Unify serverAct helpers (facebook#33327)

This uses the richer `serverAct` helper that we already use in other
tests.

This avoids using the `Scheduler`. We don't use that package on the
server so it doesn't make sense to simulate going through it.
Additionally, we really should be getting rid of it on the client too to
favor `postTask` polyfills.

Author: sebmarkbage

packages/internal-test-utils/internalAct.js

@@ -138,6 +138,7 @@ export async function act<T>(scope: () => Thenable<T>): Thenable<T> {
           // those will also fire now, too, which is not ideal. (The public
           // version of `act` doesn't do this.) For this reason, we should try
           // to avoid using timers in our internal tests.
+          j.runAllTicks();
           j.runOnlyPendingTimers();
           // If a committing a fallback triggers another update, it might not
           // get scheduled until a microtask. So wait one more time.
@@ -194,6 +195,39 @@ export async function act<T>(scope: () => Thenable<T>): Thenable<T> {
   }
 }
 
+async function waitForTasksAndTimers(error: Error) {
+  do {
+    // Wait until end of current task/microtask.
+    await waitForMicrotasks();
+
+    // $FlowFixMe[cannot-resolve-name]: Flow doesn't know about global Jest object
+    if (jest.isEnvironmentTornDown()) {
+      error.message =
+        'The Jest environment was torn down before `act` completed. This ' +
+        'probably means you forgot to `await` an `act` call.';
+      throw error;
+    }
+
+    // $FlowFixMe[cannot-resolve-name]: Flow doesn't know about global Jest object
+    const j = jest;
+    if (j.getTimerCount() > 0) {
+      // There's a pending timer. Flush it now. We only do this in order to
+      // force Suspense fallbacks to display; the fact that it's a timer
+      // is an implementation detail. If there are other timers scheduled,
+      // those will also fire now, too, which is not ideal. (The public
+      // version of `act` doesn't do this.) For this reason, we should try
+      // to avoid using timers in our internal tests.
+      j.runAllTicks();
+      j.runOnlyPendingTimers();
+      // If a committing a fallback triggers another update, it might not
+      // get scheduled until a microtask. So wait one more time.
+      await waitForMicrotasks();
+    } else {
+      break;
+    }
+  } while (true);
+}
+
 export async function serverAct<T>(scope: () => Thenable<T>): Thenable<T> {
   // We require every `act` call to assert console logs
   // with one of the assertion helpers. Fails if not empty.
@@ -233,37 +267,17 @@ export async function serverAct<T>(scope: () => Thenable<T>): Thenable<T> {
   }
 
   try {
-    const result = await scope();
-
-    do {
-      // Wait until end of current task/microtask.
-      await waitForMicrotasks();
-
-      // $FlowFixMe[cannot-resolve-name]: Flow doesn't know about global Jest object
-      if (jest.isEnvironmentTornDown()) {
-        error.message =
-          'The Jest environment was torn down before `act` completed. This ' +
-          'probably means you forgot to `await` an `act` call.';
-        throw error;
-      }
-
-      // $FlowFixMe[cannot-resolve-name]: Flow doesn't know about global Jest object
-      const j = jest;
-      if (j.getTimerCount() > 0) {
-        // There's a pending timer. Flush it now. We only do this in order to
-        // force Suspense fallbacks to display; the fact that it's a timer
-        // is an implementation detail. If there are other timers scheduled,
-        // those will also fire now, too, which is not ideal. (The public
-        // version of `act` doesn't do this.) For this reason, we should try
-        // to avoid using timers in our internal tests.
-        j.runOnlyPendingTimers();
-        // If a committing a fallback triggers another update, it might not
-        // get scheduled until a microtask. So wait one more time.
-        await waitForMicrotasks();
-      } else {
-        break;
-      }
-    } while (true);
+    const promise = scope();
+    // $FlowFixMe[prop-missing]
+    if (promise && typeof promise.catch === 'function') {
+      // $FlowFixMe[incompatible-use]
+      promise.catch(() => {}); // Handle below
+    }
+    // See if we need to do some work to unblock the promise first.
+    await waitForTasksAndTimers(error);
+    const result = await promise;
+    // Then wait to flush the result.
+    await waitForTasksAndTimers(error);
 
     if (thrownErrors.length > 0) {
       // Rethrow any errors logged by the global error handling.

packages/react-dom/src/__tests__/ReactClassComponentPropResolutionFizz-test.js

@@ -22,18 +22,18 @@ let ReactDOMServer;
 let Scheduler;
 let assertLog;
 let container;
-let act;
+let serverAct;
 
 describe('ReactClassComponentPropResolutionFizz', () => {
   beforeEach(() => {
     jest.resetModules();
     Scheduler = require('scheduler');
-    patchMessageChannel(Scheduler);
-    act = require('internal-test-utils').act;
+    patchMessageChannel();
 
