Bug fix when resolving cache

packages/react-server/src/ReactFlightCache.js

@@ -32,21 +32,23 @@ function resolveCache(): Map<Function, mixed> {
 
 export const DefaultCacheDispatcher: CacheDispatcher = {
  getCacheSignal(): AbortSignal {
- let entry: AbortSignal | void = (resolveCache().get(createSignal): any);
+ const cache = resolveCache();
+ let entry: AbortSignal | void = (cache.get(createSignal): any);
  if (entry === undefined) {
  entry = createSignal();
  // $FlowFixMe[incompatible-use] found when upgrading Flow
- currentCache.set(createSignal, entry);
+ cache.set(createSignal, entry);
  }
  return entry;
  },
  getCacheForType<T>(resourceType: () => T): T {
- let entry: T | void = (resolveCache().get(resourceType): any);
+ const cache = resolveCache();
+ let entry: T | void = (cache.get(resourceType): any);
  if (entry === undefined) {
  entry = resourceType();
  // TODO: Warn if undefined?
  // $FlowFixMe[incompatible-use] found when upgrading Flow
- currentCache.set(resourceType, entry);
+ cache.set(resourceType, entry);
  }
  return entry;
  },

packages/react/src/__tests__/ReactFetch-test.js

@@ -36,6 +36,7 @@ let React;
 let ReactServerDOMServer;
 let ReactServerDOMClient;
 let use;
+let cache;
 
 describe('ReactFetch', () => {
  beforeEach(() => {
@@ -50,6 +51,7 @@ describe('ReactFetch', () => {
  ReactServerDOMServer = require('react-server-dom-webpack/server.browser');
  ReactServerDOMClient = require('react-server-dom-webpack/client');
  use = React.experimental_use;
+ cache = React.experimental_cache;
  });
 
  async function render(Component) {
@@ -96,6 +98,27 @@ describe('ReactFetch', () => {
  expect(fetchCount).toBe(2);
  });
 
+ // @gate enableFetchInstrumentation && enableCache
+ it('can dedupe cache in micro tasks', async () => {
+ const cached = cache(async () => {
+ fetchCount++;
+ return 'world';
+ });
+ async function getData() {
+ const r1 = await fetch('hello');
+ const t1 = await r1.text();
+ const t2 = await cached();
+ return t1 + ' ' + t2;
+ }
+ function Component() {
+ return use(getData());
+ }
+ expect(await render(Component)).toMatchInlineSnapshot(
+ `"GET hello [] world"`,
+ );
+ expect(fetchCount).toBe(2);
+ });
+
  // @gate enableFetchInstrumentation && enableCache
  it('can dedupe fetches using Request and not', async () => {
  function Component() {