Test-infra: Tide labels to override for all merge methods

[deadmoose]

Right now, it's possible to use tide/squash to manually override the repository's merge method and squash instead:
https://github.com/kubernetes/test-infra/blob/master/prow/tide/tide.go#L821-L829

In our use, we generally want to squash by default but occasionally override to rebase & keep the individual commits.

[stevekuznetsov]

/area prow/tide
/cc @cjwagner

[cjwagner]

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[cji]

👋 Hello!

I was looking to work on this issue, but wanted to clarify slightly before getting started.

Is the proposal to change the default merge_method for all repositories from merge to squash and then instead of a SquashLabel have a RebaseLabel to override the default for a particular commit (instead of overriding the merge method for the repository as a whole)?

Or should we leave the default merge, allowing users to override that at the repository level with squash in the config, but then also have a RebaseLabel to be used on specific commits?

[stevekuznetsov]

@cji hey! Today, getting the default to squash is as simple as changing the configuration, so I don't think we want to change the default. Instead, we should honor a tide/rebase label that overrides a config-set default of squash for a PR.

[cji]

@stevekuznetsov awesome, will work on implementing that. Thanks for the help clarifying!

[deadmoose]

Instead, we should honor a tide/rebase label that overrides a config-set default of squash for a PR.

Exactly. Today tide/squash ignores the default and overrides to squash. There should be a tide/rebase to override and do that. And similarly, a tide/merge (except that it's an ugly name :/ ) to do _that_.

I personally don't care about that last one, but having support for 2/3 of the options is even weirder than today's support for 1/3.

[fejta]

/lifecycle active

Good luck! May be worth a quick Google doc or issue explain how you intend to solve this before starting on the PR (vs just sending over the solution)

[cji]

Cool, thanks for the suggestion @fejta! - I started riffing on a couple of options here

[deadmoose]

:+1:

Thanks @cji!