WIP: Run standardised source tests from external plugins
Description
Adds some tooling to run the standardised source tests from external plugin repositories in the BuildStream test suite. This is all done in a tox environment to keep things clean. As external plugin repos could require a lot of config, including two refs to download (if we want a fixed version test and a master test), they are listed in a YAML file, which is parsed to generate two requirements files, and a list of package names. I'm not sure I like the way that the package names are passed into the tests, so feedback on that especially would be appreciated.
Changes proposed in this merge request:
- Remove hard test dependency on bst-plugins-experimental
- This needs some rework, as at the moment this has just broken integration tests which have moved
- Add external-requirements.yml and a parser to generate actual requirements files
- Add tox environments to run standardised source tests from any repo in
external-requirements.yml
- Run these against bst-plugins-experimental initially (bst-plugins-container has no standardised source tests, and is in the yaml file at the moment so I could test more than one repo ran properly)
Implementing part of https://mail.gnome.org/archives/buildstream-list/2019-August/msg00017.html
Edited by Tom Coldrick