t7610-mergetool: use test_cmp instead of test $(cat file) = $txt

diff --git a/t/t6029-merge-subtree.sh b/t/t6029-merge-subtree.sh
index 7d5bc784721411a3abe475a8ed9f291204072b7d..793f0c8bf38aba350542c0710f509a1c69b33a9b 100755 (executable)
--- a/t/t6029-merge-subtree.sh
+++ b/t/t6029-merge-subtree.sh
@@ -29,6 +29,34 @@ test_expect_success 'subtree available and works like recursive' '
 
 '
 
+test_expect_success 'setup branch sub' '
+       git checkout --orphan sub &&
+       git rm -rf . &&
+       test_commit foo
+'
+
+test_expect_success 'setup branch main' '
+       git checkout -b main master &&
+       git merge -s ours --no-commit --allow-unrelated-histories sub &&
+       git read-tree --prefix=dir/ -u sub &&
+       git commit -m "initial merge of sub into main" &&
+       test_path_is_file dir/foo.t &&
+       test_path_is_file hello
+'
+
+test_expect_success 'update branch sub' '
+       git checkout sub &&
+       test_commit bar
+'
+
+test_expect_success 'update branch main' '
+       git checkout main &&
+       git merge -s subtree sub -m "second merge of sub into main" &&
+       test_path_is_file dir/bar.t &&
+       test_path_is_file dir/foo.t &&
+       test_path_is_file hello
+'
+
 test_expect_success 'setup' '
        mkdir git-gui &&
        cd git-gui &&