diff --git a/packages/internal-test-utils/__tests__/ReactInternalTestUtils-test.js b/packages/internal-test-utils/__tests__/ReactInternalTestUtils-test.js
index fa985ef9948af..be98bffe45706 100644
--- a/packages/internal-test-utils/__tests__/ReactInternalTestUtils-test.js
+++ b/packages/internal-test-utils/__tests__/ReactInternalTestUtils-test.js
@@ -161,7 +161,11 @@ describe('ReactInternalTestUtils', () => {
 
     const root = ReactNoop.createRoot();
     await act(() => {
-      root.render(<App />);
+      root.render(
+        <React.StrictMode>
+          <App />
+        </React.StrictMode>
+      );
     });
     assertLog(['A', 'B', 'C']);
   });
diff --git a/packages/react-reconciler/src/__tests__/StrictEffectsMode-test.js b/packages/react-reconciler/src/__tests__/StrictEffectsMode-test.js
index 34ee0b1851613..646638e9ed2d6 100644
--- a/packages/react-reconciler/src/__tests__/StrictEffectsMode-test.js
+++ b/packages/react-reconciler/src/__tests__/StrictEffectsMode-test.js
@@ -11,33 +11,29 @@
 
 let React;
 let ReactNoop;
-let Scheduler;
 let act;
-let assertLog;
 
 describe('StrictEffectsMode', () => {
   beforeEach(() => {
     jest.resetModules();
     act = require('internal-test-utils').act;
-    const InternalTestUtils = require('internal-test-utils');
-    assertLog = InternalTestUtils.assertLog;
 
     React = require('react');
-    Scheduler = require('scheduler');
     ReactNoop = require('react-noop-renderer');
   });
 
   // @gate !disableLegacyMode
   it('should not double invoke effects in legacy mode', async () => {
+    const log = [];
     function App({text}) {
       React.useEffect(() => {
-        Scheduler.log('useEffect mount');
-        return () => Scheduler.log('useEffect unmount');
+        log.push('useEffect mount');
+        return () => log.push('useEffect unmount');
       });
 
       React.useLayoutEffect(() => {
-        Scheduler.log('useLayoutEffect mount');
-        return () => Scheduler.log('useLayoutEffect unmount');
+        log.push('useLayoutEffect mount');
+        return () => log.push('useLayoutEffect unmount');
       });
 
       return text;
@@ -52,19 +48,20 @@ describe('StrictEffectsMode', () => {
       );
     });
 
-    assertLog(['useLayoutEffect mount', 'useEffect mount']);
+    expect(log).toEqual(['useLayoutEffect mount', 'useEffect mount']);
   });
 
   it('double invoking for effects works properly', async () => {
+    const log = [];
     function App({text}) {
       React.useEffect(() => {
-        Scheduler.log('useEffect mount');
-        return () => Scheduler.log('useEffect unmount');
+        log.push('useEffect mount');
+        return () => log.push('useEffect unmount');
       });
 
       React.useLayoutEffect(() => {
-        Scheduler.log('useLayoutEffect mount');
-        return () => Scheduler.log('useLayoutEffect unmount');
+        log.push('useLayoutEffect mount');
+        return () => log.push('useLayoutEffect unmount');
       });
 
       return text;
@@ -80,7 +77,7 @@ describe('StrictEffectsMode', () => {
     });
 
     if (__DEV__) {
-      assertLog([
+      expect(log).toEqual([
         'useLayoutEffect mount',
         'useEffect mount',
         'useLayoutEffect unmount',
@@ -89,9 +86,10 @@ describe('StrictEffectsMode', () => {
         'useEffect mount',
       ]);
     } else {
-      assertLog(['useLayoutEffect mount', 'useEffect mount']);
+      expect(log).toEqual(['useLayoutEffect mount', 'useEffect mount']);
     }
 
+    log.length = 0;
     await act(() => {
       ReactNoop.renderToRootWithID(
         <React.StrictMode>
@@ -101,30 +99,32 @@ describe('StrictEffectsMode', () => {
       );
     });
 
