Cleanup enableServerComponentKeys flag (#28743)

Cleanup enableServerComponentKeys flag

Flag is `true` everywhere but RN where it doesn't apply.

packages/react-client/src/__tests__/ReactFlight-test.js

@@ -1694,7 +1694,6 @@ describe('ReactFlight', () => {
     expect(errors).toEqual([]);
   });
 
-  // @gate enableServerComponentKeys
   it('preserves state when keying a server component', async () => {
     function StatefulClient({name}) {
       const [state] = React.useState(name.toLowerCase());
@@ -1751,7 +1750,6 @@ describe('ReactFlight', () => {
     );
   });
 
-  // @gate enableServerComponentKeys
   it('does not inherit keys of children inside a server component', async () => {
     function StatefulClient({name, initial}) {
       const [state] = React.useState(initial);
@@ -1824,7 +1822,6 @@ describe('ReactFlight', () => {
     );
   });
 
-  // @gate enableServerComponentKeys
   it('shares state between single return and array return in a parent', async () => {
     function StatefulClient({name, initial}) {
       const [state] = React.useState(initial);
@@ -2065,7 +2062,6 @@ describe('ReactFlight', () => {
     );
   });
 
-  // @gate enableServerComponentKeys
   it('preserves state with keys split across async work', async () => {
     let resolve;
     const promise = new Promise(r => (resolve = r));

packages/react-server/src/ReactFlightServer.js

@@ -15,7 +15,6 @@ import {
   enableBinaryFlight,
   enablePostpone,
   enableTaint,
-  enableServerComponentKeys,
   enableRefAsProp,
   enableServerComponentLogs,
 } from 'shared/ReactFeatureFlags';
@@ -993,7 +992,7 @@ function renderFragment(
   task: Task,
   children: $ReadOnlyArray<ReactClientValue>,
 ): ReactJSONValue {
-  if (enableServerComponentKeys && task.keyPath !== null) {
+  if (task.keyPath !== null) {
     // We have a Server Component that specifies a key but we're now splitting
     // the tree using a fragment.
     const fragment = [
@@ -1052,7 +1051,7 @@ function renderAsyncFragment(
   children: $AsyncIterable<ReactClientValue, ReactClientValue, void>,
   getAsyncIterator: () => $AsyncIterator<any, any, any>,
 ): ReactJSONValue {
-  if (enableServerComponentKeys && task.keyPath !== null) {
+  if (task.keyPath !== null) {
     // We have a Server Component that specifies a key but we're now splitting
     // the tree using a fragment.
     const fragment = [
@@ -1095,11 +1094,6 @@ function renderClientElement(
   props: any,
   owner: null | ReactComponentInfo, // DEV-only
 ): ReactJSONValue {
-  if (!enableServerComponentKeys) {
-    return __DEV__
-      ? [REACT_ELEMENT_TYPE, type, key, props, owner]
-      : [REACT_ELEMENT_TYPE, type, key, props];
-  }
   // We prepend the terminal client element that actually gets serialized with
   // the keys of any Server Components which are not serialized.
   const keyPath = task.keyPath;
@@ -1266,7 +1260,7 @@ function createTask(
   if (typeof model === 'object' && model !== null) {
     // If we're about to write this into a new task we can assign it an ID early so that
     // any other references can refer to the value we're about to write.
-    if (enableServerComponentKeys && (keyPath !== null || implicitSlot)) {
+    if (keyPath !== null || implicitSlot) {
       // If we're in some kind of context we can't necessarily reuse this object depending
       // what parent components are used.
     } else {
@@ -1756,10 +1750,7 @@ function renderModelDestructive(
         const writtenObjects = request.writtenObjects;
         const existingId = writtenObjects.get(value);
         if (existingId !== undefined) {
-          if (
-            enableServerComponentKeys &&
-            (task.keyPath !== null || task.implicitSlot)
-          ) {
+          if (task.keyPath !== null || task.implicitSlot) {
             // If we're in some kind of context we can't reuse the result of this render or
             // previous renders of this element. We only reuse elements if they're not wrapped
             // by another Server Component.
@@ -1889,10 +1880,7 @@ function renderModelDestructive(
     // $FlowFixMe[method-unbinding]
     if (typeof value.then === 'function') {
       if (existingId !== undefined) {
-        if (
-          enableServerComponentKeys &&
-          (task.keyPath !== null || task.implicitSlot)
-        ) {
+        if (task.keyPath !== null || task.implicitSlot) {
           // If we're in some kind of context we can't reuse the result of this render or
           // previous renders of this element. We only reuse Promises if they're not wrapped
           // by another Server Component.

