Add Suspensey Images behind a Flag

fixtures/view-transition/src/components/Page.js

@@ -41,6 +41,12 @@ function Component() {
         transitions['enter-slide-right'] + ' ' + transitions['exit-slide-left']
       }>
       <p className="roboto-font">Slide In from Left, Slide Out to Right</p>
+      <p>
+        <img
+          src="https://react.dev/_next/image?url=%2Fimages%2Fteam%2Fsebmarkbage.jpg&w=3840&q=75"
+          width="300"
+        />
+      </p>
     </ViewTransition>
   );
 }

packages/react-art/src/ReactFiberConfigART.js

@@ -596,14 +596,22 @@ export function maySuspendCommit(type, props) {
   return false;
 }
 
+export function maySuspendCommitOnUpdate(type, oldProps, newProps) {
+  return false;
+}
+
+export function maySuspendCommitInSyncRender(type, props) {
+  return false;
+}
+
 export function preloadInstance(type, props) {
   // Return true to indicate it's already loaded
   return true;
 }
 
 export function startSuspendingCommit() {}
 
-export function suspendInstance(type, props) {}
+export function suspendInstance(instance, type, props) {}
 
 export function suspendOnActiveViewTransition(container) {}
 

packages/react-dom-bindings/src/client/ReactFiberConfigDOM.js

@@ -103,6 +103,7 @@ import {
   disableLegacyMode,
   enableMoveBefore,
   disableCommentsAsDOMContainers,
+  enableSuspenseyImages,
 } from 'shared/ReactFeatureFlags';
 import {
   HostComponent,
@@ -145,6 +146,10 @@ export type Props = {
   is?: string,
   size?: number,
   multiple?: boolean,
+  src?: string,
+  srcSet?: string,
+  loading?: 'eager' | 'lazy',
+  onLoad?: (event: any) => void,
   ...
 };
 type RawProps = {
@@ -769,9 +774,9 @@ export function commitMount(
       // only need to assign one. And Safari just never triggers a new load event which means this technique
       // is already a noop regardless of which properties are assigned. We should revisit if browsers update
       // this heuristic in the future.
-      if ((newProps: any).src) {
+      if (newProps.src) {
         ((domElement: any): HTMLImageElement).src = (newProps: any).src;
-      } else if ((newProps: any).srcSet) {
+      } else if (newProps.srcSet) {
         ((domElement: any): HTMLImageElement).srcset = (newProps: any).srcSet;
       }
       return;
@@ -4974,6 +4979,36 @@ export function isHostHoistableType(
 }
 
 export function maySuspendCommit(type: Type, props: Props): boolean {
+  if (!enableSuspenseyImages) {
+    return false;
+  }
+  // Suspensey images are the default, unless you opt-out of with either
+  // loading="lazy" or onLoad={...} which implies you're ok waiting.
+  return (
+    type === 'img' &&
+    props.src != null &&
+    props.src !== '' &&
+    props.onLoad == null &&
+    props.loading !== 'lazy'
+  );
+}
+
+export function maySuspendCommitOnUpdate(
+  type: Type,
+  oldProps: Props,
+  newProps: Props,
+): boolean {
+  return (
+    maySuspendCommit(type, newProps) &&
+    (newProps.src !== oldProps.src || newProps.srcSet !== oldProps.srcSet)
+  );
+}
+
+export function maySuspendCommitInSyncRender(
+  type: Type,
+  props: Props,
+): boolean {
+  // TODO: Allow sync lanes to suspend too with an opt-in.
   return false;
 }
 
@@ -4985,7 +5020,13 @@ export function mayResourceSuspendCommit(resource: Resource): boolean {
 }
 
 export function preloadInstance(type: Type, props: Props): boolean {
-  return true;
+  // We don't need to preload Suspensey images because the browser will
+  // load them early once we set the src.
+  // We indicate that all images are not yet loaded and if they're able
+  // to hit cache we let the decode() do that. Even if we did maintain
+  // our own cache to know this, it's not a guarantee that the browser
+  // keeps it in decoded memory.
+  return false;
 }
 
 export function preloadResource(resource: Resource): boolean {
@@ -5022,8 +5063,38 @@ export function startSuspendingCommit(): void {
   };
 }
 