-    assertLog([
+    expect(log).toEqual([
       'useLayoutEffect unmount',
       'useLayoutEffect mount',
       'useEffect unmount',
       'useEffect mount',
     ]);
 
+    log.length = 0;
     await act(() => {
       ReactNoop.unmountRootWithID('root');
     });
 
-    assertLog(['useLayoutEffect unmount', 'useEffect unmount']);
+    expect(log).toEqual(['useLayoutEffect unmount', 'useEffect unmount']);
   });
 
   it('multiple effects are double invoked in the right order (all mounted, all unmounted, all remounted)', async () => {
+    const log = [];
     function App({text}) {
       React.useEffect(() => {
-        Scheduler.log('useEffect One mount');
-        return () => Scheduler.log('useEffect One unmount');
+        log.push('useEffect One mount');
+        return () => log.push('useEffect One unmount');
       });
 
       React.useEffect(() => {
-        Scheduler.log('useEffect Two mount');
-        return () => Scheduler.log('useEffect Two unmount');
+        log.push('useEffect Two mount');
+        return () => log.push('useEffect Two unmount');
       });
 
       return text;
@@ -140,7 +140,7 @@ describe('StrictEffectsMode', () => {
     });
 
     if (__DEV__) {
-      assertLog([
+      expect(log).toEqual([
         'useEffect One mount',
         'useEffect Two mount',
         'useEffect One unmount',
@@ -149,9 +149,10 @@ describe('StrictEffectsMode', () => {
         'useEffect Two mount',
       ]);
     } else {
-      assertLog(['useEffect One mount', 'useEffect Two mount']);
+      expect(log).toEqual(['useEffect One mount', 'useEffect Two mount']);
     }
 
+    log.length = 0;
     await act(() => {
       ReactNoop.renderToRootWithID(
         <React.StrictMode>
@@ -161,30 +162,32 @@ describe('StrictEffectsMode', () => {
       );
     });
 
-    assertLog([
+    expect(log).toEqual([
       'useEffect One unmount',
       'useEffect Two unmount',
       'useEffect One mount',
       'useEffect Two mount',
     ]);
 
+    log.length = 0;
     await act(() => {
       ReactNoop.unmountRootWithID('root');
     });
 
-    assertLog(['useEffect One unmount', 'useEffect Two unmount']);
+    expect(log).toEqual(['useEffect One unmount', 'useEffect Two unmount']);
   });
 
   it('multiple layout effects are double invoked in the right order (all mounted, all unmounted, all remounted)', async () => {
+    const log = [];
     function App({text}) {
       React.useLayoutEffect(() => {
-        Scheduler.log('useLayoutEffect One mount');
-        return () => Scheduler.log('useLayoutEffect One unmount');
+        log.push('useLayoutEffect One mount');
+        return () => log.push('useLayoutEffect One unmount');
       });
 
       React.useLayoutEffect(() => {
-        Scheduler.log('useLayoutEffect Two mount');
-        return () => Scheduler.log('useLayoutEffect Two unmount');
+        log.push('useLayoutEffect Two mount');
+        return () => log.push('useLayoutEffect Two unmount');
       });
 
       return text;
@@ -200,7 +203,7 @@ describe('StrictEffectsMode', () => {
     });
 
     if (__DEV__) {
-      assertLog([
+      expect(log).toEqual([
         'useLayoutEffect One mount',
         'useLayoutEffect Two mount',
         'useLayoutEffect One unmount',
@@ -209,9 +212,13 @@ describe('StrictEffectsMode', () => {
         'useLayoutEffect Two mount',
       ]);
     } else {
-      assertLog(['useLayoutEffect One mount', 'useLayoutEffect Two mount']);
+      expect(log).toEqual([
+        'useLayoutEffect One mount',
+        'useLayoutEffect Two mount',
+      ]);
     }
 
+    log.length = 0;
     await act(() => {
       ReactNoop.renderToRootWithID(
         <React.StrictMode>
@@ -221,28 +228,33 @@ describe('StrictEffectsMode', () => {
       );
     });
 
-    assertLog([
+    expect(log).toEqual([
       'useLayoutEffect One unmount',
       'useLayoutEffect Two unmount',
       'useLayoutEffect One mount',
       'useLayoutEffect Two mount',
     ]);
 
