upload: Check PRs merge into base branch rather than base ref

[jerry-skydio]

The logic for checking whether a PR was improperly merged was allowing
the target branch name, which could be a relative branch. We don't want
that, we only want changes to merge into the base branch of the entire chain.

This also helps handle some reordering issues.

Topic: reorder3
Reviewers: aaron, brian-k

[jerry-skydio]

Reviews in this chain:
└#207 upload: Check PRs merge into base branch rather than base ref

[jerry-skydio]

#	head	base	diff	date	summary
0	98a104eb	159f964c	diff	Dec 30 15:28 PM	1 file changed, 2 insertions(+), 2 deletions(-)

[aaron-skydio]

Hmm. I think it should be fine to merge into either the base branch, or the review.remote_base? For example, sometimes I'll upload a PR relative to someone else's PR as a suggestion/demo, with the intent that they'll merge my PR into theirs before merging theirs into its base. And that sort of thing should be fully revup-supported with #205 (you could already do it with two of your own PRs but I don't have a use case for that)

[jerry-skydio]

if you intend to use the github merge UI you should be using base_branch rather than relative or relative-branch, as the main difference between these is how revup thinks you intended to merge things into them, and how revup should react

base-branch : you intend to merge into this. if pr is merged, revup does not re-create it
relative-branch : you want your diff to be relative, but intend to merge into some other base branch. if relative-branch itself is merged, it is ignored. if your pr gets merged, revup re-creates it
relative : similar to above, but you also control the relative branch / it is created via revup itself. if your pr gets merged, revup re-creates it

[jerry-skydio]

specifically #205 is for when you intend to take over someone else's branch (and this confusion aspect was probably why i didn't originally allow this). if you don't intend to take over the branch you should still use relative-branch (or base-branch perhaps). this is because 2 people pushing to a branch will be confusing -- revup makes no attempt to integrate the push efforts of 2 different uploaders working simultaneously

[aaron-skydio]

Good point, if you're relative to someone else's branch using uploader (which would mean you're planning to push that branch) you might as well just push to that directly instead of creating and merging a PR