Update git-cms-init

[fwyzard]

Better fix for the issue reported at #99 (comment), which does not break git-cms-init for non cms-sw master repositories and with the added advantage of using a standard git command instead of an ad-hoc sequence of "plumbing" git commands.

[cmsbuild]

A new Pull Request was created by @fwyzard (Andrea Bocci) for branch master.

@cmsbuild, @smuzaffar, @gudrutis, @mrodozov can you please review it and eventually sign? Thanks.
You can sign-off by replying to this message having '+1' in the first line of your reply.
You can reject by replying to this message having '-1' in the first line of your reply.

external issue cms-sw/cmsdist#4308

[smuzaffar]

@fwyzard , aren't we going to miss the updates already merged in $CMSSW_BRANCH branch? I thought that running git read-tree -mu HEAD after the creation of from-$CMSSW_TAG branch was needed to get the already merged PRs?

[fwyzard]

As far as I can tell, git read-tree -mu HEAD is only needed to update the list of checked out files when we change the sparse checkout.

Doing

git checkout $CMSSW_TAG -b from-$CMSSW_TAG

should be equivalent to

git branch from-$CMSSW_TAG $CMSSW_TAG
git symbolic-ref HEAD refs/heads/from-$CMSSW_TAG
git reset --hard $CMSSW_TAG

but simpler.

What do you mean by

the updates already merged in $CMSSW_BRANCH branch?

[smuzaffar]

@fwyzard , see the cms-bot message here cms-sw/cmssw#24429 (comment) ?

[fwyzard]

As far as I can see it says

+1 Tested at: 4bec48b https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-24429/30181/summary.html The following merge commits were also included on top of IB + this PR after doing git cms-merge-topic: edb9f98 b31d805 af20b1d 19ae827 111cd66 You can see more details here: https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-24429/30181/git-log-recent-commits https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-24429/30181/git-merge-result

What should I be looking at ?

[smuzaffar]

I mean the extra merge commits on top of IB. My only concern is that, after your changes, are we still going to get these extra commits (if any) while testing PRs?

[fwyzard]

I guess you can give it a try before merging ?

On the other hand, git-cms-init creates a branch that points to the release tag - anything on top should be explicitly requested.

As for the release branch (e.g. CMSSW_10_3_X) I always assumed that git-cms-init would create it and leave it pointing to the same commit the release, not the HEAD.