Comment 4 for bug 1650215

After some investigation:

>>> import pkg_resources
>>> list(pkg_resources.iter_entry_points('tempest.test_plugins'))
[EntryPoint.parse('gnocchi_tests = gnocchi.tempest.plugin:GnocchiTempestPlugin'), EntryPoint.parse('aodh_tests = aodh.tests.tempest.plugin:AodhTempestPlugin'), EntryPoint.parse('neutron_tests = neutron.tests.tempest.plugin:NeutronTempestPlugin'), EntryPoint.parse('ceilometer_tests = ceilometer.tests.tempest.plugin:CeilometerTempestPlugin'), EntryPoint.parse('manila_tests = manila_tempest_tests.plugin:ManilaTempestPlugin'), EntryPoint.parse('cinder_tests = cinder.tests.tempest.plugin:CinderTempestPlugin'), EntryPoint.parse('keystone_tests = keystone_tempest_plugin.plugin:KeystoneTempestPlugin')]

But there are no catalogs:
       site-packages/aodh/tests
       site-packages/neutron/tests
       site-packages/cinder/tests
and so on.
These python packages are installed with a correspondent tempest entry point which is detected by pkg_resources package. But, actually, the tests itself are not installed as a part of its packages.