I have a problem with the 'update' hook. In the case of a new branch, it gets a 0000000000000000000000000000000000000000 as the 'oldrev'. And I don't know how to handle that case.
We have the requirement, that every commit message references a valid Jira issue. So I have installed an "update" hook on our central repository. That hook gets an "oldrev" and a "newrev". I then pass those to "git rev-list" like this:
git rev-list $oldrev..$newrev
This gives me the list of all revs, which I can then iterate through, and do whatever I need to do.
The problem is, when the user pushes a new branch, the hook gets 0000000000000000000000000000000000000000 as the oldrev. And "git rev-list" simply complains with:
fatal: Invalid revision range 0000000000000000000000000000000000000000..21bac83b2
So how do I get the list of all the revs that are on that new branch? I have searched the net for quite some time now, and found nothing. The example hooks I found either
- don't handle the problem, and fail with the above error message
- incorrectly try to fix the problem by setting the oldrev to "", which returns the wrong results from rev-list
- simply give up when they encounter that oldrev
None of these sound particularly exciting.
So does someone have any idea how to get the right answer in that case? I was thinking about querying git for "give me all revs that are reachable from newrev, but not from any of the other branches (=all branches except the new one)". But even that would give the wrong answer if there had been a merge from the new branch to any of the old ones.