move the check to updatecontainer, run the act fixtures in ci

fixtures/dom/src/index.test.js

@@ -5,11 +5,11 @@ import TestRenderer from 'react-test-renderer';
 
 let spy;
 beforeEach(() => {
-  spy = jest.spyOn(global.console, 'error');
+  spy = jest.spyOn(console, 'error').mockImplementation(() => {});
 });
 
 function confirmWarning() {
-  expect(spy).toHaveBeenCalledWith(
+  expect(console.error).toHaveBeenCalledWith(
     expect.stringContaining(
       "It looks like you're using the wrong act() around your test interactions."
     ),
@@ -35,6 +35,14 @@ it("doesn't warn when you use the right act + renderer: test", () => {
   expect(spy).not.toHaveBeenCalled();
 });
 
+it('works with createRoot().render combo', () => {
+  const root = ReactDOM.unstable_createRoot(document.createElement('div'));
+  TestRenderer.act(() => {
+    root.render(<App />);
+  });
+  confirmWarning();
+});
+
 it('warns when using the wrong act version - test + dom: render', () => {
   TestRenderer.act(() => {
     TestUtils.renderIntoDocument(<App />);
@@ -56,13 +64,25 @@ it('warns when using the wrong act version - test + dom: updates', () => {
   confirmWarning();
 });
 
-it('warns when using the wrong act version - dom + test: render', () => {
+it('warns when using the wrong act version - dom + test: .create()', () => {
   TestUtils.act(() => {
     TestRenderer.create(<App />);
   });
   confirmWarning();
 });
 
+it('warns when using the wrong act version - dom + test: .update()', () => {
+  let root;
+  // use the right one here so we don't get the first warning
+  TestRenderer.act(() => {
+    root = TestRenderer.create(<App key="one" />);
+  });
+  TestUtils.act(() => {
+    root.update(<App key="two" />);
+  });
+  confirmWarning();
+});
+
 it('warns when using the wrong act version - dom + test: updates', () => {
   let setCtr;
   function Counter(props) {

package.json

@@ -107,6 +107,7 @@
     "test-prod-build": "yarn test-build-prod",
     "test-build": "cross-env NODE_ENV=development jest --config ./scripts/jest/config.build.js",
     "test-build-prod": "cross-env NODE_ENV=production jest --config ./scripts/jest/config.build.js",
+    "test-dom-fixture": "cd fixtures/dom && yarn prestart && yarn test",
     "flow": "node ./scripts/tasks/flow.js",
     "flow-ci": "node ./scripts/tasks/flow-ci.js",
     "prettier": "node ./scripts/prettier/index.js write-changed",

packages/react-reconciler/src/ReactFiberReconciler.js

@@ -277,16 +277,7 @@ export function createContainer(
   isConcurrent: boolean,
   hydrate: boolean,
 ): OpaqueRoot {
-  const fiberRoot = createFiberRoot(containerInfo, isConcurrent, hydrate);
-  if (__DEV__) {
-    // jest isn't a 'global', it's just exposed to tests via a wrapped function
-    // further, this isn't a test file, so flow doesn't recognize the symbol. So...
-    // $FlowExpectedError - because requirements don't give a damn about your type sigs.
-    if ('undefined' !== typeof jest) {
-      warnIfNotScopedWithMatchingAct(fiberRoot.current);
-    }
-  }
-  return fiberRoot;
+  return createFiberRoot(containerInfo, isConcurrent, hydrate);
 }
 
 export function updateContainer(
@@ -298,6 +289,14 @@ export function updateContainer(
   const current = container.current;
   const currentTime = requestCurrentTime();
   const expirationTime = computeExpirationForFiber(currentTime, current);
+  if (__DEV__) {
+    // jest isn't a 'global', it's just exposed to tests via a wrapped function
+    // further, this isn't a test file, so flow doesn't recognize the symbol. So...
+    // $FlowExpectedError - because requirements don't give a damn about your type sigs.
+    if ('undefined' !== typeof jest) {
+      warnIfNotScopedWithMatchingAct(current);
+    }
+  }
   return updateContainerAtExpirationTime(
     element,
     container,

scripts/circleci/test_entry_point.sh

@@ -30,6 +30,7 @@ if [ $((2 % CIRCLE_NODE_TOTAL)) -eq "$CIRCLE_NODE_INDEX" ]; then
   COMMANDS_TO_RUN+=('./scripts/circleci/build.sh')
   COMMANDS_TO_RUN+=('yarn test-build --maxWorkers=2')
   COMMANDS_TO_RUN+=('yarn test-build-prod --maxWorkers=2')
+  COMMANDS_TO_RUN+=('yarn test-dom-fixture')
   COMMANDS_TO_RUN+=('cp ./scripts/rollup/results.json ./build/bundle-sizes.json')
   COMMANDS_TO_RUN+=('node ./scripts/tasks/danger')
   COMMANDS_TO_RUN+=('./scripts/circleci/upload_build.sh')