Define Branch Creation Requirements

[jhpierce]

Design Challenge

Where are branch names defined? Is it ok if they already exist? Users must have custom branch names, so where will they specify those branch names?

Requirements

• Branches must be known at the pre-processing phase for async and sync code modifications.
• They must be unlikely to collide with existing branches
• They must be deterministically built from the changeset, so that given a changeset you know exactly which branch it would create PRs on. This way, we can look up existing branches and decide to short-circuit or not in pre-processing based on commit history