Most ovsdbapp tests will be functional tests. Unit tests are reserved primarily for functions that produce a given output for their inputs, regardless of externalities. Unit tests using mock are acceptable if something is hard to test without it. BUT, please think carefully before writing a test that makes heavy use of mock.assert_called_once_with() as those tests very often tend to test what a function currently does and not what a function should do.
Tests are run with tox. Generally in the form of:
tox -e <test-type>
Run the functional tests with:
tox -e functional
The ovsdbapp functional tests create an OVS virtual environment similar to a Python virtualenv. OVS will be checked out from git and placed in .tox/functional/src/ovs and a virtual environment directory will be created. Various OVS servers will be launched and will store their runtime files in the virtual environment directory. The tests will then be run against these servers. Upon test completion, the servers will be killed and the virtual environment directory deleted. Note that one environment is created per test process, by default one per-core.
In the event that debugging tests is necessary, it is possible to keep the virtual environment directories by running:
KEEP_VENV=1 tox -e functional
This will also write an informational file .tox/functional/ovsvenv.$pid for each process. The first line of this file is the virtual environment directory and additional lines are the tests run by this process. To load an OVS virtualenv for debugging for a particular test (e.g. test_ls_add_name), call:
This will spawn a shell where you can run ovs-vsctl, ovn-nbctl, etc. on the db used by the test. When finished, type 'exit'. See the debug_venv help for more options.