pocketmine\block\Grass::onActivate PHP Method

    public function onActivate(Item $item, Player $player = null)
    {
        if ($item->getId() === Item::DYE and $item->getDamage() === 0xf) {
            $item->count--;
            TallGrassObject::growGrass($this->getLevel(), $this, new Random(mt_rand()), 8, 2);
            return true;
        } elseif ($item->isHoe()) {
            $item->useOn($this);
            $this->getLevel()->setBlock($this, new Farmland());
            return true;
        } elseif ($item->isShovel() and $this->getSide(1)->getId() === Block::AIR) {
            $item->useOn($this);
            $this->getLevel()->setBlock($this, new GrassPath());
            return true;
        }
        return false;
    }