refactor(usb_handle): improve timestamp handling and code organization

- Move timestamp generation to start_process function
- Add timestamp to result string before creating status file
- Remove unnecessary blank lines
- Update test case to reflect new timestamp handling

sierra_status/src/usb_handle.py

@@ -59,7 +59,6 @@ def send_at_command(
                 if "OK\r\n" in result or "ERROR\r\n" in result:
                     break
                 animate_spinner()
-
     except serial.SerialException as e:
         logging.error(f"Serial communication error: {e}")
     except ValueError as e:
@@ -135,8 +134,6 @@ def creat_status_file(result: str, model: str) -> None:
     """
     try:
         time_stamp = time.strftime("%Y%m%d_%H%M%S", time.localtime())
-        result = f"Finished time: {time_stamp}\n" + result
-
         file_name = STATUS_FILE_PATTERN.format(model=model, timestamp=time_stamp)
         with open(file_name, "w") as f:
             f.write(result)
@@ -162,7 +159,6 @@ def start_process(
         None
     """
     start_time = time.time()
-
     logging.basicConfig(
         level=log_level, format="%(asctime)s - %(levelname)s - %(message)s"
     )
@@ -173,6 +169,8 @@ def start_process(
     )
     result = get_module_status(port, search, model, baudrate)
     if result:
+        time_stamp = time.strftime("%Y%m%d_%H%M%S", time.localtime())
+        result = f"Finished time: {time_stamp}\n" + result
         creat_status_file(result, model)
     else:
         logging.error("No result received from the module.")

tests/test_usb_handle.py

@@ -96,12 +96,15 @@ def test_creat_status_file(self, mock_strftime, mock_file) -> None:
 
     @patch("sierra_status.src.usb_handle.get_module_status")
     @patch("sierra_status.src.usb_handle.creat_status_file")
+    @patch("sierra_status.src.usb_handle.time.strftime")
     def test_start_process_with_result(
-        self, mock_creat_status_file, mock_get_module_status
+        self, mock_strftime, mock_creat_status_file, mock_get_module_status
     ) -> None:
         mock_get_module_status.return_value = "Test Status"
+        mock_strftime.return_value = "20230101_120000"
         start_process(self.mock_port, "TestModel", logging.INFO, 0)
-        mock_creat_status_file.assert_called_with("Test Status", "TestModel")
+        expected_result = "Finished time: 20230101_120000\nTest Status"
+        mock_creat_status_file.assert_called_with(expected_result, "TestModel")
 
     @patch("sierra_status.src.usb_handle.get_module_status")
     @patch("sierra_status.src.usb_handle.creat_status_file")