Fixed falling blocks getting moved by currents, closes #2080

src/pocketmine/block/Liquid.php

@@ -189,11 +189,13 @@ abstract class Liquid extends Transparent{
 	}
 
 	public function addVelocityToEntity(Entity $entity, Vector3 $vector) : void{
+		if($entity->canBeMovedByCurrents()){
 			$flow = $this->getFlowVector();
 			$vector->x += $flow->x;
 			$vector->y += $flow->y;
 			$vector->z += $flow->z;
 		}
+	}
 
 	abstract public function tickRate() : int;
 

src/pocketmine/entity/Entity.php

@@ -1698,6 +1698,15 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		return $this->blocksAround;
 	}
 
+	/**
+	 * Returns whether this entity can be moved by currents in liquids.
+	 *
+	 * @return bool
+	 */
+	public function canBeMovedByCurrents() : bool{
+		return true;
+	}
+
 	protected function checkBlockCollision(){
 		$vector = new Vector3(0, 0, 0);
 

src/pocketmine/entity/object/FallingBlock.php

@@ -79,6 +79,10 @@ class FallingBlock extends Entity{
 		return false;
 	}
 
+	public function canBeMovedByCurrents() : bool{
+		return false;
+	}
+
 	public function attack(EntityDamageEvent $source){
 		if($source->getCause() === EntityDamageEvent::CAUSE_VOID){
 			parent::attack($source);