Re: [PATCH] disable grafts during fetch/push/bundle

From: Jeff King <peff@peff.net>
Date: Mar 6, 2014, 15:56 UTC
Message-ID: <20140306155626.GB18519@sigill.intra.peff.net>
In-Reply-To: <53183506.5080002@alum.mit.edu>

On Thu, Mar 06, 2014 at 09:42:46AM +0100, Michael Haggerty wrote:

Show 7 quoted lines

> Replace objects are better than grafts in *almost* every dimension.  The
> exception is that it is dead simple to create grafts, whereas I always
> have to break open the man pages to remember how to create a replace
> object that does the same thing.
> 
> So I think a helpful step towards deprecating grafts would be to offer a
> couple of convenience features to help people kick the "grafts" habit:

I agree that better tool support would make "git replace" more pleasant to use.

> * A tool that converts grafts (i.e., the grafts read from
> $GIT_DIR/info/grafts) into the equivalent replacements.

I don't know if this is strictly necessary, if we make your command below pleasant to use. I.e., it should just be:

  while read sha1 parents; do
    git replace --graft $sha1 $parents
  done <.git/info/grafts

We can wrap that in "git replace --convert-grafts", but I do not think grafts are so common that there would be a big demand for it.

Show 8 quoted lines

> * A tool that creates a new replacement object that is the equivalent of
> a graft.  I.e., it should do, using replace references, the equivalent
> of the following command:
> 
>       echo SHA1 [PARENT1...] >>$GIT_DIR/info/grafts
> 
> These features could be added to "git replace" or could be built into a
> new "git grafts" command.

I think it would be nice to have a set of "mode" options for "git-replace" to do basic editing of a sha1 and install the result (technically you could split the editing into a separate command, but I do not see the point in editing a sha1 and then _not_ replacing it).

Perhaps:

  # pretty-print sha1 based on type, start $EDITOR, create a
  # type-appropriate object from the result (e.g., using hash-object,
  # mktree, or mktag), and then set up the object as a replacement for
  # SHA1
  git replace --edit SHA1

  # ditto, but replace the $EDITOR step with the parent list
  git replace --graft SHA1 PARENT1 PARENT2

  # ...or remove entries from a tree
  git replace --remove-entry SHA1 foo bar

-Peff