fix: Enhance argument handling in seed data script and add unit tests

tests/unit/test_seed_data.py

@@ -0,0 +1,46 @@
+import argparse
+from unittest import mock
+
+import scripts.seed_data as seed_data
+from scripts.seed_data import DatabaseConfig
+
+
+def test_run_with_namespace_handles_missing_theme_flag_without_actions() -> None:
+    args = argparse.Namespace(currencies=False, units=False, defaults=False)
+    config = mock.create_autospec(DatabaseConfig)
+    config.application_dsn.return_value = "postgresql://example"
+
+    with (
+        mock.patch("scripts.seed_data._configure_logging") as configure_logging,
+        mock.patch("scripts.seed_data.psycopg2.connect") as connect_mock,
+        mock.patch.object(seed_data.logger, "info") as info_mock,
+    ):
+        seed_data.run_with_namespace(args, config=config)
+
+    configure_logging.assert_called_once()
+    connect_mock.assert_not_called()
+    info_mock.assert_called_with("No seeding options provided; exiting")
+
+
+def test_run_with_namespace_seeds_defaults_without_theme_flag() -> None:
+    args = argparse.Namespace(
+        currencies=False, units=False, defaults=True, dry_run=False)
+    config = mock.create_autospec(DatabaseConfig)
+    config.application_dsn.return_value = "postgresql://example"
+
+    connection_mock = mock.MagicMock()
+    cursor_context = mock.MagicMock()
+    cursor_mock = mock.MagicMock()
+    connection_mock.__enter__.return_value = connection_mock
+    connection_mock.cursor.return_value = cursor_context
+    cursor_context.__enter__.return_value = cursor_mock
+
+    with (
+        mock.patch("scripts.seed_data._configure_logging"),
+        mock.patch("scripts.seed_data.psycopg2.connect", return_value=connection_mock) as connect_mock,
+        mock.patch("scripts.seed_data._seed_defaults") as seed_defaults,
+    ):
+        seed_data.run_with_namespace(args, config=config)
+
+    connect_mock.assert_called_once_with(config.application_dsn())
+    seed_defaults.assert_called_once_with(cursor_mock, dry_run=False)