diff --git a/t/t7800-difftool.sh b/t/t7800-difftool.sh
index 2418528487..5a193c500d 100755
--- a/t/t7800-difftool.sh
+++ b/t/t7800-difftool.sh
@@ -434,4 +434,18 @@ test_expect_success PERL 'difftool --no-symlinks detects conflict ' '
 	)
 '
 
+test_expect_success PERL 'difftool properly honors gitlink and core.worktree' '
+	git submodule add ./. submod/ule &&
+	(
+		cd submod/ule &&
+		test_config diff.tool checktrees &&
+		test_config difftool.checktrees.cmd '\''
+			test -d "$LOCAL" && test -d "$REMOTE" && echo good
+		'\'' &&
+		echo good >expect &&
+		git difftool --tool=checktrees --dir-diff HEAD~ >actual &&
+		test_cmp expect actual
+	)
+'
+
 test_done