fix(Core/Units): Stop melee attacking victim if being charmed by non-friendly target. (#11353)

Fixes #11316

src/server/game/Entities/Unit/Unit.cpp

@@ -17896,6 +17896,8 @@ bool Unit::SetCharmedBy(Unit* charmer, CharmType type, AuraApplication const* au
     // Set charmed
     charmer->SetCharm(this, true);
 
+    StopAttackingInvalidTarget();
+
     if (GetTypeId() == TYPEID_UNIT)
     {
         if (MovementGenerator* movementGenerator = GetMotionMaster()->GetMotionSlot(MOTION_SLOT_IDLE))
@@ -18060,6 +18062,8 @@ void Unit::RemoveCharmedBy(Unit* charmer)
 
     charmer->SetCharm(this, false);
 
+    StopAttackingInvalidTarget();
+
     Player* playerCharmer = charmer->ToPlayer();
     if (playerCharmer)
     {
@@ -19591,6 +19595,37 @@ void Unit::StopAttackFaction(uint32 faction_id)
         (*itr)->StopAttackFaction(faction_id);
 }
 
+void Unit::StopAttackingInvalidTarget()
+{
+    AttackerSet const& attackers = getAttackers();
+    for (AttackerSet::const_iterator itr = attackers.begin(); itr != attackers.end();)
+    {
+        Unit* attacker = (*itr);
+        if (!attacker->IsValidAttackTarget(this))
+        {
+            attacker->AttackStop();
+            if (attacker->GetTypeId() == TYPEID_PLAYER)
+            {
+                attacker->ToPlayer()->SendAttackSwingCancelAttack();
+            }
+
+            for (Unit* controled : attacker->m_Controlled)
+            {
+                if (controled->GetVictim() == this && !controled->IsValidAttackTarget(this))
+                {
+                    controled->AttackStop();
+                }
+            }
+
+            itr = attackers.begin();
+        }
+        else
+        {
+            ++itr;
+        }
+    }
+}
+
 void Unit::OutDebugInfo() const
 {
     LOG_ERROR("entities.unit", "Unit::OutDebugInfo");

src/server/game/Entities/Unit/Unit.h

@@ -1360,6 +1360,7 @@ public:
     void CombatStop(bool includingCast = false);
     void CombatStopWithPets(bool includingCast = false);
     void StopAttackFaction(uint32 faction_id);
+    void StopAttackingInvalidTarget();
     Unit* SelectNearbyTarget(Unit* exclude = nullptr, float dist = NOMINAL_MELEE_RANGE) const;
     Unit* SelectNearbyNoTotemTarget(Unit* exclude = nullptr, float dist = NOMINAL_MELEE_RANGE) const;
     void SendMeleeAttackStop(Unit* victim = nullptr);