diff --git a/unit_test/main_tests/main_options_test.py b/unit_test/main_tests/main_options_test.py
index b0422589..c7e6bfdd 100644
--- a/unit_test/main_tests/main_options_test.py
+++ b/unit_test/main_tests/main_options_test.py
@@ -235,7 +235,7 @@ def test_build_selector_migrations(intercepted_build_args, monkeypatch, option_n
         assert intercepted_build_selector.skip_patterns == build_selector_patterns
 
 
-@pytest.mark.parametrize('before_all', [None, 'test text'])
+@pytest.mark.parametrize('before_all', ["", None, 'test text'])
 @pytest.mark.parametrize('platform_specific', [False, True])
 def test_before_all(before_all, platform_specific, platform, intercepted_build_args, monkeypatch):
     if before_all is not None:
@@ -247,4 +247,7 @@ def test_before_all(before_all, platform_specific, platform, intercepted_build_a
 
     main()
 
+    if before_all is None:
+        before_all = ""
+
     assert intercepted_build_args.args[0].before_all == before_all