Fetching commit instead of ref

["Carlsson, Magnus" <Magnus.Carlsson@arris.com>]

Hi

I am involved in the git-subrepo project (https://github.com/ingydotnet/git-subrepo/). It's an attempt to simplify the inclusion of repos into other repos.

In a certain situation I would really need to fetch all commits related to a specific commit (SHA). I have read the git fetch documentation and found nothing regarding this. It only seems to support fetching references.

I found some traces on stack overflow:
https://stackoverflow.com/questions/14872486/retrieve-specific-commit-from-a-remote-git-repository

Following that recommendation it feels like it almost works:
$ git fetch subrepo 50f730db793e0733b159326c5a3e78fd48cedfec:refs/remote/subrepo/foo-commit
remote: Counting objects: 2311, done.
remote: Total 2311 (delta 0), reused 0 (delta 0), pack-reused 2311
Receiving objects: 100% (2311/2311), 703.64 KiB | 0 bytes/s, done.
Resolving deltas: 100% (1174/1174), done.
----> So far so good, but then an error message appear:
error: Server does not allow request for unadvertised object 50f730db793e0733b159326c5a3e78fd48cedfec
----> And nothing seems to be fetched.

Is there a way to fetch a commit and any ancestors to that commit based on a SHA?

Why do I need this?
In git-subrepo we try to recreate another repo within our main repo. Creating the necessary parent references when they appear. In some cases we need to make sure that we have access to the correct commits from the subrepo, but we don't have any references except a SHA.
 
-- Magnus
 
 
MAGNUS CARLSSON
 Staff Software Engineer
 ARRIS
 
 o: +46 13 36 75 92
 e: magnus.carlsson@arris.com
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