Re: [ANNOUNCE] GIT 1.5.5.1

[Brandon Casey <casey@nrlssc.navy.mil>]

Dmitry Potapov wrote:
> On Mon, Apr 21, 2008 at 07:23:10PM -0500, Brandon Casey wrote:
>> Dmitry Potapov wrote:
>>
>>> Johannes' patch removed this option, which IMHO was a significant user
>>> interface improvement.
>> Unless I missed something, this option has not been removed. The original
>> purpose for its existence (which was to cause git-gc to call git-prune)
>> has been removed. The call to git-prune within git-gc will remove _loose_
>> unreferenced objects, but _packed_ unreferenced objects are removed by
>> repack. The --prune option to git-gc is still used to adjust the call to
>> git-repack so that packed unreferenced objects are discarded.
> 
> I thought that it had no effect any more, because it had been removed
> from the git-gc man page. Now I have looked at the code now, and it seems
> the difference between running git gc with and without the prune option
> is that with this option the git repack is called with '-a' option while
> without it with '-A'. Unfortunately, the '-A' option in the git-repack
> is also undocumented, but based on the reading git-repack.sh, you are
> right. So, now I wonder wether removing the --prune option from the man
> page was the right thing to do.
> 
>>> diff --git a/Documentation/git-clone.txt b/Documentation/git-clone.txt
>>> index 9758243..c1bf814 100644
>>> --- a/Documentation/git-clone.txt
>>> +++ b/Documentation/git-clone.txt
>>> @@ -65,10 +65,12 @@ OPTIONS
>>>  +
>>>  *NOTE*: this is a possibly dangerous operation; do *not* use
>>>  it unless you understand what it does. If you clone your
>>> -repository using this option, then delete branches in the
>>> -source repository and then run linkgit:git-gc[1] using the
>>> -'--prune' option in the source repository, it may remove
>>> -objects which are referenced by the cloned repository.
>>> +repository using this option and then delete a branch or use
>>> +any other git command that makes any previous existing commit
>>> +unreachable, then after some time linkgit:git-gc[1] may remove
>>> +unreachable objects, and this will break the cloned repository.
>>> +Because some git commands may run git-gc, it may happen at any
>>> +time after gc.pruneExpire time since commits became unreachable.
>> I agree that something should be said here about shared repositories,
>> but I think this wording is a little complicated (disclosure: I also
>> submitted some text for this a few weeks ago :). Of course something
>> is better than nothing.
>>
>> Here's the blurb I submitted if you're interested:
>> +repository using this option and then delete branches in the
>> +source repository, some objects may become unreferenced (or dangling).
>> +These objects may be removed by normal git operations (such as git-commit[1])
>> +which automatically call git-gc[1]. If these objects are removed and
>> +were referenced by the cloned repository, then the cloned repository
>> +will become corrupt.
> 
> I like your wording better though I still prefer to mention that
> deleting branches is just one of many possible commands that may
> create unreferenced commits, i.e. something like that:
> 
>  ... repository using this option and then delete branches (or use any
>  other git command that makes any existing commit unreferenced) ...

That's fine, but one of us needs to resubmit. Care to do the honors? :)

-brandon