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Date:   Wed, 14 Jun 2017 05:24:54 -0400
From:   Jeff King <peff@peff.net>
To:     Michael Haggerty <mhagger@alum.mit.edu>
Cc:     Junio C Hamano <gitster@pobox.com>,
        =?utf-8?B?Tmd1eeG7hW4gVGjDoWkgTmfhu41j?= Duy <pclouds@gmail.com>,
        Stefan Beller <sbeller@google.com>,
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        David Turner <novalis@novalis.org>,
        Brandon Williams <bmwill@google.com>,
        Johannes Sixt <j6t@kdbg.org>,
        =?utf-8?Q?=C3=98yvind?= Holm <sunny@sunbase.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        git@vger.kernel.org
Subject: Re: [PATCH 0/2] Fix a refname trimming problem in `log --bisect`
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On Wed, Jun 14, 2017 at 11:07:25AM +0200, Michael Haggerty wrote:

> Fix the problem in two orthogonal ways:
> 
> 1. Add a new function, `for_each_fullref_in_submodule()`, that doesn't
>    trim the refnames that it passes to callbacks, and us that instead.
>    I *think* that this is a strict improvement, though I don't know
>    the `git log` code well enough to be sure that it won't have bad
>    side-effects.

I think this is fine, for the reasons I gave elsewhere in the thread.

> 2. Relax the "trimming too many characters" check to allow the full
>    length of the refname to be trimmed away (though not more than
>    that).
> 
> In an ideal world the second patch shouldn't be necessary, because
> this calling pattern is questionable and it might be better that we
> learn about any other offenders. But if we'd rather be conservative
> and not break any other code that might rely on the old behavior,
> patch 2 is my suggestion for how to do it.

My preference would be to hold off on (2) if we can avoid it. It's
cleaner, and I think flushing out these kinds of bugs is useful.

-Peff