Re: git-bisect reset not deleting .git/BISECT_LOG

From: Jeff King <peff@peff.net>
Date: Nov 13, 2023, 21:08 UTC
Message-ID: <20231113210820.GB2028092@coredump.intra.peff.net>
In-Reply-To: <bef9d5b3-bb64-4662-8952-d000872c5244@aq0.de>

On Mon, Nov 13, 2023 at 09:42:09PM +0100, Janik Haag wrote:

Show 19 quoted lines

> Thank you for filling out a Git bug report!
> Please answer the following questions to help us understand your issue.
> 
> What did you do before the bug happened? (Steps to reproduce your issue)
> ```bash
> git init /tmp/reproduce-bisect-warning
> cd /tmp/reproduce-bisect-warning
> touch .git/BISECT_LOG
> git bisect reset
> git switch -c log
> ```
> 
> What did you expect to happen? (Expected behavior)
> 
> `git-bisect reset` should have deleted .git/BISECT_LOG
> 
> What happened instead? (Actual behavior)
> 
> .git/BISECT_LOG is still there

I don't think this is really specific to BISECT_LOG. In "bisect reset", we'll call bisect_clean_state(), which removes a bunch of files. The problem in your example is that "bisect reset" sees that we are not bisecting and bails early.

Which I can kind of see, as part of the "reset" process is to reset to the original pre-bisect commit. If it's not given on the command line, the default is to use BISECT_START, which of course does not exist.

  As a side note, "git bisect reset HEAD" will do what you want, because
  it skips the BISECT_START check. But obviously that's not something
  normal users should need to know about, and I think is even an
  accidental side-effect of the conversion in 5e82c3dd22
  (bisect--helper: `bisect_reset` shell function in C, 2019-01-02).

So really, you just want the "clean" part of "bisect reset", but not the "reset". We could have a separate "bisect clean" that would do what you want (clean state without trying to reset HEAD). But I don't think it would be unreasonable to "reset" to just unconditionally clean. I think it would probably just be a few lines in bisect_reset() to avoid the early return, and skip the call to "checkout" when we have no branch to go back to.

Maybe a good simple patch for somebody interested in getting into Git development?

-Peff