pocketmine\inventory\BaseTransaction::execute PHP Method

    public function execute(Player $source) : bool
    {
        if ($this->getInventory()->processSlotChange($this)) {
            //This means that the transaction should be handled the normal way
            if (!$source->getServer()->allowInventoryCheats and !$source->isCreative()) {
                $change = $this->getChange();
                if ($change === null) {
                    //No changes to make, ignore this transaction
                    return true;
                }
                /* Verify that we have the required items */
                if ($change["out"] instanceof Item) {
                    if (!$this->getInventory()->slotContains($this->getSlot(), $change["out"])) {
                        return false;
                    }
                }
                if ($change["in"] instanceof Item) {
                    if (!$source->getFloatingInventory()->contains($change["in"])) {
                        return false;
                    }
                }
                /* All checks passed, make changes to floating inventory
                 * This will not be reached unless all requirements are met */
                if ($change["out"] instanceof Item) {
                    $source->getFloatingInventory()->addItem($change["out"]);
                }
                if ($change["in"] instanceof Item) {
                    $source->getFloatingInventory()->removeItem($change["in"]);
                }
            }
            $this->getInventory()->setItem($this->getSlot(), $this->getTargetItem(), false);
        }
        /* Process transaction achievements, like getting iron from a furnace */
        foreach ($this->achievements as $achievement) {
            $source->awardAchievement($achievement);
        }
        return true;
    }