So if somebody can come up with an expression parser for the old configuration string that can reliably distinguish between:
- PR-* means build all branches whos names begin with PR- such as PR-foobar and do not build pull requests because our SCMSource doesn't even have the concept.
- PR-* means build all pull-requests but we don't want to accidentally build branches with names that begin with PR- because we just want to build the master branch.
- CR-* means build all pull-requests because our SCMSource calls them Change Requests and uses CR- as the prefix
I would be happy to merge.
Until then, the least risk (given that building a branch can result in deploying things into production or expose secrets to a build that isn't trusted) is to err on the side of "if we don't know, do nothing".
In any case, we could argue that the old `Automatic branch project triggering` has a bug of requiring you to know to add PR-* in order to build pull requests... just that people were relying on the bug!