Experimental event API: Support EventComponent onUnmount responder callback (#15335)

Author: trueadm

packages/react-art/src/ReactARTHostConfig.js

@@ -442,6 +442,13 @@ export function unhideTextInstance(textInstance, text): void {
 export function handleEventComponent(
   eventResponder: ReactEventResponder,
   rootContainerInstance: Container,
+) {
+  throw new Error('Not yet implemented.');
+}
+
+export function unmountEventComponent(
+  eventResponder: ReactEventResponder,
+  rootContainerInstance: Container,
   internalInstanceHandle: Object,
 ): void {
   throw new Error('Not yet implemented.');

packages/react-dom/src/client/ReactDOMHostConfig.js

@@ -45,6 +45,7 @@ import dangerousStyleValue from '../shared/dangerousStyleValue';
 
 import type {DOMContainer} from './ReactDOM';
 import type {ReactEventResponder} from 'shared/ReactTypes';
+import {unmountEventResponder} from '../events/DOMEventResponderSystem';
 import {REACT_EVENT_TARGET_TOUCH_HIT} from 'shared/ReactSymbols';
 import {canUseDOM} from 'shared/ExecutionEnvironment';
 
@@ -890,7 +891,6 @@ export function didNotFindHydratableSuspenseInstance(
 export function handleEventComponent(
   eventResponder: ReactEventResponder,
   rootContainerInstance: Container,
-  internalInstanceHandle: Object,
 ): void {
   if (enableEventAPI) {
     const rootElement = rootContainerInstance.ownerDocument;
@@ -901,6 +901,17 @@ export function handleEventComponent(
   }
 }
 
+export function unmountEventComponent(
+  eventResponder: ReactEventResponder,
+  rootContainerInstance: Container,
+  internalInstanceHandle: Object,
+): void {
+  if (enableEventAPI) {
+    // TODO stop listening to targetEventTypes
+    unmountEventResponder(eventResponder, internalInstanceHandle);
+  }
+}
+
 export function getEventTargetChildElement(
   type: Symbol | number,
   props: Props,

packages/react-dom/src/events/DOMEventResponderSystem.js

@@ -364,10 +364,17 @@ function handleTopLevelType(
   if (state === null && responder.createInitialState !== undefined) {
     state = fiber.stateNode.state = responder.createInitialState(props);
   }
+  const previousFiber = currentFiber;
+  const previousResponder = currentResponder;
   currentFiber = fiber;
   currentResponder = responder;
 
-  responder.onEvent(responderEvent, eventResponderContext, props, state);
+  try {
+    responder.onEvent(responderEvent, eventResponderContext, props, state);
+  } finally {
+    currentFiber = previousFiber;
+    currentResponder = previousResponder;
+  }
 }
 
 export function runResponderEventsInBatch(
@@ -413,3 +420,30 @@ export function runResponderEventsInBatch(
     processEventQueue();
   }
 }
+
+export function unmountEventResponder(
+  responder: ReactEventResponder,
+  fiber: Fiber,
+): void {
+  const onUnmount = responder.onUnmount;
+  if (onUnmount !== undefined) {
+    let {props, state} = fiber.stateNode;
+    const previousEventQueue = currentEventQueue;
+    const previousFiber = currentFiber;
+    const previousResponder = currentResponder;
+    currentEventQueue = createEventQueue();
+    currentFiber = fiber;
+    currentResponder = responder;
+    try {
+      onUnmount(eventResponderContext, props, state);
+    } finally {
+      currentEventQueue = previousEventQueue;
+      currentFiber = previousFiber;
+      currentResponder = previousResponder;
+    }
+  }
+  if (currentOwner === fiber) {
+    // TODO fire owner changed callback
+    currentOwner = null;
+  }
+}

packages/react-dom/src/events/__tests__/DOMEventResponderSystem-test.internal.js

@@ -13,10 +13,11 @@ let React;
 let ReactFeatureFlags;
 let ReactDOM;
 
