Core/Spells: Replaced assert with startup error log

(cherry picked from commit 8043b71708e2efd380c7a1f6a738a1e9e497706d)

2 files changed, 32 insertions, 1 deletions

diff --git a/src/server/game/Spells/Auras/SpellAuraEffects.cpp b/src/server/game/Spells/Auras/SpellAuraEffects.cpp
index 4890f570df6..70dd3371866 100644
--- a/src/server/game/Spells/Auras/SpellAuraEffects.cpp
+++ b/src/server/game/Spells/Auras/SpellAuraEffects.cpp
@@ -42,6 +42,7 @@
 #include "Spell.h"
 #include "SpellHistory.h"
 #include "SpellMgr.h"
+#include "SpellScript.h"
 #include "ThreatManager.h"
 #include "Unit.h"
 #include "Util.h"
@@ -1015,6 +1016,32 @@ void AuraEffect::CalculateSpellMod()
             break;
     }
     GetBase()->CallScriptEffectCalcSpellModHandlers(this, m_spellmod);
+
+    // validate modifier
+    if (m_spellmod)
+    {
+        bool isValid = true;
+        auto logErrors = [&] { return std::ranges::any_of(GetBase()->m_loadedScripts, [](AuraScript const* script) { return script->DoEffectCalcSpellMod.size() > 0; }); };
+        if (AsUnderlyingType(m_spellmod->op) >= MAX_SPELLMOD)
+        {
+            isValid = false;
+            if (logErrors())
+                TC_LOG_ERROR("spells.aura.effect", "Aura script for spell id {} created invalid spell modifier op {}", GetId(), AsUnderlyingType(m_spellmod->op));
+        }
+
+        if (m_spellmod->type >= SPELLMOD_END)
+        {
+            isValid = false;
+            if (logErrors())
+                TC_LOG_ERROR("spells.aura.effect", "Aura script for spell id {} created invalid spell modifier type {}", GetId(), AsUnderlyingType(m_spellmod->type));
+        }
+
+        if (!isValid)
+        {
+            delete m_spellmod;
+            m_spellmod = nullptr;
+        }
+    }
 }
 
 void AuraEffect::ChangeAmount(int32 newAmount, bool mark, bool onStackOrReapply, AuraEffect const* triggeredBy /* = nullptr */)
diff --git a/src/server/game/Spells/SpellMgr.cpp b/src/server/game/Spells/SpellMgr.cpp
index ac2568f00f3..d79ae4627df 100644
--- a/src/server/game/Spells/SpellMgr.cpp
+++ b/src/server/game/Spells/SpellMgr.cpp
@@ -2523,7 +2523,11 @@ void SpellMgr::LoadSpellInfoStore()
             case SPELL_AURA_ADD_PCT_MODIFIER:
             case SPELL_AURA_ADD_PCT_MODIFIER_BY_SPELL_LABEL:
             case SPELL_AURA_ADD_FLAT_MODIFIER_BY_SPELL_LABEL:
-                ASSERT(effect->EffectMiscValue[0] < MAX_SPELLMOD, "MAX_SPELLMOD must be at least %d", effect->EffectMiscValue[0] + 1);
+                if (effect->EffectMiscValue[0] >= MAX_SPELLMOD)
+                {
+                    TC_LOG_ERROR("server.loading", "Invalid spell modifier type {} found on spell {} effect index {}, consider increasing MAX_SPELLMOD",
+                        effect->EffectMiscValue[0], effect->SpellID, effect->EffectIndex);
+                }
                 break;
             default:
                 break;