In contracts, quasi-contracts, and quasi-delicts, the court may equitably mitigate the damages under circumstances other than the case referred to in the preceding article, as in the following instances:
(1) That the plaintiff himself has contravened the terms of the contract;
(2) That the plaintiff has derived some benefit as a result of the contract;
(3) In cases where exemplary damages are to be awarded, that the defendant acted upon the advice of counsel;
(4) That the loss would have resulted in any event;
(5) That since the filing of the action, the defendant has done his best to lessen the plaintiff's loss or injury.