fixed unfound node error when Suspense is filtered (#20019)

* fixed unfound node error when Suspense is filtered

* added a test for filtered Suspense node

packages/react-devtools-shared/src/__tests__/__snapshots__/storeComponentFilters-test.js.snap

@@ -97,6 +97,13 @@ exports[`Store component filters should not break when Suspense nodes are filter
       <Component>
 `;
 
+exports[`Store component filters should not break when Suspense nodes are filtered from the tree: 3: suspended 1`] = `
+[root]
+  ▾ <Wrapper>
+    ▾ <Loading>
+        <div>
+`;
+
 exports[`Store component filters should support filtering by element type: 1: mount 1`] = `
 [root]
   ▾ <Root>

packages/react-devtools-shared/src/__tests__/storeComponentFilters-test.js

@@ -256,5 +256,8 @@ describe('Store component filters', () => {
 
     act(() => ReactDOM.render(<Wrapper shouldSuspend={false} />, container));
     expect(store).toMatchSnapshot('2: resolved');
+
+    act(() => ReactDOM.render(<Wrapper shouldSuspend={true} />, container));
+    expect(store).toMatchSnapshot('3: suspended');
   });
 });

packages/react-devtools-shared/src/backend/renderer.js

@@ -1437,6 +1437,9 @@ export function attach(
   }
 
   function recordResetChildren(fiber: Fiber, childSet: Fiber) {
+    if (__DEBUG__) {
+      debug('recordResetChildren()', childSet, fiber);
+    }
     // The frontend only really cares about the displayName, key, and children.
     // The first two don't really change, so we are only concerned with the order of children here.
     // This is trickier than a simple comparison though, since certain types of fibers are filtered.
@@ -1471,6 +1474,23 @@ export function attach(
       nextChildren.push(getFiberID(getPrimaryFiber(fiber)));
     } else {
       let child = fiber.child;
+      const isTimedOutSuspense =
+        fiber.tag === SuspenseComponent && fiber.memoizedState !== null;
+      if (isTimedOutSuspense) {
+        // Special case: if Suspense mounts in a timed-out state,
+        // get the fallback child from the inner fragment,
+        // and skip over the primary child.
+        const primaryChildFragment = fiber.child;
+        const fallbackChildFragment = primaryChildFragment
+          ? primaryChildFragment.sibling
+          : null;
+        const fallbackChild = fallbackChildFragment
+          ? fallbackChildFragment.child
+          : null;
+        if (fallbackChild !== null) {
+          child = fallbackChild;
+        }
+      }
       while (child !== null) {
         findReorderedChildrenRecursively(child, nextChildren);
         child = child.sibling;
@@ -1592,7 +1612,7 @@ export function attach(
       if (nextFallbackChildSet != null) {
         mountFiberRecursively(
           nextFallbackChildSet,
-          nextFiber,
+          shouldIncludeInTree ? nextFiber : parentFiber,
           true,
           traceNearestHostComponentUpdate,
         );