[Float] Don't preload images inside <noscript> (#28815)

gnoff · rickhanlonii · commit deccced2f7a0 · 2024-04-11T13:34:09.000-07:00
`<noscript>` scopes should be considered inert from the perspective of Fizz since we assume they'll only be used in rare and adverse circumstances. When we added preload support for img tags we did not include the noscript scope check in the opt-out for preloading. This change adds it in fixes: #27910
diff --git a/packages/react-dom-bindings/src/server/ReactFizzConfigDOM.js b/packages/react-dom-bindings/src/server/ReactFizzConfigDOM.js
@@ -2762,7 +2762,7 @@ function pushImg(
   props: Object,
   resumableState: ResumableState,
   renderState: RenderState,
-  pictureTagInScope: boolean,
+  pictureOrNoScriptTagInScope: boolean,
 ): null {
   const {src, srcSet} = props;
   if (
@@ -2771,7 +2771,7 @@ function pushImg(
     (typeof src === 'string' || src == null) &&
     (typeof srcSet === 'string' || srcSet == null) &&
     props.fetchPriority !== 'low' &&
-    pictureTagInScope === false &&
+    pictureOrNoScriptTagInScope === false &&
     // We exclude data URIs in src and srcSet since these should not be preloaded
     !(
       typeof src === 'string' &&
@@ -3599,7 +3599,7 @@ export function pushStartInstance(
         props,
         resumableState,
         renderState,
-        !!(formatContext.tagScope & PICTURE_SCOPE),
+        !!(formatContext.tagScope & (PICTURE_SCOPE | NOSCRIPT_SCOPE)),
       );
     }
     // Omitted close tags
diff --git a/packages/react-dom/src/__tests__/ReactDOMFloat-test.js b/packages/react-dom/src/__tests__/ReactDOMFloat-test.js
@@ -4261,6 +4261,38 @@ body {
     );
   });
 
+  // Fixes: https://github.com/facebook/react/issues/27910
+  it('omits preloads for images inside noscript tags', async () => {
+    function App() {
+      return (
+        <html>
+          <body>
+            <img src="foo" />
+            <noscript>
+              <img src="bar" />
+            </noscript>
+          </body>
+        </html>
+      );
+    }
+
+    await act(() => {
+      renderToPipeableStream(<App />).pipe(writable);
+    });
+
+    expect(getMeaningfulChildren(document)).toEqual(
+      <html>
+        <head>
+          <link rel="preload" href="foo" as="image" />
+        </head>
+        <body>
+          <img src="foo" />
+          <noscript>&lt;img src="bar"&gt;</noscript>
+        </body>
+      </html>,
+    );
+  });
+
   it('should handle media on image preload', async () => {
     function App({isClient}) {
       ReactDOM.preload('/server', {