+    log.length = 0;
     await act(() => {
       ReactNoop.unmountRootWithID('root');
     });
 
-    assertLog(['useLayoutEffect One unmount', 'useLayoutEffect Two unmount']);
+    expect(log).toEqual([
+      'useLayoutEffect One unmount',
+      'useLayoutEffect Two unmount',
+    ]);
   });
 
   it('useEffect and useLayoutEffect is called twice when there is no unmount', async () => {
+    const log = [];
     function App({text}) {
       React.useEffect(() => {
-        Scheduler.log('useEffect mount');
+        log.push('useEffect mount');
       });
 
       React.useLayoutEffect(() => {
-        Scheduler.log('useLayoutEffect mount');
+        log.push('useLayoutEffect mount');
       });
 
       return text;
@@ -257,16 +269,17 @@ describe('StrictEffectsMode', () => {
     });
 
     if (__DEV__) {
-      assertLog([
+      expect(log).toEqual([
         'useLayoutEffect mount',
         'useEffect mount',
         'useLayoutEffect mount',
         'useEffect mount',
       ]);
     } else {
-      assertLog(['useLayoutEffect mount', 'useEffect mount']);
+      expect(log).toEqual(['useLayoutEffect mount', 'useEffect mount']);
     }
 
+    log.length = 0;
     await act(() => {
       ReactNoop.renderToRootWithID(
         <React.StrictMode>
@@ -275,32 +288,34 @@ describe('StrictEffectsMode', () => {
       );
     });
 
-    assertLog(['useLayoutEffect mount', 'useEffect mount']);
+    expect(log).toEqual(['useLayoutEffect mount', 'useEffect mount']);
 
+    log.length = 0;
     await act(() => {
       ReactNoop.unmountRootWithID('root');
     });
 
-    assertLog([]);
+    expect(log).toEqual([]);
   });
 
   it('passes the right context to class component lifecycles', async () => {
+    const log = [];
     class App extends React.PureComponent {
       test() {}
 
       componentDidMount() {
         this.test();
-        Scheduler.log('componentDidMount');
+        log.push('componentDidMount');
       }
 
       componentDidUpdate() {
         this.test();
-        Scheduler.log('componentDidUpdate');
+        log.push('componentDidUpdate');
       }
 
       componentWillUnmount() {
         this.test();
-        Scheduler.log('componentWillUnmount');
+        log.push('componentWillUnmount');
       }
 
       render() {
@@ -317,28 +332,29 @@ describe('StrictEffectsMode', () => {
     });
 
     if (__DEV__) {
-      assertLog([
+      expect(log).toEqual([
         'componentDidMount',
         'componentWillUnmount',
         'componentDidMount',
       ]);
     } else {
-      assertLog(['componentDidMount']);
+      expect(log).toEqual(['componentDidMount']);
     }
   });
 
   it('double invoking works for class components', async () => {
+    const log = [];
     class App extends React.PureComponent {
       componentDidMount() {
-        Scheduler.log('componentDidMount');
+        log.push('componentDidMount');
       }
 
       componentDidUpdate() {
-        Scheduler.log('componentDidUpdate');
+        log.push('componentDidUpdate');
       }
 
       componentWillUnmount() {
-        Scheduler.log('componentWillUnmount');
+        log.push('componentWillUnmount');
       }
 
       render() {
@@ -356,15 +372,16 @@ describe('StrictEffectsMode', () => {
     });
 
     if (__DEV__) {
-      assertLog([
+      expect(log).toEqual([
         'componentDidMount',
         'componentWillUnmount',
         'componentDidMount',
       ]);
     } else {
-      assertLog(['componentDidMount']);
+      expect(log).toEqual(['componentDidMount']);
     }
 
+    log.length = 0;
     await act(() => {
       ReactNoop.renderToRootWithID(
         <React.StrictMode>
@@ -374,23 +391,25 @@ describe('StrictEffectsMode', () => {
       );
     });
 
-    assertLog(['componentDidUpdate']);
+    expect(log).toEqual(['componentDidUpdate']);
 
