A benefit of git is that we use ad-hoc branches, and the default for the Git plugin is that all branches get built.

That's great, but we'd really like to be able to extract 'master' from the build, and have the ad-hoc branches built as part of another build.

That means that we need to be able to write a branch spec of master for one (okay... that works), and !master for the other.

I've looked at BranchSpec, and we don't have the option to use regexp.Pattern expressions because everything is escaped with Pattern.quote(), so it seems the simplest approach would be to have a flag to invert the pattern, e.g. !