Refactor event pipeline to accept typed event payloads

packages/react-native/ReactCommon/react/renderer/core/CMakeLists.txt

@@ -23,6 +23,7 @@ target_link_libraries(react_render_core
         folly_runtime
         glog
         jsi
+        logger
         react_config
         react_debug
         react_render_debug

packages/react-native/ReactCommon/react/renderer/core/EventEmitter.cpp

@@ -84,7 +84,7 @@ void EventEmitter::dispatchEvent(
   eventDispatcher->dispatchEvent(
       RawEvent(
           normalizeEventType(std::move(type)),
-          payloadFactory,
+          std::make_shared<ValueFactoryEventPayload>(payloadFactory),
           eventTarget_,
           category),
       priority);
@@ -102,7 +102,7 @@ void EventEmitter::dispatchUniqueEvent(
 
   eventDispatcher->dispatchUniqueEvent(RawEvent(
       normalizeEventType(std::move(type)),
-      payloadFactory,
+      std::make_shared<ValueFactoryEventPayload>(payloadFactory),
       eventTarget_,
       RawEvent::Category::Continuous));
 }

packages/react-native/ReactCommon/react/renderer/core/EventEmitter.h

@@ -12,9 +12,11 @@
 
 #include <folly/dynamic.h>
 #include <react/renderer/core/EventDispatcher.h>
+#include <react/renderer/core/EventPayload.h>
 #include <react/renderer/core/EventPriority.h>
 #include <react/renderer/core/EventTarget.h>
 #include <react/renderer/core/ReactPrimitives.h>
+#include <react/renderer/core/ValueFactoryEventPayload.h>
 
 namespace facebook::react {
 

packages/react-native/ReactCommon/react/renderer/core/EventPayload.h

@@ -0,0 +1,31 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#pragma once
+
+#include <jsi/jsi.h>
+
+namespace facebook::react {
+
+/**
+ * Abstract base class for all event payload types.
+ */
+struct EventPayload {
+  virtual ~EventPayload() = default;
+
+  EventPayload() = default;
+  EventPayload(const EventPayload &) = default;
+  EventPayload &operator=(const EventPayload &) = default;
+  EventPayload(EventPayload &&) = default;
+  EventPayload &operator=(EventPayload &&) = default;
+
+  virtual jsi::Value asJSIValue(jsi::Runtime &runtime) const = 0;
+};
+
+using SharedEventPayload = std::shared_ptr<const EventPayload>;
+
+} // namespace facebook::react

packages/react-native/ReactCommon/react/renderer/core/EventPipe.h

@@ -11,6 +11,7 @@
 #include <string>
 
 #include <jsi/jsi.h>
+#include <react/renderer/core/EventPayload.h>
 #include <react/renderer/core/EventTarget.h>
 #include <react/renderer/core/ReactEventPriority.h>
 #include <react/renderer/core/ValueFactory.h>
@@ -22,6 +23,6 @@ using EventPipe = std::function<void(
     const EventTarget *eventTarget,
     const std::string &type,
     ReactEventPriority priority,
-    const ValueFactory &payloadFactory)>;
+    const EventPayload &payload)>;
 
 } // namespace facebook::react

packages/react-native/ReactCommon/react/renderer/core/EventQueueProcessor.cpp

@@ -6,6 +6,7 @@
  */
 
 #include <cxxreact/JSExecutor.h>
+#include <logger/react_native_log.h>
 #include "EventEmitter.h"
 #include "EventLogger.h"
 #include "EventQueue.h"
@@ -53,12 +54,18 @@ void EventQueueProcessor::flushEvents(
       eventLogger->onEventDispatch(event.loggingTag);
     }
 
+    if (event.eventPayload == nullptr) {
+      react_native_log_error(
+          "EventQueueProcessor: Unexpected null event payload");
+      continue;
+    }
+
     eventPipe_(
         runtime,
         event.eventTarget.get(),
         event.type,
         reactPriority,
-        event.payloadFactory);
+        *event.eventPayload);
 
     if (eventLogger != nullptr) {
       eventLogger->onEventEnd(event.loggingTag);

packages/react-native/ReactCommon/react/renderer/core/RawEvent.cpp

@@ -11,11 +11,11 @@ namespace facebook::react {
 
 RawEvent::RawEvent(
     std::string type,
-    ValueFactory payloadFactory,
+    SharedEventPayload eventPayload,
     SharedEventTarget eventTarget,
     Category category)
     : type(std::move(type)),
-      payloadFactory(std::move(payloadFactory)),
+      eventPayload(std::move(eventPayload)),
       eventTarget(std::move(eventTarget)),
       category(category) {}
 

packages/react-native/ReactCommon/react/renderer/core/RawEvent.h

@@ -11,8 +11,8 @@
 #include <string>
 
 #include <react/renderer/core/EventLogger.h>
+#include <react/renderer/core/EventPayload.h>
 #include <react/renderer/core/EventTarget.h>
-#include <react/renderer/core/ValueFactory.h>
 
 namespace facebook::react {
 
@@ -60,12 +60,12 @@ struct RawEvent {
 
   RawEvent(
       std::string type,
-      ValueFactory payloadFactory,
+      SharedEventPayload eventPayload,
       SharedEventTarget eventTarget,
       Category category = Category::Unspecified);
 
   std::string type;
-  ValueFactory payloadFactory;
+  SharedEventPayload eventPayload;
   SharedEventTarget eventTarget;
   Category category;
   EventTag loggingTag{0};

packages/react-native/ReactCommon/react/renderer/core/ValueFactoryEventPayload.cpp

