Re: [PATCH 0/2] fix "rebase -i --root" corrupting root commit

From: Phillip Wood <phillip.wood@talktalk.net>
Date: Jul 30, 2018, 12:14 UTC
Message-ID: <1f172fc1-4b51-cdf7-e841-5ca41e209be4@talktalk.net>
In-Reply-To: <20180730092929.71114-1-sunshine@sunshineco.com>

On 30/07/18 10:29, Eric Sunshine wrote:

Show 26 quoted lines

> This series fixes bugs causing corruption of the root commit when
> "rebase -i --root" is used to swap in a new root commit. In particular,
> the "author" header has trailing garbage. Some tools handle the
> corruption somewhat gracefully by showing a bogus date, but others barf
> on it (gitk, for instance). git-fsck correctly identifies the
> corruption. I discovered this after git-rebase corrupted one of my own
> projects.
> 
> Unfortunately, these bugs (from js/sequencer-and-root-commits) made it
> into the v2.18.0 release. It's worrying that a released Git can be
> creating corrupt commits, but fortunately "rebase -i --root" is not
> likely used often (especially on well-established projects).
> Nevertheless, it may be 'maint' worthy and applies cleanly there.
> 
> It was only after I diagnosed and fixed these bugs that I thought to
> check 'pu' and discovered that Akinori MUSHA already made a stab[1] at
> fixing one of the three bugs which this series fixes. Akinori's fix has
> the somewhat undesirable property that it adds an extra blank line to
> the end of the script, as Phillip correctly pointed out in review[2].
> Patch 2/2 of this series has the more "correct" fix, in addition to
> fixing another bug.
> 
> Moreover, patch 2/2 of this series provides a more thorough fix overall
> than Akinori, so it may make sense to replace his patch with this
> series, though perhaps keep the test his patch adds to augment the
> strict test of the "author" header added by this series.

Johannes and I have some fixups for Akinori's patch on the branch fix-t3403-author-script-test at https://github.com/phillipwood/git

That branch also contains a fix for the bad quoting of names with "'" in them. I think it would be good to somehow try and combine this series with those patches.

I'd really like to see a single function to read and another to write the author script that is shared by 'git am' and 'git rebase -i', rather than the two writers and three readers we have at the moment. I was thinking of doing that in the longer term, but given the extra bug you've found in read_author_script() maybe we should do that sooner rather than later.

Show 11 quoted lines

> [1]: https://public-inbox.org/git/86a7qwpt9g.knu@iDaemons.org/
> [2]: https://public-inbox.org/git/f5b56540-d26a-044e-5f46-1d975f889d06@talktalk.net/
> 
> Eric Sunshine (2):
>   sequencer: fix "rebase -i --root" corrupting author header
>   sequencer: fix "rebase -i --root" corrupting author header timezone
> 
>  sequencer.c                   |  9 +++++++--
>  t/t3404-rebase-interactive.sh | 10 +++++++++-
>  2 files changed, 16 insertions(+), 3 deletions(-)
>