Re: Able to checkout same branch in multiple worktrees when using symbolic-refs
- From
Junio C Hamano <gitster@pobox.com>
- Date
- Apr 29, 2022, 20:19 UTC
- Message-ID
- <xmqqsfpvabib.fsf@gitster.g>
- In-Reply-To
- <CAAir=1MbwGtONW7yWRWoXKzAiwqwhOAqdhfWYMYLxt1vANuUOA@mail.gmail.com>
Austin Morton <austin.morton@aquatic.com> writes:
> When using a symbolic-ref I am able to inadvertently checkout the same > branch in multiple worktrees when using the symbolic-ref name, despite > being prevented from doing so if I use the target branch name.
Don't do that if it hurts ;-)
If you checked out 'main' in the secondary worktree and made a commit there, the symbolic-ref makes 'master' to be updated, confusing the primary worktree whose index and the working tree files record work relative to the old commit before the secondary worktree updated it via the symbolic-ref, which is exactly the same situation that the "do not check out the same branch in two different worktrees" protection tries to save the user from, but I do not think we currently do so.
Because this "do not check a branch out twice and let it be futzed with from the two places" is primarily a mechanism to help inexperienced users from getting confused (and there is an escape hatch mechanism to allow it to those who know what they are doing), and use of symbolic-ref to make 'main' and 'master' synonyms with each other is not something inexperienced users who have no clue on what they are doing would be doing anyway, it may not be a huge deal.
I also suspect there is no way, other than scanning _all_ the local branches, to see if some other branch aliases the branch we are about to check out. It may potentially be somewhat expensive.
But it would be nice if it can get fixed in inexpensively.
Thanks for a report.
Show 20 quoted lines
> Below is a minimal reproducer: > > $ git --version > git version 2.36.0 > $ git init . > $ git status > $ git commit --allow-empty -m "Initial commit" > $ git symbolic-ref refs/heads/main refs/heads/master > $ git worktree add ../worktree2 > $ git worktree list > /home/amorton/test/worktree1 cd8312d [master] > /home/amorton/test/worktree2 cd8312d [worktree2] > $ cd ../worktree2 > $ git checkout master > fatal: 'master' is already checked out at '/home/amorton/test/worktree1' > $ git checkout main > Switched to branch 'main' > $ git worktree list > /home/amorton/test/worktree1 cd8312d [master] > /home/amorton/test/worktree2 cd8312d [master]