Re: commit gone after merge - how to debug?

From: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
Date: Nov 26, 2012, 13:38 UTC
Message-ID: <vpqehjgscv3.fsf@grenoble-inp.fr>
In-Reply-To: <CAO1Khk9mzJjnysnc1iDFeMgqnRq0z35t0kgC-8nrsjJ-oOvdOg@mail.gmail.com>

Igor Lautar <igor.lautar@gmail.com> writes:

Show 7 quoted lines

> On Mon, Nov 26, 2012 at 2:23 PM, Matthieu Moy
> <Matthieu.Moy@grenoble-inp.fr> wrote:
>> The other related question being: does reading the section "History
>> Simplification" in "man git-log" help? ;-)
>
> Somewhat, but it does not explain why the file no longer has that
> change.

It still has, but it's not shown by "git log <file>", probably because one of the parent of the merge commit introduces no change for this file, so one side of the merge is not needed to explain you how you went from the origin of time to the last commit.

Try this:

commit=<sha1 of your merge commit> # Show diff with first parent: git diff "$commit" "$commit"^1 # Show diff with second parent: git diff "$commit" "$commit"^2

> I can understand omitting history if end result is the same, but here
> it shouldn't be - I cannot find a commit that reversed that change, so
> the change should still be in after the merge?

revert is not the only situation that can lead to history simplification. I'm no expert in the domain, but I think if you did the same change in two branches, the merge will be candidate for history simplification.

-- 
Matthieu Moy
http://www-verimag.imag.fr/~moy/