-export function suspendInstance(type: Type, props: Props): void {
-  return;
+const SUSPENSEY_IMAGE_TIMEOUT = 500;
+
+export function suspendInstance(
+  instance: Instance,
+  type: Type,
+  props: Props,
+): void {
+  if (!enableSuspenseyImages) {
+    return;
+  }
+  if (suspendedState === null) {
+    throw new Error(
+      'Internal React Error: suspendedState null when it was expected to exists. Please report this as a React bug.',
+    );
+  }
+  const state = suspendedState;
+  if (
+    // $FlowFixMe[prop-missing]
+    typeof instance.decode === 'function' &&
+    typeof setTimeout === 'function'
+  ) {
+    // If this browser supports decode() API, we use it to suspend waiting on the image.
+    // The loading should have already started at this point, so it should be enough to
+    // just call decode() which should also wait for the data to finish loading.
+    state.count++;
+    const ping = onUnsuspend.bind(state);
+    Promise.race([
+      // $FlowFixMe[prop-missing]
+      instance.decode(),
+      new Promise(resolve => setTimeout(resolve, SUSPENSEY_IMAGE_TIMEOUT)),
+    ]).then(ping, ping);
+  }
 }
 
 export function suspendResource(

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

@@ -577,13 +577,32 @@ export function maySuspendCommit(type: Type, props: Props): boolean {
   return false;
 }
 
+export function maySuspendCommitOnUpdate(
+  type: Type,
+  oldProps: Props,
+  newProps: Props,
+): boolean {
+  return false;
+}
+
+export function maySuspendCommitInSyncRender(
+  type: Type,
+  props: Props,
+): boolean {
+  return false;
+}
+
 export function preloadInstance(type: Type, props: Props): boolean {
   return true;
 }
 
 export function startSuspendingCommit(): void {}
 
-export function suspendInstance(type: Type, props: Props): void {}
+export function suspendInstance(
+  instance: Instance,
+  type: Type,
+  props: Props,
+): void {}
 
 export function suspendOnActiveViewTransition(container: Container): void {}
 

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

@@ -735,14 +735,33 @@ export function maySuspendCommit(type: Type, props: Props): boolean {
   return false;
 }
 
+export function maySuspendCommitOnUpdate(
+  type: Type,
+  oldProps: Props,
+  newProps: Props,
+): boolean {
+  return false;
+}
+
+export function maySuspendCommitInSyncRender(
+  type: Type,
+  props: Props,
+): boolean {
+  return false;
+}
+
 export function preloadInstance(type: Type, props: Props): boolean {
   // Return false to indicate it's already loaded
   return true;
 }
 
 export function startSuspendingCommit(): void {}
 
-export function suspendInstance(type: Type, props: Props): void {}
+export function suspendInstance(
+  instance: Instance,
+  type: Type,
+  props: Props,
+): void {}
 
 export function suspendOnActiveViewTransition(container: Container): void {}
 

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

@@ -320,7 +320,11 @@ function createReactNoop(reconciler: Function, useMutation: boolean) {
     suspenseyCommitSubscription = null;
   }
 
-  function suspendInstance(type: string, props: Props): void {
+  function suspendInstance(
+    instance: Instance,
+    type: string,
+    props: Props,
+  ): void {
     const src = props.src;
     if (type === 'suspensey-thing' && typeof src === 'string') {
       // Attach a listener to the suspensey thing and create a subscription
@@ -624,6 +628,26 @@ function createReactNoop(reconciler: Function, useMutation: boolean) {
       return type === 'suspensey-thing' && typeof props.src === 'string';
     },
 
+    maySuspendCommitOnUpdate(
+      type: string,
+      oldProps: Props,
+      newProps: Props,
+    ): boolean {
+      // Asks whether it's possible for this combination of type and props
+      // to ever need to suspend. This is different from asking whether it's
+      // currently ready because even if it's ready now, it might get purged
+      // from the cache later.
+      return (
+        type === 'suspensey-thing' &&
+        typeof newProps.src === 'string' &&
+        newProps.src !== oldProps.src
+      );
+    },
+
+    maySuspendCommitInSyncRender(type: string, props: Props): boolean {
+      return true;
+    },
+
     mayResourceSuspendCommit(resource: mixed): boolean {
       throw new Error(
         'Resources are not implemented for React Noop yet. This method should not be called',