Comment 3 for bug 1783751

Reviewed: https://review.openstack.org/586448
Committed: https://git.openstack.org/cgit/openstack/tempest/commit/?id=79159f80a9c0fec65637d498079e1b8958df8fb7
Submitter: Zuul
Branch: master

commit 79159f80a9c0fec65637d498079e1b8958df8fb7
Author: Masayuki Igawa <email address hidden>
Date: Fri Jul 27 15:00:37 2018 +0900

    Fix to enable `--config-file` option

    This commit sets the `--config-file` path to the environment variables
    `TEMPEST_CONFIG_DIR` and `TEMPEST_CONFIG` to enable the option as a
    workaround.
    The `path` is passed to `set_config_path()` however, the running test
    process is a child process which is a different instance.

    Change-Id: I8a65ee0f82e41f9659b3f40e2685c0ee0f290342
    Related-Bug: #1783751