From 539c2df378040513f31a0dbce6e5d4755ec204fb Mon Sep 17 00:00:00 2001
From: smallmodel <15067410+smallmodel@users.noreply.github.com>
Date: Thu, 16 Jan 2025 23:25:26 +0100
Subject: [PATCH] Check for valid event on listener and print an error if the
 command cannot be executed

---
 code/script/scriptvm.cpp | 17 +++++++++++++++++
 code/script/scriptvm.h   |  1 +
 2 files changed, 18 insertions(+)

diff --git a/code/script/scriptvm.cpp b/code/script/scriptvm.cpp
index 3e70d985..cc48908f 100644
--- a/code/script/scriptvm.cpp
+++ b/code/script/scriptvm.cpp
@@ -541,6 +541,8 @@ void ScriptVM::executeCommandInternal<false>(
 )
 {
     transferVarsToEvent(ev, fromVar, iParamCount);
+    checkValidEvent(ev, listener);
+
     listener->ProcessScriptEvent(ev);
 }
 
@@ -550,6 +552,7 @@ void ScriptVM::executeCommandInternal<true>(
 )
 {
     transferVarsToEvent(ev, fromVar, iParamCount);
+    checkValidEvent(ev, listener);
 
     try {
         listener->ProcessScriptEvent(ev);
@@ -595,6 +598,20 @@ void ScriptVM::transferVarsToEvent(Event& ev, ScriptVariable *fromVar, op_parmNu
     ev.CopyValues(fromVar, count);
 }
 
+void ScriptVM::checkValidEvent(Event& ev, Listener* listener) {
+    ClassDef *c = listener->classinfo();
+
+    if (!c->GetDef(&ev)) {
+        if (listener == m_Thread) {
+            ScriptError("Failed execution of command '%s'", ev.getName());
+        } else if (listener->isSubclassOf(SimpleEntity)) {
+            ScriptError("Failed execution of command '%s' for class '%s' Targetname '%s'", ev.getName(), c->classname, static_cast<SimpleEntity*>(listener)->targetname.c_str());
+        } else {
+            ScriptError("Failed execution of command '%s' for class '%s'", ev.getName(), c->classname);
+        }
+    }
+}
+
 bool ScriptVM::executeGetter(Listener *listener, op_evName_t eventName)
 {
     int eventNum = Event::FindGetterEventNum(eventName);
diff --git a/code/script/scriptvm.h b/code/script/scriptvm.h
index 7f4b0e6c..ece0af2f 100644
--- a/code/script/scriptvm.h
+++ b/code/script/scriptvm.h
@@ -177,6 +177,7 @@ private:
     bool executeGetter(Listener *listener, op_evName_t eventName);
     bool executeSetter(Listener *listener, op_evName_t eventName);
     void transferVarsToEvent(Event& ev, ScriptVariable *fromVar, op_parmNum_t count);
+    void checkValidEvent(Event& ev, Listener *listener);
 
     void            loadTopInternal(Listener *listener);
     ScriptVariable *storeTopInternal(Listener *listener);