+    log.length = 0;
     await act(() => {
       ReactNoop.unmountRootWithID('root');
     });
 
-    assertLog(['componentWillUnmount']);
+    expect(log).toEqual(['componentWillUnmount']);
   });
 
   it('invokes componentWillUnmount for class components without componentDidMount', async () => {
+    const log = [];
     class App extends React.PureComponent {
       componentDidUpdate() {
-        Scheduler.log('componentDidUpdate');
+        log.push('componentDidUpdate');
       }
 
       componentWillUnmount() {
-        Scheduler.log('componentWillUnmount');
+        log.push('componentWillUnmount');
       }
 
       render() {
@@ -408,11 +427,12 @@ describe('StrictEffectsMode', () => {
     });
 
     if (__DEV__) {
-      assertLog(['componentWillUnmount']);
+      expect(log).toEqual(['componentWillUnmount']);
     } else {
-      assertLog([]);
+      expect(log).toEqual([]);
     }
 
+    log.length = 0;
     await act(() => {
       ReactNoop.renderToRootWithID(
         <React.StrictMode>
@@ -422,28 +442,30 @@ describe('StrictEffectsMode', () => {
       );
     });
 
-    assertLog(['componentDidUpdate']);
+    expect(log).toEqual(['componentDidUpdate']);
 
+    log.length = 0;
     await act(() => {
       ReactNoop.unmountRootWithID('root');
     });
 
-    assertLog(['componentWillUnmount']);
+    expect(log).toEqual(['componentWillUnmount']);
   });
 
   // @gate !disableLegacyMode
   it('should not double invoke class lifecycles in legacy mode', async () => {
+    const log = [];
     class App extends React.PureComponent {
       componentDidMount() {
-        Scheduler.log('componentDidMount');
+        log.push('componentDidMount');
       }
 
       componentDidUpdate() {
-        Scheduler.log('componentDidUpdate');
+        log.push('componentDidUpdate');
       }
 
       componentWillUnmount() {
-        Scheduler.log('componentWillUnmount');
+        log.push('componentWillUnmount');
       }
 
       render() {
@@ -460,26 +482,27 @@ describe('StrictEffectsMode', () => {
       );
     });
 
-    assertLog(['componentDidMount']);
+    expect(log).toEqual(['componentDidMount']);
   });
 
   it('double flushing passive effects only results in one double invoke', async () => {
+    const log = [];
     function App({text}) {
       const [state, setState] = React.useState(0);
       React.useEffect(() => {
         if (state !== 1) {
           setState(1);
         }
-        Scheduler.log('useEffect mount');
-        return () => Scheduler.log('useEffect unmount');
+        log.push('useEffect mount');
+        return () => log.push('useEffect unmount');
       });
 
       React.useLayoutEffect(() => {
-        Scheduler.log('useLayoutEffect mount');
-        return () => Scheduler.log('useLayoutEffect unmount');
+        log.push('useLayoutEffect mount');
+        return () => log.push('useLayoutEffect unmount');
       });
 
-      Scheduler.log(text);
+      log.push(text);
       return text;
     }
 
@@ -492,7 +515,8 @@ describe('StrictEffectsMode', () => {
     });
 
     if (__DEV__) {
-      assertLog([
+      expect(log).toEqual([
+        'mount',
         'mount',
         'useLayoutEffect mount',
         'useEffect mount',
@@ -501,13 +525,14 @@ describe('StrictEffectsMode', () => {
         'useLayoutEffect mount',
         'useEffect mount',
         'mount',
+        'mount',
         'useLayoutEffect unmount',
         'useLayoutEffect mount',
         'useEffect unmount',
         'useEffect mount',
       ]);
     } else {
-      assertLog([
+      expect(log).toEqual([
         'mount',
         'useLayoutEffect mount',
         'useEffect mount',
@@ -521,15 +546,16 @@ describe('StrictEffectsMode', () => {
   });
 
