remove more decoder

vercel · Mar 18, 2024 · c34c21e · c34c21e
1 parent a47aa8a
commit c34c21e
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Showing 3 changed files with 30 additions and 14 deletions.
diff --git a/packages/next/src/server/stream-utils/encodedTags.ts b/packages/next/src/server/stream-utils/encodedTags.ts
@@ -1,5 +1,11 @@
 export const ENCODED_TAGS = {
-  OPENING: {},
+  // opening tags do not have the closing `>` since they can contain other attributes such as `<body className=''>`
+  OPENING: {
+    // <html
+    HTML: new Uint8Array([60, 104, 116, 109, 108]),
+    // <body
+    BODY: new Uint8Array([60, 98, 111, 100, 121]),
+  },
   CLOSED: {
     // </head>
     HEAD: new Uint8Array([60, 47, 104, 101, 97, 100, 62]),

diff --git a/packages/next/src/server/stream-utils/node-web-streams-helper.ts b/packages/next/src/server/stream-utils/node-web-streams-helper.ts
@@ -4,6 +4,7 @@ import { DetachedPromise } from '../../lib/detached-promise'
 import { scheduleImmediate, atLeastOneTask } from '../../lib/scheduler'
 import { ENCODED_TAGS } from './encodedTags'
 import {
+  concatUint8Arrays,
   indexOfUint8Array,
   isEquivalentUint8Arrays,
   removeFromUint8Array,
@@ -444,31 +445,28 @@ export function createRootLayoutValidatorStream(): TransformStream<
   let foundHtml = false
   let foundBody = false
 
-  const decoder = new TextDecoder()
-
-  let content = ''
+  let content = new Uint8Array(0)
   return new TransformStream({
     async transform(chunk, controller) {
+      content = concatUint8Arrays(content, chunk)
       // Peek into the streamed chunk to see if the tags are present.
       if (!foundHtml || !foundBody) {
-        content += decoder.decode(chunk, { stream: true })
-        if (!foundHtml && content.includes('<html')) {
+        if (
+          !foundHtml &&
+          indexOfUint8Array(content, ENCODED_TAGS.OPENING.HTML)
+        ) {
           foundHtml = true
         }
-        if (!foundBody && content.includes('<body')) {
+        if (
+          !foundBody &&
+          indexOfUint8Array(content, ENCODED_TAGS.OPENING.BODY)
+        ) {
           foundBody = true
         }
       }
       controller.enqueue(chunk)
     },
     flush(controller) {
-      // Flush the decoder.
-      if (!foundHtml || !foundBody) {
-        content += decoder.decode()
-        if (!foundHtml && content.includes('<html')) foundHtml = true
-        if (!foundBody && content.includes('<body')) foundBody = true
-      }
-
       const missingTags: typeof window.__next_root_layout_missing_tags = []
       if (!foundHtml) missingTags.push('html')
       if (!foundBody) missingTags.push('body')

diff --git a/packages/next/src/server/stream-utils/uint8array-helpers.ts b/packages/next/src/server/stream-utils/uint8array-helpers.ts
@@ -49,3 +49,15 @@ export function removeFromUint8Array(a: Uint8Array, b: Uint8Array) {
     return a
   }
 }
+
+/**
+ * Combines two Uint8Arrays together in order.
+ *
+ * `(a, b)` will be returned as `a + b`
+ */
+export function concatUint8Arrays(a: Uint8Array, b: Uint8Array) {
+  const result = new Uint8Array(a.length + b.length)
+  result.set(a)
+  result.set(b, a.length)
+  return result
+}