echo hello > hello
echo world > world
BLOB1=$(git hash-object -w hello)
BLOB2=$(git hash-object -w world)
git add .
TREE=$(git write-tree)
COMMIT=$(git commit-tree $TREE -m "Initial commit")
git update-ref refs/a $BLOB1
git update-ref refs/b $BLOB2
git update-ref refs/c $TREE
git update-ref refs/d $COMMIT