I noticed when creating a dev branch on Gather that Jenkins tests suddenly began failing. The errors suggested old code (PS1 - https://gerrit.wikimedia.org/r/#/c/247534/)
I noticed a dev branch existed on MobileFrontend and reading the logs it seemed to be used (10:32:03 DEBUG:zuul.Cloner:upstream repo has branch dev ). When deleting it and recreating it the tests magically passed.
My logic and reading of the Jenkins reports says that tests running on the dev branch of Gather were also running using the dev branch of MobileFrontend. If this is true that is awesome, but it's not documented anywhere. Could someone point me at some documentation if this is not true or clarify the situation if it is?