fix: patch additional methods so React doesnt break with template elements

packages/@react-aria/collections/src/Hidden.tsx

@@ -11,15 +11,21 @@
  */
 
 import {forwardRefType} from '@react-types/shared';
-import React, {Context, createContext, forwardRef, JSX, ReactElement, ReactNode, useContext} from 'react';
+import React, {Context, createContext, forwardRef, JSX, ReactElement, ReactNode, useContext, useRef} from 'react';
+import {useLayoutEffect} from '@react-aria/utils';
 
 // React doesn't understand the <template> element, which doesn't have children like a normal element.
 // It will throw an error during hydration when it expects the firstChild to contain content rendered
 // on the server, when in reality, the browser will have placed this inside the `content` document fragment.
 // This monkey patches the firstChild property for our special hidden template elements to work around this error.
+// does the same for appendChild/removeChild/insertBefore as per the issue below
 // See https://github.com/facebook/react/issues/19932
 if (typeof HTMLTemplateElement !== 'undefined') {
   const getFirstChild = Object.getOwnPropertyDescriptor(Node.prototype, 'firstChild')!.get!;
+  const originalAppendChild = Object.getOwnPropertyDescriptor(Node.prototype, 'appendChild')!.value!;
+  const originalRemoveChild = Object.getOwnPropertyDescriptor(Node.prototype, 'removeChild')!.value!;
+  const originalInsertBefore = Object.getOwnPropertyDescriptor(Node.prototype, 'insertBefore')!.value!;
+
   Object.defineProperty(HTMLTemplateElement.prototype, 'firstChild', {
     configurable: true,
     enumerable: true,
@@ -31,12 +37,61 @@ if (typeof HTMLTemplateElement !== 'undefined') {
       }
     }
   });
+
+  Object.defineProperty(HTMLTemplateElement.prototype, 'appendChild', {
+    configurable: true,
+    enumerable: true,
+    value: function (node) {
+      if (this.dataset.reactAriaHidden) {
+        return this.content.appendChild(node);
+      } else {
+        return originalAppendChild.call(this, node);
+      }
+    }
+  });
+
+  Object.defineProperty(HTMLTemplateElement.prototype, 'removeChild', {
+    configurable: true,
+    enumerable: true,
+    value: function (node) {
+      if (this.dataset.reactAriaHidden) {
+        return this.content.removeChild(node);
+      } else {
+        return originalRemoveChild.call(this, node);
+      }
+    }
+  });
+
+  Object.defineProperty(HTMLTemplateElement.prototype, 'insertBefore', {
+    configurable: true,
+    enumerable: true,
+    value: function (node, child) {
+      if (this.dataset.reactAriaHidden) {
+        return this.content.insertBefore(node, child);
+      } else {
+        return originalInsertBefore.call(this, node, child);
+      }
+    }
+  });
 }
 
 export const HiddenContext: Context<boolean> = createContext<boolean>(false);
 
 export function Hidden(props: {children: ReactNode}): JSX.Element {
   let isHidden = useContext(HiddenContext);
+  let templateRef = useRef<HTMLTemplateElement>(null);
+  // somehow React might add children to the template and we never hit the reactAriaHidden parts of the above overrides
+  // so we need to move those children into the content of the template since templates can't have direct children
+  useLayoutEffect(() => {
+    let el = templateRef.current;
+    if (!el?.dataset.reactAriaHidden) {
+      return;
+    }
+    while (el.childNodes.length > 0) {
+      el.content.appendChild(el.childNodes[0]);
+    }
+  }, []);
+
   if (isHidden) {
     // Don't hide again if we are already hidden.
     return <>{props.children}</>;
@@ -51,7 +106,7 @@ export function Hidden(props: {children: ReactNode}): JSX.Element {
   // In SSR, portals are not supported by React. Instead, always render into a <template>
   // element, which the browser will never display to the user. In addition, the
   // content is not part of the accessible DOM tree, so it won't affect ids or other accessibility attributes.
-  return <template data-react-aria-hidden>{children}</template>;
+  return <template ref={templateRef} data-react-aria-hidden>{children}</template>;
 }
 
 /** Creates a component that forwards its ref and returns null if it is in a hidden subtree. */

packages/@react-spectrum/s2/test/Combobox.test.tsx

@@ -208,9 +208,8 @@ describe('Combobox', () => {
     let dialog = tree.getByRole('dialog');
     expect(dialog).toBeVisible();
 
-    // Because of the fake DOM we'll see this twice
-    expect(tree.getAllByText('Title here')[1]).toBeVisible();
-    expect(tree.getAllByText('Contents')[1]).toBeVisible();
+    expect(tree.getAllByText('Title here')[0]).toBeVisible();
+    expect(tree.getAllByText('Contents')[0]).toBeVisible();
     warn.mockRestore();
   });
 });

packages/@react-spectrum/s2/test/Picker.test.tsx

@@ -205,9 +205,8 @@ describe('Picker', () => {
     let dialog = tree.getByRole('dialog');
     expect(dialog).toBeVisible();
 
-    // Because of the fake DOM we'll see this twice
-    expect(tree.getAllByText('Title here')[1]).toBeVisible();
-    expect(tree.getAllByText('Contents')[1]).toBeVisible();
+    expect(tree.getAllByText('Title here')[0]).toBeVisible();
+    expect(tree.getAllByText('Contents')[0]).toBeVisible();
     warn.mockRestore();
   });
 });