packages/shared/ReactFeatureFlags.js

@@ -169,9 +169,6 @@ export const enableFilterEmptyStringAttributesDOM = true;
 // Disabled caching behavior of `react/cache` in client runtimes.
 export const disableClientCache = true;
 
-// Changes Server Components Reconciliation when they have keys
-export const enableServerComponentKeys = true;
-
 /**
  * Enables a new error detection for infinite render loops from updates caused
  * by setState or similar outside of the component owning the state.

packages/shared/forks/ReactFeatureFlags.native-fb.js

@@ -94,7 +94,6 @@ export const enableFizzExternalRuntime = true;
 export const enableUseDeferredValueInitialArg = true;
 export const disableClientCache = true;
 
-export const enableServerComponentKeys = true;
 export const enableServerComponentLogs = true;
 
 export const enableReactTestRendererWarning = false;

packages/shared/forks/ReactFeatureFlags.native-oss.js

@@ -54,7 +54,6 @@ export const enableUnifiedSyncLane = __NEXT_RN_MAJOR__;
 export const enableFizzExternalRuntime = __NEXT_RN_MAJOR__; // DOM-only
 export const enableBinaryFlight = __NEXT_RN_MAJOR__; // DOM-only
 export const enableFlightReadableStream = __NEXT_RN_MAJOR__; // DOM-only
-export const enableServerComponentKeys = __NEXT_RN_MAJOR__;
 export const enableServerComponentLogs = __NEXT_RN_MAJOR__;
 
 // DEV-only but enabled in the next RN Major.

packages/shared/forks/ReactFeatureFlags.test-renderer.js

@@ -74,7 +74,6 @@ export const passChildrenWhenCloningPersistedNodes = false;
 export const enableUseDeferredValueInitialArg = __EXPERIMENTAL__;
 export const disableClientCache = true;
 
-export const enableServerComponentKeys = true;
 export const enableServerComponentLogs = true;
 export const enableInfiniteRenderLoopDetection = false;
 export const enableEarlyReturnForPropDiffing = false;

packages/shared/forks/ReactFeatureFlags.test-renderer.native-fb.js

@@ -77,7 +77,6 @@ export const passChildrenWhenCloningPersistedNodes = false;
 export const enableUseDeferredValueInitialArg = __EXPERIMENTAL__;
 export const disableClientCache = true;
 
-export const enableServerComponentKeys = true;
 export const enableServerComponentLogs = true;
 
 export const enableRefAsProp = true;

packages/shared/forks/ReactFeatureFlags.test-renderer.www.js

@@ -76,7 +76,6 @@ export const passChildrenWhenCloningPersistedNodes = false;
 export const enableUseDeferredValueInitialArg = true;
 export const disableClientCache = true;
 
-export const enableServerComponentKeys = true;
 export const enableServerComponentLogs = true;
 export const enableInfiniteRenderLoopDetection = false;
 

packages/shared/forks/ReactFeatureFlags.www.js

@@ -109,7 +109,6 @@ export const passChildrenWhenCloningPersistedNodes = false;
 export const enableAsyncDebugInfo = false;
 export const disableClientCache = true;
 
-export const enableServerComponentKeys = true;
 export const enableServerComponentLogs = true;
 
 export const enableReactTestRendererWarning = false;