isSet(cardA, cardB, cardC) { return ( this.validateProps(cardA.shape, cardB.shape, cardC.shape) && this.validateProps(cardA.amount, cardB.amount, cardC.amount) && this.validateProps(cardA.filling, cardB.filling, cardC.filling) && this.validateProps(cardA.color, cardB.color, cardC.color) ); }