From 1d5978df9804f56545ad2b3815ce98bf08abe0bc Mon Sep 17 00:00:00 2001
From: "Dylan K. Taylor" <odigiman@gmail.com>
Date: Fri, 30 Mar 2018 12:20:59 +0100
Subject: [PATCH] Fixed falling blocks getting moved by currents, closes #2080

---
 src/pocketmine/block/Liquid.php               | 10 ++++++----
 src/pocketmine/entity/Entity.php              |  9 +++++++++
 src/pocketmine/entity/object/FallingBlock.php |  4 ++++
 3 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/src/pocketmine/block/Liquid.php b/src/pocketmine/block/Liquid.php
index 9d78a746e..16cfc1633 100644
--- a/src/pocketmine/block/Liquid.php
+++ b/src/pocketmine/block/Liquid.php
@@ -189,10 +189,12 @@ abstract class Liquid extends Transparent{
 	}
 
 	public function addVelocityToEntity(Entity $entity, Vector3 $vector) : void{
-		$flow = $this->getFlowVector();
-		$vector->x += $flow->x;
-		$vector->y += $flow->y;
-		$vector->z += $flow->z;
+		if($entity->canBeMovedByCurrents()){
+			$flow = $this->getFlowVector();
+			$vector->x += $flow->x;
+			$vector->y += $flow->y;
+			$vector->z += $flow->z;
+		}
 	}
 
 	abstract public function tickRate() : int;
diff --git a/src/pocketmine/entity/Entity.php b/src/pocketmine/entity/Entity.php
index cfec599be..8239c7d34 100644
--- a/src/pocketmine/entity/Entity.php
+++ b/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);
 
diff --git a/src/pocketmine/entity/object/FallingBlock.php b/src/pocketmine/entity/object/FallingBlock.php
index 982c63ab5..44a7a55d3 100644
--- a/src/pocketmine/entity/object/FallingBlock.php
+++ b/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);