subtree: fix split after annotated tag was squashed merged

The previous commit fixed a failure in 'git subtree merge --squash' when
the previous squash-merge merged an annotated tag of the subtree
repository which is missing locally.

The same failure happens in 'git subtree split', either directly or when
called by 'git subtree push', under the same circumstances: 'cmd_split'
invokes 'find_existing_splits', which loops through previous commits and
invokes 'git rev-parse' (via 'process_subtree_split_trailer') on the
value of any 'git subtree-split' trailer it finds. This fails if this
value is the hash of an annotated tag which is missing locally.

Add a new optional argument 'repository' to 'cmd_split' and
'find_existing_splits', and invoke 'cmd_split' with that argument from
'cmd_push'. This allows 'process_subtree_split_trailer' to try to fetch
the missing tag from the 'repository' if it's not available locally,
mirroring the new behaviour of 'git subtree pull' and 'git subtree
merge'.

Signed-off-by: Philippe Blain <levraiphilippeblain@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 18 insertions, 8 deletions

diff --git a/contrib/subtree/git-subtree.sh b/contrib/subtree/git-subtree.sh
index 2c67989fe8..10c9c87839 100755
--- a/contrib/subtree/git-subtree.sh
+++ b/contrib/subtree/git-subtree.sh
@@ -453,14 +453,19 @@ find_latest_squash () {
 	done || exit $?
 }
 
-# Usage: find_existing_splits DIR REV
+# Usage: find_existing_splits DIR REV [REPOSITORY]
 find_existing_splits () {
-	assert test $# = 2
+	assert test $# = 2 -o $# = 3
 	debug "Looking for prior splits..."
 	local indent=$(($indent + 1))
 
 	dir="$1"
 	rev="$2"
+	repository=""
+	if test "$#" = 3
+	then
+		repository="$3"
+	fi
 	main=
 	sub=
 	local grep_format="^git-subtree-dir: $dir/*\$"
@@ -480,7 +485,7 @@ find_existing_splits () {
 			main="$b"
 			;;
 		git-subtree-split:)
-			process_subtree_split_trailer "$b" "$sq"
+			process_subtree_split_trailer "$b" "$sq" "$repository"
 			;;
 		END)
 			debug "Main is: '$main'"
@@ -906,17 +911,22 @@ cmd_add_commit () {
 	say >&2 "Added dir '$dir'"
 }
 
-# Usage: cmd_split [REV]
+# Usage: cmd_split [REV] [REPOSITORY]
 cmd_split () {
 	if test $# -eq 0
 	then
 		rev=$(git rev-parse HEAD)
-	elif test $# -eq 1
+	elif test $# -eq 1 -o $# -eq 2
 	then
 		rev=$(git rev-parse -q --verify "$1^{commit}") ||
 			die "fatal: '$1' does not refer to a commit"
 	else
-		die "fatal: you must provide exactly one revision.  Got: '$*'"
+		die "fatal: you must provide exactly one revision, and optionnally a repository.  Got: '$*'"
+	fi
+	repository=""
+	if test "$#" = 2
+	then
+		repository="$2"
 	fi
 
 	if test -n "$arg_split_rejoin"
@@ -940,7 +950,7 @@ cmd_split () {
 		done || exit $?
 	fi
 
-	unrevs="$(find_existing_splits "$dir" "$rev")" || exit $?
+	unrevs="$(find_existing_splits "$dir" "$rev" "$repository")" || exit $?
 
 	# We can't restrict rev-list to only $dir here, because some of our
 	# parents have the $dir contents the root, and those won't match.
@@ -1072,7 +1082,7 @@ cmd_push () {
 			die "fatal: '$localrevname_presplit' does not refer to a commit"
 
 		echo "git push using: " "$repository" "$refspec"
-		localrev=$(cmd_split "$localrev_presplit") || die
+		localrev=$(cmd_split "$localrev_presplit" "$repository") || die
 		git push "$repository" "$localrev":"refs/heads/$remoteref"
 	else
 		die "fatal: '$dir' must already exist. Try 'git subtree add'."