[PATCH] scripts: git-resolve: ignore non-commit objects

[Hamdy Abou El Anein]

From: Hamdy Abou El Anein <hamdy.aea@xxxxxxxxxxxxxx>

git rev-parse --disambiguate lists objects of every type. A unique blob
or tree prefix is therefore returned successfully as a commit ID. Such
an ID cannot be used as a commit reference or Fixes tag.

Filter the candidates by object type before deciding whether the prefix
is unique or looking up its subject.

Tested in a temporary Git repository: a real commit prefix resolves to
its full ID, while a stored blob prefix is rejected with no output.

AI assistance: ChatGPT/Codex identified the issue and prepared the
change, commit message and executable regression tests.

Fixes: 7ae52a3d7f51 ("scripts: Add git-resolve tool for full SHA-1 resolution")
Signed-off-by: Hamdy Abou El Anein <hamdy.aea@xxxxxxxxxxxxxx>
---
 scripts/git-resolve.sh | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/scripts/git-resolve.sh b/scripts/git-resolve.sh
index e9b5940c0f2..0be8838cd13 100755
--- a/scripts/git-resolve.sh
+++ b/scripts/git-resolve.sh
@@ -49,7 +49,9 @@ git_resolve_commit() {
 
 	# Get all possible matching commit IDs
 	local matches
-	readarray -t matches < <(git rev-parse --disambiguate="$commit_id" 2>/dev/null)
+	readarray -t matches < <(git rev-parse --disambiguate="$commit_id" 2>/dev/null |
+		git cat-file --batch-check='%(objectname) %(objecttype)' |
+		awk '$2 == "commit" { print $1 }')
 
 	# Return immediately if we have exactly one match
 	if [ ${#matches[@]} -eq 1 ]; then