Core/Auras:

- Use safer order of calls in AuraEffect handlers (unit modification goes before any calls which may result in linked events execution)
 - Allow manual removal of further effects of an aura during aura removal (so Unit::RemoveAurasByType works well in such situations)

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

@@ -3277,6 +3277,7 @@ void Unit::_UnapplyAura(AuraApplicationMap::iterator &i, AuraRemoveMode removeMo
     ASSERT(aurApp);
     ASSERT(!aurApp->GetRemoveMode());
     ASSERT(aurApp->GetTarget() == this);
+  
     aurApp->SetRemoveMode(removeMode);
     Aura * aura = aurApp->GetBase();
     sLog->outDebug(LOG_FILTER_SPELLS_AURAS, "Aura %u now is remove mode %d", aura->GetId(), removeMode);
@@ -3573,9 +3574,22 @@ void Unit::RemoveAura(uint32 spellId, uint64 caster, uint8 reqEffMask, AuraRemov
 
 void Unit::RemoveAura(AuraApplication * aurApp, AuraRemoveMode mode)
 {
-    ASSERT(aurApp->GetBase()->GetApplicationOfTarget(GetGUID()) == aurApp);
+    // we've special situation here, RemoveAura called while during aura removal
+    // this kind of call is needed only when aura effect removal handler
+    // or event triggered by it expects to remove 
+    // not yet removed effects of an aura
+    if(aurApp->GetRemoveMode())
+    {
+        // remove remaining effects of an aura
+        for (uint8 itr = 0 ; itr < MAX_SPELL_EFFECTS; ++itr)
+        {
+            if (aurApp->HasEffect(itr))
+                aurApp->_HandleEffect(itr, false);
+        }
+        return;
+    }
     // no need to remove
-    if (aurApp->GetRemoveMode() || aurApp->GetBase()->IsRemoved())
+    if (aurApp->GetBase()->GetApplicationOfTarget(GetGUID()) != aurApp || aurApp->GetBase()->IsRemoved())
         return;
     uint32 spellId = aurApp->GetBase()->GetId();
     for (AuraApplicationMap::iterator iter = m_appliedAuras.lower_bound(spellId); iter != m_appliedAuras.upper_bound(spellId);)
@@ -3596,8 +3610,6 @@ void Unit::RemoveAura(Aura * aura, AuraRemoveMode mode)
         return;
     if (AuraApplication * aurApp = aura->GetApplicationOfTarget(GetGUID()))
         RemoveAura(aurApp, mode);
-    else
-        ASSERT(false);
 }
 
 void Unit::RemoveAurasDueToSpell(uint32 spellId, uint64 caster, uint8 reqEffMask, AuraRemoveMode removeMode)
@@ -11909,27 +11921,14 @@ float Unit::GetPPMProcChance(uint32 WeaponSpeed, float PPM, const SpellEntry * s
 
 void Unit::Mount(uint32 mount, uint32 VehicleId, uint32 creatureEntry)
 {
-    RemoveAurasWithInterruptFlags(AURA_INTERRUPT_FLAG_MOUNT);
-
     if (mount)
         SetUInt32Value(UNIT_FIELD_MOUNTDISPLAYID, mount);
 
     SetFlag(UNIT_FIELD_FLAGS, UNIT_FLAG_MOUNT);
 
-    // unsummon pet
     if (Player* plr = ToPlayer())
     {
-        Pet* pet = plr->GetPet();
-        if (pet)
-        {
-            Battleground *bg = ToPlayer()->GetBattleground();
-            // don't unsummon pet in arena but SetFlag UNIT_FLAG_STUNNED to disable pet's interface
-            if (bg && bg->isArena())
-                pet->SetFlag(UNIT_FIELD_FLAGS, UNIT_FLAG_STUNNED);
-            else
-                plr->UnsummonPetTemporaryIfAny();
-        }
-
+        // mount as a vehicle
         if (VehicleId)
         {
             if (CreateVehicleKit(VehicleId, creatureEntry))
@@ -11949,8 +11948,21 @@ void Unit::Mount(uint32 mount, uint32 VehicleId, uint32 creatureEntry)
                 GetVehicleKit()->InstallAllAccessories(false);
             }
         }
+
+        // unsummon pet
+        Pet* pet = plr->GetPet();
+        if (pet)
+        {
+            Battleground *bg = ToPlayer()->GetBattleground();
+            // don't unsummon pet in arena but SetFlag UNIT_FLAG_STUNNED to disable pet's interface
+            if (bg && bg->isArena())
+                pet->SetFlag(UNIT_FIELD_FLAGS, UNIT_FLAG_STUNNED);
+            else
+                plr->UnsummonPetTemporaryIfAny();
+        }
     }
 
+    RemoveAurasWithInterruptFlags(AURA_INTERRUPT_FLAG_MOUNT);
 }
 
 void Unit::Unmount()
@@ -11958,8 +11970,6 @@ void Unit::Unmount()
     if (!IsMounted())
         return;
 
-    RemoveAurasWithInterruptFlags(AURA_INTERRUPT_FLAG_NOT_MOUNTED);
-
     SetUInt32Value(UNIT_FIELD_MOUNTDISPLAYID, 0);
     RemoveFlag(UNIT_FIELD_FLAGS, UNIT_FLAG_MOUNT);
 
@@ -11967,6 +11977,20 @@ void Unit::Unmount()
     data.appendPackGUID(GetGUID());
     SendMessageToSet(&data, true);
 
+    // unmount as a vehicle
+    if (GetTypeId() == TYPEID_PLAYER && GetVehicleKit())
+    {
+        // Send other players that we are no longer a vehicle
+        WorldPacket data(SMSG_PLAYER_VEHICLE_DATA, 8+4);
+        data.appendPackGUID(GetGUID());
+        data << uint32(0);
+        this->ToPlayer()->SendMessageToSet(&data, true);
+        // Remove vehicle from player
+        RemoveVehicleKit();
+    }
+
+    RemoveAurasWithInterruptFlags(AURA_INTERRUPT_FLAG_NOT_MOUNTED);
+
     // only resummon old pet if the player is already added to a map
     // this prevents adding a pet to a not created map which would otherwise cause a crash
     // (it could probably happen when logging in after a previous crash)
@@ -11980,16 +12004,6 @@ void Unit::Unmount()
         else
             this->ToPlayer()->ResummonPetTemporaryUnSummonedIfAny();
     }
-    if (GetTypeId() == TYPEID_PLAYER && GetVehicleKit())
-    {
-        // Send other players that we are no longer a vehicle
-        WorldPacket data(SMSG_PLAYER_VEHICLE_DATA, 8+4);
-        data.appendPackGUID(GetGUID());
-        data << uint32(0);
-        this->ToPlayer()->SendMessageToSet(&data, true);
-        // Remove vehicle class from player
-        RemoveVehicleKit();
-    }
 }
 
 void Unit::SetInCombatWith(Unit* enemy)
@@ -15522,7 +15536,7 @@ void Unit::SetStunned(bool apply)
     {
         SetUInt64Value(UNIT_FIELD_TARGET, 0);
         SetFlag(UNIT_FIELD_FLAGS, UNIT_FLAG_STUNNED);
-        CastStop();
+
 //        AddUnitMovementFlag(MOVEMENTFLAG_ROOT);
 
         // Creature specific
@@ -15535,6 +15549,8 @@ void Unit::SetStunned(bool apply)
         data.append(GetPackGUID());
         data << uint32(0);
         SendMessageToSet(&data, true);
+
+        CastStop();
     }
     else
     {