merge: refuse to create too cool a merge by default

diff --git a/t/t3033-merge-toplevel.sh b/t/t3033-merge-toplevel.sh
index 46aadc410bc470d9279ed1fd3ee72583d0963d30..c1379b00c2efc99a700c75f5ce13b2248706cf4b 100755 (executable)
--- a/t/t3033-merge-toplevel.sh
+++ b/t/t3033-merge-toplevel.sh
@@ -19,6 +19,8 @@ test_expect_success setup '
        test_commit three &&
        git checkout right &&
        test_commit four &&
+       git checkout --orphan five &&
+       test_commit five &&
        git checkout master
 '
 
@@ -133,4 +135,18 @@ test_expect_success 'merge FETCH_HEAD octopus non-fast-forward' '
        test_cmp expect actual
 '
 
+# two-project merge
+test_expect_success 'refuse two-project merge by default' '
+       t3033_reset &&
+       git reset --hard four &&
+       test_must_fail git merge five
+'
+
+test_expect_success 'two-project merge with --allow-unrelated-histories' '
+       t3033_reset &&
+       git reset --hard four &&
+       git merge --allow-unrelated-histories five &&
+       git diff --exit-code five
+'
+
 test_done