Re: Can I fetch an arbitrary commit by sha1?

> On Thu, Oct 2, 2014 at 12:10 PM, Jeff King <peff@peff.net> wrote:
>> On Thu, Oct 02, 2014 at 10:22:50AM -0400, Dan Johnson wrote:
>>> My understanding is that you are allowed to ask for a SHA1, but most
>>> git servers refuse the request. But if you already have the SHA
>>> locally, then git doesn't neet to bother asking the server for it, so
>>> there's no request to be refused.
>>
>> That's right. It is the server which enforces the "you cannot fetch an
>> arbitrary sha1" rule.
>>
>> But I think Christian is arguing that the client side should complain
>> that $sha1 is not a remote ref, and therefore not something we can
>> fetch.  This used to be the behavior until 6e7b66e (fetch: fetch objects
>> by their exact SHA-1 object names, 2013-01-29). The idea there is that
>> some refs may be kept "hidden" from the ref advertisement, but clients
>> who learn about the sha1 out-of-band may fetch the tips of hidden refs.
>>
>> I'm not sure it is a feature that has been particularly well-used to
>> date, though.
>
> There are efforts in the scientific communities at preserving
> experimental software and results. One of the things we'd like to do
> is shallow clone a specific sha1 commit