On Thu, Jun 20, 2019 at 9:02 PM Derrick Stolee <stolee@xxxxxxxxx> wrote: > > On 6/20/2019 5:55 AM, Nguyễn Thái Ngọc Duy wrote: > > In c45f0f525d (switch: reject if some operation is in progress, > > 2019-03-29), a check is added to prevent switching when some operation > > is in progress. The reason is it's often not safe to do so. > > > > This is true for merge, am, rebase, cherry-pick and revert, but not so > > much for bisect because bisecting is basically jumping/switching between > > a bunch of commits to pin point the first bad one. git-bisect suggests > > the next commit to test, but it's not wrong for the user to test a > > different commit because git-bisect cannot have the knowledge to know > > better. > > When a user switches commits during a bisect, it can just create new > known-good or known-bad commits, right? It won't mess up the next > selection of a test commit? I'm imagining someone jumping to a commit > between two known-bad commits or something, when it is more likely that > they are jumping to a parallel history. Until you run "git bisect bad" or "git bisect good" I don't think switching could mess up bisect. And I'm pretty sure I marked wrong ones once or twice and git-bisect did complain. It would be a good idea to warn about jumping in known-good-or-bad commit ranges. I'll keep this as an improvement point (there's still another one I haven't done, also about warning improvement, sigh). > > For this reason, allow to switch when bisecting (*). I considered if we > > should still prevent switching by default and allow it with > > --ignore-in-progress. But I don't think the prevention really adds > > anything much. > > > > If the user switches away by mistake, since we print the previous HEAD > > value, even if they don't know about the "-" shortcut, switching back is > > still possible. > > I tell everyone I know about the "-" shortcut, and I'm always surprised > they didn't already know about "cd -". I actually wanted to go a bit more aggressive/verbose about "teaching" users via the advice framework, but allows the user to turn off the "lessons" they already learned. Something like gcc adding [-Wno-foobar] in a warning to hint how to turn it off. I'll come back to this at some point, hopefully. -- Duy
