Verification of pokemon alive added

src/main/scala/backend/Pokemon/Pokemon.scala

@@ -39,5 +39,7 @@ trait Pokemon(
 
     def decreaseLife(x: Int): Unit = this._life = this.life - x
 
+    def isAlive: Boolean = !(this.life == 0)
+
     override def toString(): String =
         s"[${this.name}] Life: ${this.life}\nMaxLife: ${this.maxLife}\nAttack: ${this.attack}\nDefense: ${this.defense}\nSpeed: ${this.speed}\n"

src/main/scala/backend/Pokemon/Trainer.scala

@@ -8,4 +8,5 @@ class Trainer(val name: String, var listPokemon: List[Pokemon], var indexPrimary
 
     def changePrimaryPokemon(index: Int): Unit =
         assert(0 <= index && index < this.numberPokemon)
+        assert(this.listPokemon(index).isAlive)
         this.indexPrimaryPokemon = index