   it('newly mounted components after initial mount get double invoked', async () => {
+    const log = [];
     let _setShowChild;
     function Child() {
       React.useEffect(() => {
-        Scheduler.log('Child useEffect mount');
-        return () => Scheduler.log('Child useEffect unmount');
+        log.push('Child useEffect mount');
+        return () => log.push('Child useEffect unmount');
       });
       React.useLayoutEffect(() => {
-        Scheduler.log('Child useLayoutEffect mount');
-        return () => Scheduler.log('Child useLayoutEffect unmount');
+        log.push('Child useLayoutEffect mount');
+        return () => log.push('Child useLayoutEffect unmount');
       });
 
       return null;
@@ -539,12 +565,12 @@ describe('StrictEffectsMode', () => {
       const [showChild, setShowChild] = React.useState(false);
       _setShowChild = setShowChild;
       React.useEffect(() => {
-        Scheduler.log('App useEffect mount');
-        return () => Scheduler.log('App useEffect unmount');
+        log.push('App useEffect mount');
+        return () => log.push('App useEffect unmount');
       });
       React.useLayoutEffect(() => {
-        Scheduler.log('App useLayoutEffect mount');
-        return () => Scheduler.log('App useLayoutEffect unmount');
+        log.push('App useLayoutEffect mount');
+        return () => log.push('App useLayoutEffect unmount');
       });
 
       return showChild && <Child />;
@@ -560,7 +586,7 @@ describe('StrictEffectsMode', () => {
     });
 
     if (__DEV__) {
-      assertLog([
+      expect(log).toEqual([
         'App useLayoutEffect mount',
         'App useEffect mount',
         'App useLayoutEffect unmount',
@@ -569,15 +595,16 @@ describe('StrictEffectsMode', () => {
         'App useEffect mount',
       ]);
     } else {
-      assertLog(['App useLayoutEffect mount', 'App useEffect mount']);
+      expect(log).toEqual(['App useLayoutEffect mount', 'App useEffect mount']);
     }
 
+    log.length = 0;
     await act(() => {
       _setShowChild(true);
     });
 
     if (__DEV__) {
-      assertLog([
+      expect(log).toEqual([
         'App useLayoutEffect unmount',
         'Child useLayoutEffect mount',
         'App useLayoutEffect mount',
@@ -590,7 +617,7 @@ describe('StrictEffectsMode', () => {
         'Child useEffect mount',
       ]);
     } else {
-      assertLog([
+      expect(log).toEqual([
         'App useLayoutEffect unmount',
         'Child useLayoutEffect mount',
         'App useLayoutEffect mount',
@@ -602,13 +629,14 @@ describe('StrictEffectsMode', () => {
   });
 
   it('classes and functions are double invoked together correctly', async () => {
+    const log = [];
     class ClassChild extends React.PureComponent {
       componentDidMount() {
-        Scheduler.log('componentDidMount');
+        log.push('componentDidMount');
       }
 
       componentWillUnmount() {
-        Scheduler.log('componentWillUnmount');
+        log.push('componentWillUnmount');
       }
 
       render() {
@@ -618,12 +646,12 @@ describe('StrictEffectsMode', () => {
 
     function FunctionChild({text}) {
       React.useEffect(() => {
-        Scheduler.log('useEffect mount');
-        return () => Scheduler.log('useEffect unmount');
+        log.push('useEffect mount');
+        return () => log.push('useEffect unmount');
       });
       React.useLayoutEffect(() => {
-        Scheduler.log('useLayoutEffect mount');
-        return () => Scheduler.log('useLayoutEffect unmount');
+        log.push('useLayoutEffect mount');
+        return () => log.push('useLayoutEffect unmount');
       });
       return text;
     }
@@ -647,7 +675,7 @@ describe('StrictEffectsMode', () => {
     });
 
     if (__DEV__) {
-      assertLog([
+      expect(log).toEqual([
         'componentDidMount',
         'useLayoutEffect mount',
         'useEffect mount',
@@ -659,13 +687,14 @@ describe('StrictEffectsMode', () => {
         'useEffect mount',
       ]);
     } else {
-      assertLog([
+      expect(log).toEqual([
         'componentDidMount',
         'useLayoutEffect mount',
         'useEffect mount',
       ]);
     }
 
