.. _tests-unit-test-charm-py-file:


``tests/unit/test_charm.py`` file
=================================

    See also: `How to write unit tests for a charm
    <https://juju.is/docs/sdk/write-a-unit-test-for-a-charm>`_

The ``tests/unit/test_charm.py`` file is the companion to
``src/charm.py`` for unit testing. It is pre-populated with standard
constructs used by ``unittest`` and Harness.

This file is created automatically by ``charmcraft init`` and it is
pre-populated with standard constructs used by ``unittest`` and
``Harness``, along the lines below:

.. code-block:: python

    # Copyright 2023 Ubuntu
    # See LICENSE file for licensing details.
    #
    # Learn more about testing at: https://juju.is/docs/sdk/testing

    import unittest

    import ops
    import ops.testing
    from charm import MyK8SCharmCharm


    class TestCharm(unittest.TestCase):
        def setUp(self):
            self.harness = ops.testing.Harness(MyK8SCharmCharm)
            self.addCleanup(self.harness.cleanup)
            self.harness.begin()

        def test_pebble_ready(self):
            # Simulate the container coming up and emission of pebble-ready event
            self.harness.container_pebble_ready("some-container")
            # Ensure we set an ActiveStatus with no message
            self.assertEqual(self.harness.model.unit.status, ops.ActiveStatus())