidance or stories from other tap maintainers?

[p-linnane]

@MikeMcQuaid has actually been working on this across our repos. Check the release notes for Homebrew 4.5.7 for a list of PR's: https://github.com/Homebrew/brew/releases/tag/4.5.7

[MikeMcQuaid]

Yes, thanks @p-linnane. Here's the current state of things: Homebrew/brew#17296

You should now just be able to rename your tap's branch and anyone on Homebrew >=4.5.7 will get it updated automatically and anyone on an older version will need to run brew update twice or brew tap --repair.

[jasonkarns]

That's awesome, thank you both!

It seems I waited the exact amount of time to do this rename on my taps. 😄