+    log.length = 0;
     await act(() => {
       ReactNoop.renderToRootWithID(
         <React.StrictMode>
@@ -675,18 +704,19 @@ describe('StrictEffectsMode', () => {
       );
     });
 
-    assertLog([
+    expect(log).toEqual([
       'useLayoutEffect unmount',
       'useLayoutEffect mount',
       'useEffect unmount',
       'useEffect mount',
     ]);
 
+    log.length = 0;
     await act(() => {
       ReactNoop.unmountRootWithID('root');
     });
 
-    assertLog([
+    expect(log).toEqual([
       'componentWillUnmount',
       'useLayoutEffect unmount',
       'useEffect unmount',
@@ -694,9 +724,10 @@ describe('StrictEffectsMode', () => {
   });
 
   it('classes without componentDidMount and functions are double invoked together correctly', async () => {
+    const log = [];
     class ClassChild extends React.PureComponent {
       componentWillUnmount() {
-        Scheduler.log('componentWillUnmount');
+        log.push('componentWillUnmount');
       }
 
       render() {
@@ -706,12 +737,12 @@ describe('StrictEffectsMode', () => {
 
     function FunctionChild({text}) {
       React.useEffect(() => {
-        Scheduler.log('useEffect mount');
-        return () => Scheduler.log('useEffect unmount');
+        log.push('useEffect mount');
+        return () => log.push('useEffect unmount');
       });
       React.useLayoutEffect(() => {
-        Scheduler.log('useLayoutEffect mount');
-        return () => Scheduler.log('useLayoutEffect unmount');
+        log.push('useLayoutEffect mount');
+        return () => log.push('useLayoutEffect unmount');
       });
       return text;
     }
@@ -735,7 +766,7 @@ describe('StrictEffectsMode', () => {
     });
 
     if (__DEV__) {
-      assertLog([
+      expect(log).toEqual([
         'useLayoutEffect mount',
         'useEffect mount',
         'componentWillUnmount',
@@ -745,9 +776,10 @@ describe('StrictEffectsMode', () => {
         'useEffect mount',
       ]);
     } else {
-      assertLog(['useLayoutEffect mount', 'useEffect mount']);
+      expect(log).toEqual(['useLayoutEffect mount', 'useEffect mount']);
     }
 
+    log.length = 0;
     await act(() => {
       ReactNoop.renderToRootWithID(
         <React.StrictMode>
@@ -757,18 +789,19 @@ describe('StrictEffectsMode', () => {
       );
     });
 
-    assertLog([
+    expect(log).toEqual([
       'useLayoutEffect unmount',
       'useLayoutEffect mount',
       'useEffect unmount',
       'useEffect mount',
     ]);
 
+    log.length = 0;
     await act(() => {
       ReactNoop.unmountRootWithID('root');
     });
 
-    assertLog([
+    expect(log).toEqual([
       'componentWillUnmount',
       'useLayoutEffect unmount',
       'useEffect unmount',
@@ -777,7 +810,7 @@ describe('StrictEffectsMode', () => {
 
   // @gate __DEV__
   it('should double invoke effects after a re-suspend', async () => {
-    // Not using Scheduler.log because it silences double render logs.
+    // Not using log.push because it silences double render logs.
     let log = [];
     let shouldSuspend = true;
     let resolve;
diff --git a/packages/react-reconciler/src/__tests__/StrictEffectsModeDefaults-test.internal.js b/packages/react-reconciler/src/__tests__/StrictEffectsModeDefaults-test.internal.js
index ef0f494b687da..7d1a3b77cb543 100644
--- a/packages/react-reconciler/src/__tests__/StrictEffectsModeDefaults-test.internal.js
+++ b/packages/react-reconciler/src/__tests__/StrictEffectsModeDefaults-test.internal.js
@@ -13,7 +13,6 @@ let React;
 let ReactNoop;
 let Scheduler;
 let act;
-let assertLog;
 let waitFor;
 let waitForAll;
 let waitForPaint;
@@ -31,20 +30,20 @@ describe('StrictEffectsMode defaults', () => {
     waitFor = InternalTestUtils.waitFor;
     waitForAll = InternalTestUtils.waitForAll;
     waitForPaint = InternalTestUtils.waitForPaint;
-    assertLog = InternalTestUtils.assertLog;
   });
 