-function createReactEventComponent(targetEventTypes, onEvent) {
+function createReactEventComponent(targetEventTypes, onEvent, onUnmount) {
   const testEventResponder = {
     targetEventTypes,
     onEvent,
+    onUnmount,
   };
 
   return {
@@ -316,4 +317,26 @@ describe('DOMEventResponderSystem', () => {
 
     expect(eventLog).toEqual(['press', 'longpress', 'longpresschange']);
   });
+
+  it('the event responder onUnmount() function should fire', () => {
+    let onUnmountFired = 0;
+
+    const EventComponent = createReactEventComponent(
+      [],
+      (event, context, props) => {},
+      () => {
+        onUnmountFired++;
+      },
+    );
+
+    const Test = () => (
+      <EventComponent>
+        <button />
+      </EventComponent>
+    );
+
+    ReactDOM.render(<Test />, container);
+    ReactDOM.render(null, container);
+    expect(onUnmountFired).toEqual(1);
+  });
 });

packages/react-events/src/Press.js

@@ -209,6 +209,7 @@ function unmountResponder(
 ): void {
   if (state.isPressed) {
     state.isPressed = false;
+    context.removeRootEventTypes(rootEventTypes);
     dispatchPressEndEvents(context, props, state);
     if (state.longPressTimeout !== null) {
       clearTimeout(state.longPressTimeout);
@@ -429,7 +430,6 @@ const PressResponder = {
       }
     }
   },
-  // TODO This method doesn't work as of yet
   onUnmount(context: ResponderContext, props: PressProps, state: PressState) {
     unmountResponder(context, props, state);
   },

packages/react-native-renderer/src/ReactFabricHostConfig.js

@@ -437,6 +437,13 @@ export function replaceContainerChildren(
 export function handleEventComponent(
   eventResponder: ReactEventResponder,
   rootContainerInstance: Container,
+) {
+  throw new Error('Not yet implemented.');
+}
+
+export function unmountEventComponent(
+  eventResponder: ReactEventResponder,
+  rootContainerInstance: Container,
   internalInstanceHandle: Object,
 ): void {
   throw new Error('Not yet implemented.');

packages/react-native-renderer/src/ReactNativeHostConfig.js

@@ -496,11 +496,18 @@ export function unhideTextInstance(
 export function handleEventComponent(
   eventResponder: ReactEventResponder,
   rootContainerInstance: Container,
-  internalInstanceHandle: Object,
 ) {
   throw new Error('Not yet implemented.');
 }
 
+export function unmountEventComponent(
+  eventResponder: ReactEventResponder,
+  rootContainerInstance: Container,
+  internalInstanceHandle: Object,
+): void {
+  throw new Error('Not yet implemented.');
+}
+
 export function getEventTargetChildElement(
   type: Symbol | number,
   props: Props,

packages/react-noop-renderer/src/createReactNoop.js

@@ -431,7 +431,11 @@ function createReactNoop(reconciler: Function, useMutation: boolean) {
     isPrimaryRenderer: true,
     supportsHydration: false,
 
-    handleEventComponent() {
+    handleEventComponent(): void {
+      // NO-OP
+    },
+
+    unmountEventComponent(): void {
       // NO-OP
     },
 

packages/react-reconciler/src/ReactFiber.js

@@ -626,6 +626,7 @@ export function createFiberFromEventComponent(
   fiber.stateNode = {
     context: null,
     props: pendingProps,
+    rootInstance: null,
     state: null,
   };
   fiber.expirationTime = expirationTime;

packages/react-reconciler/src/ReactFiberCommitWork.js

@@ -44,6 +44,7 @@ import {
   IncompleteClassComponent,
   MemoComponent,
   SimpleMemoComponent,
+  EventComponent,
   EventTarget,
 } from 'shared/ReactWorkTags';
 import {
@@ -92,6 +93,7 @@ import {
   hideTextInstance,
   unhideInstance,
   unhideTextInstance,
+  unmountEventComponent,
   commitEventTarget,
 } from './ReactFiberHostConfig';
 import {
@@ -745,6 +747,14 @@ function commitUnmount(current: Fiber): void {
       }
       return;
     }
+    case EventComponent: {
+      if (enableEventAPI) {
+        const rootContainerInstance = current.stateNode.rootInstance;
+        const responder = current.type.responder;
+        unmountEventComponent(responder, rootContainerInstance, current);
+        current.stateNode = null;
+      }
+    }
   }
 }