Commit 1bf6551e authored by Brandon Casey's avatar Brandon Casey Committed by Junio C Hamano support nearly proper tag name filtering

Add support for creating a new tag object and retaining the tag message,
author, and date when rewriting tags. The gpg signature, if one exists,
will be stripped.

This adds nearly proper tag name filtering to filter-branch. Proper tag
name filtering would include the ability to change the tagger, tag date,
tag message, and _not_ strip a gpg signature if the tag did not change.
Signed-off-by: default avatarBrandon Casey <>
Signed-off-by: default avatarJunio C Hamano <>
parent f58dbf23
......@@ -133,10 +133,16 @@ use "--tag-name-filter cat" to simply update the tags. In this
case, be very careful and make sure you have the old tags
backed up in case the conversion has run afoul.
Note that there is currently no support for proper rewriting of
tag objects; in layman terms, if the tag has a message or signature
attached, the rewritten tag won't have it. Sorry. (It is by
definition impossible to preserve signatures at any rate.)
Nearly proper rewriting of tag objects is supported. If the tag has
a message attached, a new tag object will be created with the same message,
author, and timestamp. If the tag has a signature attached, the
signature will be stripped. It is by definition impossible to preserve
signatures. The reason this is "nearly" proper, is because ideally if
the tag did not change (points to the same object, has the same name, etc.)
it should retain any signature. That is not the case, signatures will always
be removed, buyer beware. There is also no support for changing the
author or timestamp (or the tag message for that matter). Tags which point
to other tags will be rewritten to point to the underlying commit.
--subdirectory-filter <directory>::
Only look at the history which touches the given subdirectory.
......@@ -406,8 +406,22 @@ if [ "$filter_tag_name" ]; then
echo "$ref -> $new_ref ($sha1 -> $new_sha1)"
if [ "$type" = "tag" ]; then
# Warn that we are not rewriting the tag object itself.
warn "unreferencing tag object $sha1t"
new_sha1=$(git cat-file tag "$ref" |
sed -n \
-e "1,/^$/{
s/^object .*/object $new_sha1/
s/^type .*/type commit/
s/^tag .*/tag $new_ref/
}" \
-e '/^-----BEGIN PGP SIGNATURE-----/q' \
-e 'p' |
git mktag) ||
die "Could not create new tag object for $ref"
if git cat-file tag "$ref" | \
grep '^-----BEGIN PGP SIGNATURE-----' >/dev/null 2>&1
warn "gpg signature stripped from tag object $sha1t"
git update-ref "refs/tags/$new_ref" "$new_sha1" ||
......@@ -203,4 +203,36 @@ test_expect_success 'Subdirectory filter with disappearing trees' '
test $(git rev-list master | wc -l) = 3
test_expect_success 'Tag name filtering retains tag message' '
git tag -m atag T &&
git cat-file tag T > expect &&
git filter-branch -f --tag-name-filter cat &&
git cat-file tag T > actual &&
git diff expect actual
faux_gpg_tag='object XXXXXX
type commit
tag S
tagger T A Gger <> 1206026339 -0500
This is a faux gpg signed tag.
Version: FauxGPG v0.0.0 (FAUX/Linux)
test_expect_success 'Tag name filtering strips gpg signature' '
sha1=$(git rev-parse HEAD) &&
sha1t=$(echo "$faux_gpg_tag" | sed -e s/XXXXXX/$sha1/ | git mktag) &&
git update-ref "refs/tags/S" "$sha1t" &&
echo "$faux_gpg_tag" | sed -e s/XXXXXX/$sha1/ | head -n 6 > expect &&
git filter-branch -f --tag-name-filter cat &&
git cat-file tag S > actual &&
git diff expect actual
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment