Re: rfe: bisecting with a tristate

From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Jul 24, 2007, 13:52 UTC
Message-ID: <Pine.LNX.4.64.0707241447200.14781@racer.site>
In-Reply-To: <20070724094017.d14688e5.seanlkml@sympatico.ca>

Hi,

On Tue, 24 Jul 2007, Sean wrote:

Show 14 quoted lines

> > git bisect start
> > git bisect bad v2.6.23-rc1
> > # bad: [f695baf2df9e0413d3521661070103711545207a] Linux 2.6.23-rc1
> > git bisect good v2.6.22
> > # good: [098fd16f00005f665d3baa7e682d8cb3d7c0fe6f] Linux 2.6.22
> > 
> > Then 1f1c2881f673671539b25686df463518d69c4649 will be the next commit 
> > git bisect hands out. Now let's assume this commit would not compile. 
> > What would the user do? git-bisect good or git-bisect bad?
> 
> Check out the section "Avoiding to test a commit" in the git-bisect
> man page; it addresses this issue.  Basically you just use git-reset
> to pick a different nearby commit to compile, and then continue with
> git bisect good/bad.

But a "git bisect dunno" would be handy.

However, it is a bit involved, since git-bisect.sh assumes that there is only one bad commit, and with that, the outcome would be possibly a commit range.

Two parts to it I see:

- builtin-rev-list.c:find_bisection() has to be told to ignore the dunno 
  commits when counting, in addition to uninteresting ones (but not stop 
  traversal). The easiest way I could see would be to add another option 
  to specify the dunno commits, and set a special flag on these.

- git-bisect.sh has to lose the assumption that there is only one bad 
  commit.  Instead, it has to traverse the parent(s) of "the" bad commit, 
  until it finds either no parents, or a known good one.  So maybe 
  something like

	echo $(git rev-list --boundary $bad --not $good |
		sed -n "s/^-/^/p") $bad

  would be enough.

Hth, Dscho