@@ -0,0 +1,19 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#include "ValueFactoryEventPayload.h"
+
+namespace facebook::react {
+
+ValueFactoryEventPayload::ValueFactoryEventPayload(ValueFactory factory)
+    : valueFactory_(std::move(factory)) {}
+
+jsi::Value ValueFactoryEventPayload::asJSIValue(jsi::Runtime &runtime) const {
+  return valueFactory_(runtime);
+}
+
+} // namespace facebook::react

packages/react-native/ReactCommon/react/renderer/core/ValueFactoryEventPayload.h

@@ -0,0 +1,24 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#pragma once
+
+#include <react/renderer/core/EventPayload.h>
+#include <react/renderer/core/ValueFactory.h>
+
+namespace facebook::react {
+
+class ValueFactoryEventPayload : public EventPayload {
+ public:
+  explicit ValueFactoryEventPayload(ValueFactory factory);
+  jsi::Value asJSIValue(jsi::Runtime &runtime) const override;
+
+ private:
+  ValueFactory valueFactory_;
+};
+
+} // namespace facebook::react

packages/react-native/ReactCommon/react/renderer/core/tests/EventQueueProcessorTest.cpp

@@ -11,6 +11,7 @@
 #include <react/renderer/core/EventPipe.h>
 #include <react/renderer/core/EventQueueProcessor.h>
 #include <react/renderer/core/StatePipe.h>
+#include <react/renderer/core/ValueFactoryEventPayload.h>
 
 #include <memory>
 
@@ -26,7 +27,7 @@ class EventQueueProcessorTest : public testing::Test {
                          const EventTarget * /*eventTarget*/,
                          const std::string &type,
                          ReactEventPriority priority,
-                         const ValueFactory & /*payloadFactory*/) {
+                         const EventPayload & /*payload*/) {
       eventTypes_.push_back(type);
       eventPriorities_.push_back(priority);
     };
@@ -49,7 +50,7 @@ TEST_F(EventQueueProcessorTest, singleUnspecifiedEvent) {
       *runtime_,
       {RawEvent(
           "my type",
-          dummyValueFactory_,
+          std::make_shared<ValueFactoryEventPayload>(dummyValueFactory_),
           nullptr,
           RawEvent::Category::Unspecified)});
 
@@ -63,22 +64,22 @@ TEST_F(EventQueueProcessorTest, continuousEvent) {
       *runtime_,
       {RawEvent(
            "touchStart",
-           dummyValueFactory_,
+           std::make_shared<ValueFactoryEventPayload>(dummyValueFactory_),
            nullptr,
            RawEvent::Category::ContinuousStart),
        RawEvent(
            "touchMove",
-           dummyValueFactory_,
+           std::make_shared<ValueFactoryEventPayload>(dummyValueFactory_),
            nullptr,
            RawEvent::Category::Unspecified),
        RawEvent(
            "touchEnd",
-           dummyValueFactory_,
+           std::make_shared<ValueFactoryEventPayload>(dummyValueFactory_),
            nullptr,
            RawEvent::Category::ContinuousEnd),
        RawEvent(
            "custom event",
-           dummyValueFactory_,
+           std::make_shared<ValueFactoryEventPayload>(dummyValueFactory_),
            nullptr,
            RawEvent::Category::Unspecified)});
 
@@ -103,7 +104,7 @@ TEST_F(EventQueueProcessorTest, alwaysContinuousEvent) {
       {
           RawEvent(
               "onScroll",
-              dummyValueFactory_,
+              std::make_shared<ValueFactoryEventPayload>(dummyValueFactory_),
               nullptr,
               RawEvent::Category::Continuous),
       });
@@ -120,7 +121,7 @@ TEST_F(EventQueueProcessorTest, alwaysDiscreteEvent) {
       {
           RawEvent(
               "onChange",
-              dummyValueFactory_,
+              std::make_shared<ValueFactoryEventPayload>(dummyValueFactory_),
               nullptr,
               RawEvent::Category::Discrete),
       });

packages/react-native/ReactCommon/react/renderer/scheduler/Scheduler.cpp

@@ -60,11 +60,11 @@ Scheduler::Scheduler(
                        const EventTarget *eventTarget,
                        const std::string &type,
                        ReactEventPriority priority,
-                       const ValueFactory &payloadFactory) {
+                       const EventPayload &payload) {
     uiManager->visitBinding(
         [&](UIManagerBinding const &uiManagerBinding) {
           uiManagerBinding.dispatchEvent(
-              runtime, eventTarget, type, priority, payloadFactory);
+              runtime, eventTarget, type, priority, payload);
         },
         runtime);
     if (runtimeScheduler != nullptr) {

packages/react-native/ReactCommon/react/renderer/uimanager/UIManagerBinding.cpp

@@ -93,10 +93,10 @@ void UIManagerBinding::dispatchEvent(
     EventTarget const *eventTarget,
     std::string const &type,
     ReactEventPriority priority,
-    ValueFactory const &payloadFactory) const {
+    const EventPayload &eventPayload) const {
   SystraceSection s("UIManagerBinding::dispatchEvent", "type", type);
 
-  auto payload = payloadFactory(runtime);
+  auto payload = eventPayload.asJSIValue(runtime);
 
   // If a payload is null, the factory has decided to cancel the event
   if (payload.isNull()) {

packages/react-native/ReactCommon/react/renderer/uimanager/UIManagerBinding.h

@@ -52,7 +52,7 @@ class UIManagerBinding : public jsi::HostObject {
       EventTarget const *eventTarget,
       std::string const &type,
       ReactEventPriority priority,
-      ValueFactory const &payloadFactory) const;
+      const EventPayload &payload) const;
 
   /*
    * Invalidates the binding and underlying UIManager.