provide impl for byteLengthOfChunk via config

alunyov · alunyov · commit faa9d19b6149 · 2023-11-17T20:46:18.000-05:00
diff --git a/packages/react-server-dom-fb/src/ReactFlightDOMServerFB.js b/packages/react-server-dom-fb/src/ReactFlightDOMServerFB.js
@@ -8,7 +8,11 @@
  */
 
 import type {ReactClientValue} from 'react-server/src/ReactFlightServer';
-import type {Destination} from 'react-server/src/ReactServerStreamConfig';
+import type {
+  Destination,
+  Chunk,
+  PrecomputedChunk,
+} from 'react-server/src/ReactServerStreamConfig';
 import type {ClientManifest} from './ReactFlightReferencesFB';
 
 import {
@@ -17,6 +21,8 @@ import {
   startFlowing,
 } from 'react-server/src/ReactFlightServer';
 
+import {setByteLengthOfChunkImplementation} from 'react-server/src/ReactServerStreamConfig';
+
 export {
   registerClientReference,
   registerServerReference,
@@ -34,6 +40,11 @@ function renderToDestination(
   bundlerConfig: ClientManifest,
   options?: Options,
 ): void {
+  if (!configured) {
+    throw new Error(
+      'Please make sure to call `setConfig(...)` before calling `renderToDestination`.',
+    );
+  }
   const request = createRequest(
     model,
     bundlerConfig,
@@ -43,4 +54,15 @@ function renderToDestination(
   startFlowing(request, destination);
 }
 
-export {renderToDestination};
+type Config = {
+  byteLength: (chunk: Chunk | PrecomputedChunk) => number,
+};
+
+let configured = false;
+
+function setConfig(config: Config): void {
+  setByteLengthOfChunkImplementation(config.byteLength);
+  configured = true;
+}
+
+export {renderToDestination, setConfig};
diff --git a/packages/react-server-dom-fb/src/__tests__/ReactFlightDOMServerFB-test.internal.js b/packages/react-server-dom-fb/src/__tests__/ReactFlightDOMServerFB-test.internal.js
@@ -89,6 +89,9 @@ describe('ReactFlightDOM for FB', () => {
     };
 
     ReactServerDOMServer = require('../ReactFlightDOMServerFB');
+    ReactServerDOMServer.setConfig({
+      byteLength: str => Buffer.byteLength(str),
+    });
 
     // This reset is to load modules for the SSR/Browser scope.
     jest.resetModules();
diff --git a/packages/react-server/src/forks/ReactServerStreamConfig.dom-fb-experimental.js b/packages/react-server/src/forks/ReactServerStreamConfig.dom-fb-experimental.js
@@ -15,45 +15,24 @@ import type {
   BinaryChunk,
 } from '../ReactServerStreamConfigFB';
 
+let byteLengthImpl: null | ((chunk: Chunk | PrecomputedChunk) => number) = null;
+
+export function setByteLengthOfChunkImplementation(
+  impl: (chunk: Chunk | PrecomputedChunk) => number,
+): void {
+  byteLengthImpl = impl;
+}
+
 export function byteLengthOfChunk(chunk: Chunk | PrecomputedChunk): number {
-  if (typeof chunk !== 'string') {
+  if (byteLengthImpl == null) {
     // eslint-disable-next-line react-internal/prod-error-codes
-    throw new Error('byteLengthOfChunk: binary chunks are not supported.');
+    throw new Error(
+      'byteLengthOfChunk implementation is not configured. Please, provide the implementation via ReactFlightDOMServer.setConfig(...);',
+    );
   }
   return byteLengthImpl(chunk);
 }
 
-// TODO: We need to replace this with native implementation, once its available on Hermes
-function byteLengthImpl(chunk: string) {
-  /**
-  From: https://datatracker.ietf.org/doc/html/rfc3629
-  Char. number range  |        UTF-8 octet sequence
-      (hexadecimal)    |              (binary)
-   --------------------+---------------------------------------------
-   0000 0000-0000 007F | 0xxxxxxx
-   0000 0080-0000 07FF | 110xxxxx 10xxxxxx
-   0000 0800-0000 FFFF | 1110xxxx 10xxxxxx 10xxxxxx
-   0001 0000-0010 FFFF | 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
- */
-  let byteLength = chunk.length;
-  for (let i = chunk.length - 1; i >= 0; i--) {
-    const code = chunk.charCodeAt(i);
-    if (code > 0x7f && code <= 0x7ff) {
-      byteLength++;
-    } else if (code > 0x7ff && code <= 0xffff) {
-      byteLength += 2;
-    }
-    if (code >= 0xdc00 && code <= 0xdfff) {
-      // It is a trail surrogate character.
-      // In this case, the code decrements the loop counter i so
-      // that the previous character (which should be a lead surrogate character)
-      // is also included in the calculation.
-      i--;
-    }
-  }
-  return byteLength;
-}
-
 export interface Destination {
   beginWriting(): void;
   write(chunk: Chunk | PrecomputedChunk | BinaryChunk): void;