   // @gate !disableLegacyMode
   it('should not double invoke effects in legacy mode', async () => {
+    const log = [];
     function App({text}) {
       React.useEffect(() => {
-        Scheduler.log('useEffect mount');
-        return () => Scheduler.log('useEffect unmount');
+        log.push('useEffect mount');
+        return () => log.push('useEffect unmount');
       });
 
       React.useLayoutEffect(() => {
-        Scheduler.log('useLayoutEffect mount');
-        return () => Scheduler.log('useLayoutEffect unmount');
+        log.push('useLayoutEffect mount');
+        return () => log.push('useLayoutEffect unmount');
       });
 
       return text;
@@ -58,22 +57,23 @@ describe('StrictEffectsMode defaults', () => {
       );
     });
 
-    assertLog(['useLayoutEffect mount', 'useEffect mount']);
+    expect(log).toEqual(['useLayoutEffect mount', 'useEffect mount']);
   });
 
   // @gate !disableLegacyMode
   it('should not double invoke class lifecycles in legacy mode', async () => {
+    const log = [];
     class App extends React.PureComponent {
       componentDidMount() {
-        Scheduler.log('componentDidMount');
+        log.push('componentDidMount');
       }
 
       componentDidUpdate() {
-        Scheduler.log('componentDidUpdate');
+        log.push('componentDidUpdate');
       }
 
       componentWillUnmount() {
-        Scheduler.log('componentWillUnmount');
+        log.push('componentWillUnmount');
       }
 
       render() {
@@ -89,15 +89,20 @@ describe('StrictEffectsMode defaults', () => {
       );
     });
 
-    assertLog(['componentDidMount']);
+    expect(log).toEqual(['componentDidMount']);
   });
 
   if (__DEV__) {
     it('should flush double-invoked effects within the same frame as layout effects if there are no passive effects', async () => {
+      const log = [];
       function ComponentWithEffects({label}) {
         React.useLayoutEffect(() => {
           Scheduler.log(`useLayoutEffect mount "${label}"`);
-          return () => Scheduler.log(`useLayoutEffect unmount "${label}"`);
+          log.push(`useLayoutEffect mount "${label}"`);
+          return () => {
+            Scheduler.log(`useLayoutEffect unmount "${label}"`);
+            log.push(`useLayoutEffect unmount "${label}"`);
+          };
         });
 
         return label;
@@ -115,8 +120,14 @@ describe('StrictEffectsMode defaults', () => {
           'useLayoutEffect unmount "one"',
           'useLayoutEffect mount "one"',
         ]);
+        expect(log).toEqual([
+          'useLayoutEffect mount "one"',
+          'useLayoutEffect unmount "one"',
+          'useLayoutEffect mount "one"',
+        ]);
       });
 
+      log.length = 0;
       await act(async () => {
         ReactNoop.render(
           <React.StrictMode>
@@ -125,13 +136,23 @@ describe('StrictEffectsMode defaults', () => {
           </React.StrictMode>,
         );
 
-        assertLog([]);
+        expect(log).toEqual([]);
         await waitForPaint([
           // Cleanup and re-run "one" (and "two") since there is no dependencies array.
           'useLayoutEffect unmount "one"',
           'useLayoutEffect mount "one"',
           'useLayoutEffect mount "two"',
 
+          // Since "two" is new, it should be double-invoked.
+          'useLayoutEffect unmount "two"',
+          'useLayoutEffect mount "two"',
+        ]);
+        expect(log).toEqual([
+          // Cleanup and re-run "one" (and "two") since there is no dependencies array.
+          'useLayoutEffect unmount "one"',
+          'useLayoutEffect mount "one"',
+          'useLayoutEffect mount "two"',
+
           // Since "two" is new, it should be double-invoked.
           'useLayoutEffect unmount "two"',
           'useLayoutEffect mount "two"',
@@ -142,15 +163,24 @@ describe('StrictEffectsMode defaults', () => {
     // This test also verifies that double-invoked effects flush synchronously
     // within the same frame as passive effects.
     it('should double invoke effects only for newly mounted components', async () => {
+      const log = [];
       function ComponentWithEffects({label}) {
         React.useEffect(() => {
+          log.push(`useEffect mount "${label}"`);
           Scheduler.log(`useEffect mount "${label}"`);
-          return () => Scheduler.log(`useEffect unmount "${label}"`);
+          return () => {
+            log.push(`useEffect unmount "${label}"`);
+            Scheduler.log(`useEffect unmount "${label}"`);
+          };
         });
 
