grep "HEAD points to something strange" out
'
+test_expect_success 'HEAD link pointing at a funny object (from different wt)' '
+ test_when_finished "mv .git/SAVED_HEAD .git/HEAD" &&
+ test_when_finished "rm -rf .git/worktrees wt" &&
+ git worktree add wt &&
+ mv .git/HEAD .git/SAVED_HEAD &&
+ echo $ZERO_OID >.git/HEAD &&
+ # avoid corrupt/broken HEAD from interfering with repo discovery
+ test_must_fail git -C wt fsck 2>out &&
+ grep "main-worktree/HEAD: detached HEAD points" out
+'
+
+test_expect_success 'other worktree HEAD link pointing at a funny object' '
+ test_when_finished "rm -rf .git/worktrees other" &&
+ git worktree add other &&
+ echo $ZERO_OID >.git/worktrees/other/HEAD &&
+ test_must_fail git fsck 2>out &&
+ grep "worktrees/other/HEAD: detached HEAD points" out
+'
+
+test_expect_success 'other worktree HEAD link pointing at missing object' '
+ test_when_finished "rm -rf .git/worktrees other" &&
+ git worktree add other &&
+ echo "Contents missing from repo" | git hash-object --stdin >.git/worktrees/other/HEAD &&
+ test_must_fail git fsck 2>out &&
+ grep "worktrees/other/HEAD: invalid sha1 pointer" out
+'
+
+test_expect_success 'other worktree HEAD link pointing at a funny place' '
+ test_when_finished "rm -rf .git/worktrees other" &&
+ git worktree add other &&
+ echo "ref: refs/funny/place" >.git/worktrees/other/HEAD &&
+ test_must_fail git fsck 2>out &&
+ grep "worktrees/other/HEAD points to something strange" out
+'
+
test_expect_success 'email without @ is okay' '
git cat-file commit HEAD >basis &&
sed "s/@/AT/" basis >okay &&