Local unittest runs does not use Neutron master

Tests py27, pep8 and py36 are executed against a stable version of Neutron locally and in the check/gate queue. Due to [2].

Only the docs job is run against master in the check/gate queue due to the zuul logic [1] (Need to double check that).

Ideally everything would run on Neutron master!

In the gate it could be achieved by adding statements like [1] for those other jobs as well.
Locally it's not yet clear to me. Change [3] required us to pin the Neutron version in requirements.txt. There is a mail thread that discusses this topic [4]. We also might check how other networking-* projects solve it...

[1] https://github.com/openstack-infra/project-config/blob/883565f7b736d129e252d08567131bb558d419d7/zuul.d/projects.yaml#L9388,L9389
[2] https://github.com/openstack/networking-dpm/blob/6efa84227ddb0d4cb89357398f0e5aae36517624/requirements.txt#L6
[3] https://github.com/openstack/networking-dpm/commit/2e59a8d34e0b682b0a8fa0490435b214008701bb
[4] http://lists.openstack.org/pipermail/openstack-dev/2018-April/129833.html