Emit errors

2 files changed, 37 insertions, 2 deletions

diff --git a/src/bun.js/bindings/webcore/EventEmitter.cpp b/src/bun.js/bindings/webcore/EventEmitter.cpp
index 2c80e9cc2..8d34ab7a2 100644
--- a/src/bun.js/bindings/webcore/EventEmitter.cpp
+++ b/src/bun.js/bindings/webcore/EventEmitter.cpp
@@ -37,7 +37,6 @@ bool EventEmitter::addListener(const Identifier& eventType, Ref<EventListener>&&
             return false;
     }
 
-
     eventListenersDidChange();
     return true;
 }
@@ -205,7 +204,27 @@ void EventEmitter::innerInvokeEventListeners(const Identifier& eventType, Simple
         if (JSC::JSObject* jsFunction = registeredListener->callback().jsFunction()) {
             JSC::JSGlobalObject* lexicalGlobalObject = jsFunction->globalObject();
             auto callData = JSC::getCallData(jsFunction);
-            JSC::call(jsFunction->globalObject(), jsFunction, callData, JSC::jsUndefined(), arguments);
+            if (callData.type == JSC::CallData::Type::None)
+                continue;
+
+            WTF::NakedPtr<JSC::Exception> exceptionPtr;
+            JSC::call(jsFunction->globalObject(), jsFunction, callData, JSC::jsUndefined(), arguments, exceptionPtr);
+            if (auto* exception = exceptionPtr.get()) {
+                auto errorIdentifier = JSC::Identifier::fromString(vm, eventNames().errorEvent);
+                auto hasErrorListener = this->hasActiveEventListeners(errorIdentifier);
+                if (!hasErrorListener || eventType == errorIdentifier) {
+                    // If the event type is error, report the exception to the console.
+                    Bun__reportError(lexicalGlobalObject, JSValue::encode(JSValue(exception)));
+                } else if (hasErrorListener) {
+                    MarkedArgumentBuffer expcep;
+                    JSValue errorValue = exception->value();
+                    if (!errorValue) {
+                        errorValue = JSC::jsUndefined();
+                    }
+                    expcep.append(errorValue);
+                    fireEventListeners(errorIdentifier, WTFMove(expcep));
+                }
+            }
         }
     }
 }
diff --git a/src/bun.js/bindings/webcore/EventEmitter.h b/src/bun.js/bindings/webcore/EventEmitter.h
index eb6fa2e77..4aa143604 100644
--- a/src/bun.js/bindings/webcore/EventEmitter.h
+++ b/src/bun.js/bindings/webcore/EventEmitter.h
@@ -65,6 +65,11 @@ public:
     bool hasEventListeners() const;
     bool hasEventListeners(const Identifier& eventType) const;
     bool hasActiveEventListeners(const Identifier& eventType) const;
+    bool hasEventListeners(JSC::VM& vm, ASCIILiteral eventType) const;
+
+    unsigned getMaxListeners() const { return m_maxListeners; };
+
+    void setMaxListeners(unsigned count);
 
     Vector<Identifier> eventTypes();
     const SimpleEventListenerVector& eventListeners(const Identifier& eventType);
@@ -93,6 +98,7 @@ private:
     void invalidateEventListenerRegions();
 
     EventEmitterData m_eventTargetData;
+    unsigned m_maxListeners { 10 };
 };
 
 inline const EventEmitterData* EventEmitter::eventTargetData() const
@@ -118,4 +124,14 @@ inline bool EventEmitter::hasEventListeners(const Identifier& eventType) const
     return data && data->eventListenerMap.contains(eventType);
 }
 
+inline bool EventEmitter::hasEventListeners(JSC::VM& vm, ASCIILiteral eventType) const
+{
+    return this->hasEventListeners(Identifier::fromString(vm, eventType));
+}
+
+inline void EventEmitter::setMaxListeners(unsigned count)
+{
+    this->m_maxListeners = count;
+}
+
 } // namespace WebCore