     React = require('react');
     ReactDOMServer = require('react-dom/server.browser');
     assertLog = require('internal-test-utils').assertLog;
+    serverAct = require('internal-test-utils').serverAct;
     container = document.createElement('div');
     document.body.appendChild(container);
   });
@@ -42,17 +42,6 @@ describe('ReactClassComponentPropResolutionFizz', () => {
     document.body.removeChild(container);
   });
 
-  async function serverAct(callback) {
-    let maybePromise;
-    await act(() => {
-      maybePromise = callback();
-      if (maybePromise && typeof maybePromise.catch === 'function') {
-        maybePromise.catch(() => {});
-      }
-    });
-    return maybePromise;
-  }
-
   async function readIntoContainer(stream) {
     const reader = stream.getReader();
     let result = '';

packages/react-dom/src/__tests__/ReactDOMFizzDeferredValue-test.js

@@ -21,6 +21,7 @@ global.ReadableStream =
 global.TextEncoder = require('util').TextEncoder;
 
 let act;
+let serverAct;
 let assertLog;
 let waitForPaint;
 let container;
@@ -35,8 +36,9 @@ describe('ReactDOMFizzForm', () => {
   beforeEach(() => {
     jest.resetModules();
     Scheduler = require('scheduler');
-    patchMessageChannel(Scheduler);
+    patchMessageChannel();
     act = require('internal-test-utils').act;
+    serverAct = require('internal-test-utils').serverAct;
     React = require('react');
     ReactDOMServer = require('react-dom/server.browser');
     ReactDOMClient = require('react-dom/client');
@@ -52,17 +54,6 @@ describe('ReactDOMFizzForm', () => {
     document.body.removeChild(container);
   });
 
-  async function serverAct(callback) {
-    let maybePromise;
-    await act(() => {
-      maybePromise = callback();
-      if (maybePromise && typeof maybePromise.catch === 'function') {
-        maybePromise.catch(() => {});
-      }
-    });
-    return maybePromise;
-  }
-
   async function readIntoContainer(stream) {
     const reader = stream.getReader();
     let result = '';

packages/react-dom/src/__tests__/ReactDOMFizzForm-test.js

@@ -18,27 +18,27 @@ global.ReadableStream =
 global.TextEncoder = require('util').TextEncoder;
 
 let act;
+let serverAct;
 let container;
 let React;
 let ReactDOMServer;
 let ReactDOMClient;
 let useFormStatus;
 let useOptimistic;
 let useActionState;
-let Scheduler;
 let assertConsoleErrorDev;
 
 describe('ReactDOMFizzForm', () => {
   beforeEach(() => {
     jest.resetModules();
-    Scheduler = require('scheduler');
-    patchMessageChannel(Scheduler);
+    patchMessageChannel();
     React = require('react');
     ReactDOMServer = require('react-dom/server.browser');
     ReactDOMClient = require('react-dom/client');
     useFormStatus = require('react-dom').useFormStatus;
     useOptimistic = require('react').useOptimistic;
     act = require('internal-test-utils').act;
+    serverAct = require('internal-test-utils').serverAct;
     assertConsoleErrorDev =
       require('internal-test-utils').assertConsoleErrorDev;
     container = document.createElement('div');
@@ -55,14 +55,6 @@ describe('ReactDOMFizzForm', () => {
     document.body.removeChild(container);
   });
 
-  async function serverAct(callback) {
-    let maybePromise;
-    await act(() => {
-      maybePromise = callback();
-    });
-    return maybePromise;
-  }
-
   function submit(submitter) {
     const form = submitter.form || submitter;
     if (!submitter.form) {

packages/react-dom/src/__tests__/ReactDOMFizzServerBrowser-test.js

@@ -19,33 +19,20 @@ global.TextEncoder = require('util').TextEncoder;
 let React;
 let ReactDOMFizzServer;
 let Suspense;
-let Scheduler;
-let act;
+let serverAct;
 
 describe('ReactDOMFizzServerBrowser', () => {
   beforeEach(() => {
     jest.resetModules();
 
-    Scheduler = require('scheduler');
-    patchMessageChannel(Scheduler);
-    act = require('internal-test-utils').act;
+    patchMessageChannel();
+    serverAct = require('internal-test-utils').serverAct;
 
     React = require('react');
     ReactDOMFizzServer = require('react-dom/server.browser');
     Suspense = React.Suspense;
   });
 
