merge-octopus: abort if index does not match HEAD

diff --git a/t/t7600-merge.sh b/t/t7600-merge.sh
index 302e23826341bce6c3797330b5f2996877dc5baf..85248a14b61d68b61932d595eb0fa8fcaa8506b1 100755 (executable)
--- a/t/t7600-merge.sh
+++ b/t/t7600-merge.sh
@@ -33,9 +33,11 @@ printf '%s\n' 1 2 3 4 5 6 7 8 9 >file
 printf '%s\n' '1 X' 2 3 4 5 6 7 8 9 >file.1
 printf '%s\n' 1 2 3 4 '5 X' 6 7 8 9 >file.5
 printf '%s\n' 1 2 3 4 5 6 7 8 '9 X' >file.9
+printf '%s\n' 1 2 3 4 5 6 7 8 '9 Y' >file.9y
 printf '%s\n' '1 X' 2 3 4 5 6 7 8 9 >result.1
 printf '%s\n' '1 X' 2 3 4 '5 X' 6 7 8 9 >result.1-5
 printf '%s\n' '1 X' 2 3 4 '5 X' 6 7 8 '9 X' >result.1-5-9
+printf '%s\n' 1 2 3 4 5 6 7 8 '9 Z' >result.9z
 >empty
 
 create_merge_msgs () {
@@ -128,6 +130,12 @@ test_expect_success 'setup' '
        git tag c2 &&
        c2=$(git rev-parse HEAD) &&
        git reset --hard "$c0" &&
+       cp file.9y file &&
+       git add file &&
+       test_tick &&
+       git commit -m "commit 7" &&
+       git tag c7 &&
+       git reset --hard "$c0" &&
        cp file.9 file &&
        git add file &&
        test_tick &&
@@ -218,6 +226,26 @@ test_expect_success 'merge c1 with c2' '
        verify_parents $c1 $c2
 '
 
+test_expect_success 'merge --squash c3 with c7' '
+       git reset --hard c3 &&
+       test_must_fail git merge --squash c7 &&
+       cat result.9z >file &&
+       git commit --no-edit -a &&
+
+       {
+               cat <<-EOF
+               Squashed commit of the following:
+
+               $(git show -s c7)
+
+               # Conflicts:
+               #       file
+               EOF
+       } >expect &&
+       git cat-file commit HEAD | sed -e '1,/^$/d' >actual &&
+       test_cmp expect actual
+'
+
 test_debug 'git log --graph --decorate --oneline --all'
 
 test_expect_success 'merge c1 with c2 and c3' '
@@ -725,4 +753,14 @@ test_expect_success 'merge detects mod-256 conflicts (resolve)' '
        test_must_fail git merge -s resolve master
 '
 
+test_expect_success 'merge nothing into void' '
+       git init void &&
+       (
+               cd void &&
+               git remote add up .. &&
+               git fetch up &&
+               test_must_fail git merge FETCH_HEAD
+       )
+'
+
 test_done