check_serial_number
===================
**Source code:** `check_serial_number.py <https://chromium.googlesource.com/chromiumos/platform/factory/+/refs/heads/main/py/test/pytests/check_serial_number.py>`_

Checks if serial number is set correctly on a device.

Description
-----------
Some tests, for example, RF graphyte, assume DUTs have MLB serial number
available (in VPD and device data).  And the test will fail if a DUT
doesn't have MLB SN (e.g. it skipped previous station).

This test gets serial number from different sources and check if they are equal.

Test Procedure
--------------
This is an automated test.  It requires user interaction only if the test
failed, or if the "manual_check" flag is turned on.  This test will,

1. try to connect to device's state server
2. the device must have device_id
3. get SN from state server
4. get SN from VPD
5. these two SN must match

Dependency
----------

1. SSH connection (if we are checking remote device)
2. DUT is running factory software

Examples
--------
This test is already defined as "CheckSerialNumber"
in `generic_common.test_list.json` and "StationCheckSerialNumber" in
`station_based.test_list.json`. This test is turned on by default in station
based test list. You can disable it by setting `constants.check_serial_number`
to `false`::

  {
    "constants": {
      "check_serial_number": false
    }
  }

By default, this pytest checks mlb_serial_number. If you want to check serial
number instead::

  {
    "pytest_name": "check_serial_number",
    "args": {
      "sn_name": "serial_number"
    }
  }

By default, this pytest passes if the serial numbers match. If you want
additional manual confirmation (e.g. also match the serial number printed on
the device)::

  {
    "pytest_name": "check_serial_number",
    "args": {
      "manual_check": true
    }
  }



Test Arguments
--------------
.. list-table::
   :widths: 20 10 60
   :header-rows: 1
   :align: left

   * - Name
     - Type
     - Description

   * - sn_name
     - str
     - (optional; default: ``'mlb_serial_number'``) name of the serial number, e.g. "serial_number" or "mlb_serial_number"

   * - manual_check
     - bool
     - (optional; default: ``False``) If set to true, this test needs operator to press ENTER or ESC to pass or fail the test case.