Add test for device metadata file creation and fixes until test passed.

code/tests/subcommands/test_add_device.py

@@ -0,0 +1,37 @@
+import sys
+import unittest
+from io import StringIO
+from unittest.mock import patch, MagicMock
+from pathlib import Path
+from iottb.definitions import DEVICE_METADATA_FILE
+import shutil
+from iottb.__main__ import main
+
+
+class TestDeviceSetup(unittest.TestCase):
+    def setUp(self):
+        self.test_dir = Path("/tmp/iottbtest/test_add_device")
+        self.test_dir.mkdir(parents=True, exist_ok=True)
+        # self.captured_output = StringIO()
+        # sys.stdout = self.captured_output
+
+    def tearDown(self):
+        # shutil.rmtree(str(self.test_dir))
+        for item in self.test_dir.iterdir():
+            if item.is_dir():
+                item.rmdir()
+            else:
+                item.unlink()
+        self.test_dir.rmdir()
+        # sys.stdout = sys.__stdout__
+
+    @patch("builtins.input", side_effect=["iPhone 14", "y", "y"])
+    def test_guided_device_setup(self, mock_input):
+        sys.argv = ['__main__.py', 'add', '--root_dir', str(self.test_dir), '--guided']
+        main()
+        expected_file = self.test_dir / DEVICE_METADATA_FILE
+        self.assertTrue(expected_file.exists()), f"Expected file not created: {expected_file}"
+
+
+if __name__ == '__main__':
+    unittest.main()