Re: [BUG] Cannot push some grafted branches

[Junio C Hamano <gitster@pobox.com>]

Michael J Gruber <git@drmicha.warpmail.net> writes:

> While replace refs are much more general than grafts, it seems the two
> main uses are:
>
> - grafts (change the recorded parents for a commit)
> - svn cleanup (convert tagging commits into tag objects)
>
> The latter one being quite a special case already.
>
> The script below has helped me move from grafts to replace objects.
> While not being super clean, something like it may be fit for contrib.
>
> I think we ought to help John Doe get along with parents, while we can
> safely leave most more advanced operations to people who know how to
> edit a raw object file. Putting that facility into "git-commit" seems to
> be too encouraging, though - people would use replace when they should
> use amend or rebase-i. I'd prefer a special git-replace mode (be it
> "--graft" or "--graft-commit") which does just what my script does. We
> could add things like "--commit-tag" later, a full blown
> "object-factory" seems like overkill.
>
> Michael
>
> --->%---
>
> #!/bin/sh
>
> die () {
> 	echo "$@"
> 	rm -f "$commitfile"
>  	exit 1
> }
>
> warn () {
> 	echo "$@"
> }
>
> test $# -gt 0 || die "Usage: $0 <commit> [<parent>]*"
>
> for commit
> do
> 	git rev-parse --verify -q "$commit" >/dev/null || die "Cannot parse
> $commit."
> 	test x$(git cat-file -t $commit) == "xcommit" || die "$commit is no
> commit."

s/==/=/ or you have to say #!/bin/bash on the first line, I think.
Appears multiple times throughout this script.


> done
>
> commit="$1"
> shift
>
> commitfile=$(mktemp)
>
> git cat-file commit "$commit" | while read a b
> do
> 	if test "$a" != "parent"
> 	then
> 		echo $a $b

You are losing information on non-header lines by reading without
"-r" in the above, and also multi-line headers (e.g. mergetag),
aren't you?

> 	fi
> 	if test "$a" == "tree"
> 	then
> 		for parent
> 		do
> 			echo "parent $(git rev-parse $parent)"
> 		done
> 	fi
> done >$commitfile
> hash=$(git hash-object -t commit -w "$commitfile") || die "Cannot create
> commit object."
> git replace "$commit" $hash
> rm -f $commitfile