-  async function serverAct(callback) {
-    let maybePromise;
-    await act(() => {
-      maybePromise = callback();
-      if (maybePromise && typeof maybePromise.catch === 'function') {
-        maybePromise.catch(() => {});
-      }
-    });
-    return maybePromise;
-  }
-
   const theError = new Error('This is an error');
   function Throw() {
     throw theError;

packages/react-dom/src/__tests__/ReactDOMFizzStaticBrowser-test.js

@@ -31,8 +31,7 @@ let ReactDOMFizzStatic;
 let Suspense;
 let SuspenseList;
 let container;
-let Scheduler;
-let act;
+let serverAct;
 
 describe('ReactDOMFizzStaticBrowser', () => {
   beforeEach(() => {
@@ -42,9 +41,8 @@ describe('ReactDOMFizzStaticBrowser', () => {
     // We need the mocked version of setTimeout inside the document.
     window.setTimeout = setTimeout;
 
-    Scheduler = require('scheduler');
-    patchMessageChannel(Scheduler);
-    act = require('internal-test-utils').act;
+    patchMessageChannel();
+    serverAct = require('internal-test-utils').serverAct;
 
     React = require('react');
     ReactDOM = require('react-dom');
@@ -63,17 +61,6 @@ describe('ReactDOMFizzStaticBrowser', () => {
     document.body.removeChild(container);
   });
 
-  async function serverAct(callback) {
-    let maybePromise;
-    await act(() => {
-      maybePromise = callback();
-      if (maybePromise && typeof maybePromise.catch === 'function') {
-        maybePromise.catch(() => {});
-      }
-    });
-    return maybePromise;
-  }
-
   const theError = new Error('This is an error');
   function Throw() {
     throw theError;

packages/react-dom/src/__tests__/ReactDOMFizzStaticFloat-test.js

@@ -27,15 +27,15 @@ let ReactDOMFizzServer;
 let ReactDOMFizzStatic;
 let Suspense;
 let container;
-let Scheduler;
 let act;
+let serverAct;
 
 describe('ReactDOMFizzStaticFloat', () => {
   beforeEach(() => {
     jest.resetModules();
-    Scheduler = require('scheduler');
-    patchMessageChannel(Scheduler);
+    patchMessageChannel();
     act = require('internal-test-utils').act;
+    serverAct = require('internal-test-utils').serverAct;
 
     React = require('react');
     ReactDOM = require('react-dom');
@@ -52,17 +52,6 @@ describe('ReactDOMFizzStaticFloat', () => {
     document.body.removeChild(container);
   });
 
-  async function serverAct(callback) {
-    let maybePromise;
-    await act(() => {
-      maybePromise = callback();
-      if (maybePromise && typeof maybePromise.catch === 'function') {
-        maybePromise.catch(() => {});
-      }
-    });
-    return maybePromise;
-  }
-
   async function readIntoContainer(stream) {
     const reader = stream.getReader();
     let result = '';

packages/react-dom/src/test-utils/FizzTestUtils.js

@@ -167,7 +167,10 @@ function getVisibleChildren(element: Element): React$Node {
           }
           props[attributes[i].name] = attributes[i].value;
         }
-        props.children = getVisibleChildren(node);
+        const nestedChildren = getVisibleChildren(node);
+        if (nestedChildren !== undefined) {
+          props.children = nestedChildren;
+        }
         children.push(
           require('react').createElement(node.tagName.toLowerCase(), props),
         );

packages/react-server-dom-turbopack/src/__tests__/ReactFlightTurbopackDOM-test.js

@@ -18,6 +18,7 @@ global.TextEncoder = require('util').TextEncoder;
 global.TextDecoder = require('util').TextDecoder;
 
 let act;
+let serverAct;
 let use;
 let clientExports;
 let clientExportsESM;
@@ -28,8 +29,6 @@ let ReactDOMClient;
 let ReactServerDOMServer;
 let ReactServerDOMClient;
 let Suspense;
-let ReactServerScheduler;
-let reactServerAct;
 let ErrorBoundary;
 
 describe('ReactFlightTurbopackDOM', () => {
@@ -39,9 +38,8 @@ describe('ReactFlightTurbopackDOM', () => {
     // condition
     jest.resetModules();
 
-    ReactServerScheduler = require('scheduler');
-    patchSetImmediate(ReactServerScheduler);
-    reactServerAct = require('internal-test-utils').act;
+    patchSetImmediate();
+    serverAct = require('internal-test-utils').serverAct;
 
     // Simulate the condition resolution
     jest.mock('react-server-dom-turbopack/server', () =>
@@ -84,17 +82,6 @@ describe('ReactFlightTurbopackDOM', () => {
     };
   });
 
-  async function serverAct(callback) {
-    let maybePromise;
-    await reactServerAct(() => {
-      maybePromise = callback();
-      if (maybePromise && typeof maybePromise.catch === 'function') {
-        maybePromise.catch(() => {});
-      }
-    });
-    return maybePromise;
-  }
-
   function getTestStream() {
     const writable = new Stream.PassThrough();
     const readable = new ReadableStream({