Core/Spells: Implement SPELL_ATTR4_DAMAGE_DOESNT_BREAK_AURAS. Damage from spells with this attribute flag shouldn't break breakable by damage auras

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

@@ -591,7 +591,13 @@ uint32 Unit::DealDamage(Unit *pVictim, uint32 damage, CleanDamage const* cleanDa
     if (damagetype != NODAMAGE)
     {
         // interrupting auras with AURA_INTERRUPT_FLAG_DAMAGE before checking !damage (absorbed damage breaks that type of auras)
-        pVictim->RemoveAurasWithInterruptFlags(AURA_INTERRUPT_FLAG_TAKE_DAMAGE, spellProto ? spellProto->Id : 0);
+        if (spellProto)
+        {
+            if (!(spellProto->AttributesEx4 & SPELL_ATTR4_DAMAGE_DOESNT_BREAK_AURAS))
+                pVictim->RemoveAurasWithInterruptFlags(AURA_INTERRUPT_FLAG_TAKE_DAMAGE, spellProto->Id);
+        }
+        else
+            pVictim->RemoveAurasWithInterruptFlags(AURA_INTERRUPT_FLAG_TAKE_DAMAGE, 0);
 
         // We're going to call functions which can modify content of the list during iteration over it's elements
         // Let's copy the list so we can prevent iterator invalidation

src/server/game/Miscellaneous/SharedDefines.h

@@ -421,7 +421,7 @@ enum SpellAttr4
     SPELL_ATTR4_UNK11                            = 0x00000800, // 11
     SPELL_ATTR4_UNK12                            = 0x00001000, // 12
     SPELL_ATTR4_UNK13                            = 0x00002000, // 13
-    SPELL_ATTR4_UNK14                            = 0x00004000, // 14
+    SPELL_ATTR4_DAMAGE_DOESNT_BREAK_AURAS        = 0x00004000, // 14 doesn't break auras by damage from these spells
     SPELL_ATTR4_UNK15                            = 0x00008000, // 15
     SPELL_ATTR4_NOT_USABLE_IN_ARENA              = 0x00010000, // 16 not usable in arena
     SPELL_ATTR4_USABLE_IN_ARENA                  = 0x00020000, // 17 usable in arena