Take a look here.
This function has been used to settle adjustments in protocol. The main issue about this report is the fact that adding/removing the share is dependent on if the adjustment is positive or not. This is a somewhat flawed implementation, as the is_positive() getter would actually return false for when adjustment == 0 and as such lead to an unnecessary attempt of removing 0 shares.
Not enough input validation is applied, not the best code structure.
Consider checking in the function to ensure that for instances where adjustment == 0 none of neither add_shares() or remove_shares() is called.
