Add tests

Author: Anas Naouchi

omise/test/test_version.py

@@ -0,0 +1,13 @@
+import unittest
+from unittest import mock
+
+class VersionTest(unittest.TestCase):
+    @mock.patch("importlib.metadata.version", side_effect=__import__("importlib").metadata.PackageNotFoundError)
+    def test_version_package_not_found(self, mock_version):
+        """Ensure that PackageNotFoundError sets version to 'unknown'."""
+        from importlib import reload
+        import omise.version as omise_version
+
+        # Reload module so the import runs again and triggers our mock
+        reload(omise_version)
+        self.assertEqual(omise_version.__VERSION__, "unknown")