am -3: support 3way merge on unborn branch
While on an unborn branch, git am -3 will fail to do a threeway merge as
it references HEAD as "our tree", but HEAD does not point to a valid
tree.
Fix this by using an empty tree as "our tree" when we are on an unborn
branch.
Signed-off-by: Paul Tan <pyokagan@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/t/t4151-am-abort.sh b/t/t4151-am-abort.sh
index 5ac741a..2683ffa 100755
--- a/t/t4151-am-abort.sh
+++ b/t/t4151-am-abort.sh
@@ -83,4 +83,13 @@
test_cmp expect actual
'
+test_expect_success 'am -3 stops on conflict on unborn branch' '
+ git checkout -f --orphan orphan &&
+ git reset &&
+ rm -f otherfile-4 &&
+ test_must_fail git am -3 0003-*.patch &&
+ test 2 -eq $(git ls-files -u | wc -l) &&
+ test 4 = "$(cat otherfile-4)"
+'
+
test_done