         React.useLayoutEffect(() => {
+          log.push(`useLayoutEffect mount "${label}"`);
           Scheduler.log(`useLayoutEffect mount "${label}"`);
-          return () => Scheduler.log(`useLayoutEffect unmount "${label}"`);
+          return () => {
+            log.push(`useLayoutEffect unmount "${label}"`);
+            Scheduler.log(`useLayoutEffect unmount "${label}"`);
+          };
         });
 
         return label;
@@ -171,8 +201,17 @@ describe('StrictEffectsMode defaults', () => {
           'useLayoutEffect mount "one"',
           'useEffect mount "one"',
         ]);
+        expect(log).toEqual([
+          'useLayoutEffect mount "one"',
+          'useEffect mount "one"',
+          'useLayoutEffect unmount "one"',
+          'useEffect unmount "one"',
+          'useLayoutEffect mount "one"',
+          'useEffect mount "one"',
+        ]);
       });
 
+      log.length = 0;
       await act(async () => {
         ReactNoop.render(
           <React.StrictMode>
@@ -187,11 +226,29 @@ describe('StrictEffectsMode defaults', () => {
           'useLayoutEffect mount "one"',
           'useLayoutEffect mount "two"',
         ]);
+        expect(log).toEqual([
+          // Cleanup and re-run "one" (and "two") since there is no dependencies array.
+          'useLayoutEffect unmount "one"',
+          'useLayoutEffect mount "one"',
+          'useLayoutEffect mount "two"',
+        ]);
+        log.length = 0;
         await waitForAll([
           'useEffect unmount "one"',
           'useEffect mount "one"',
           'useEffect mount "two"',
 
+          // Since "two" is new, it should be double-invoked.
+          'useLayoutEffect unmount "two"',
+          'useEffect unmount "two"',
+          'useLayoutEffect mount "two"',
+          'useEffect mount "two"',
+        ]);
+        expect(log).toEqual([
+          'useEffect unmount "one"',
+          'useEffect mount "one"',
+          'useEffect mount "two"',
+
           // Since "two" is new, it should be double-invoked.
           'useLayoutEffect unmount "two"',
           'useEffect unmount "two"',
@@ -202,15 +259,16 @@ describe('StrictEffectsMode defaults', () => {
     });
 
     it('double invoking for effects for modern roots', async () => {
+      const log = [];
       function App({text}) {
         React.useEffect(() => {
-          Scheduler.log('useEffect mount');
-          return () => Scheduler.log('useEffect unmount');
+          log.push('useEffect mount');
+          return () => log.push('useEffect unmount');
         });
 
         React.useLayoutEffect(() => {
-          Scheduler.log('useLayoutEffect mount');
-          return () => Scheduler.log('useLayoutEffect unmount');
+          log.push('useLayoutEffect mount');
+          return () => log.push('useLayoutEffect unmount');
         });
 
         return text;
@@ -223,7 +281,7 @@ describe('StrictEffectsMode defaults', () => {
         );
       });
 
-      assertLog([
+      expect(log).toEqual([
         'useLayoutEffect mount',
         'useEffect mount',
         'useLayoutEffect unmount',
@@ -232,6 +290,7 @@ describe('StrictEffectsMode defaults', () => {
         'useEffect mount',
       ]);
 
+      log.length = 0;
       await act(() => {
         ReactNoop.render(
           <React.StrictMode>
@@ -240,30 +299,32 @@ describe('StrictEffectsMode defaults', () => {
         );
       });
 
-      assertLog([
+      expect(log).toEqual([
         'useLayoutEffect unmount',
         'useLayoutEffect mount',
         'useEffect unmount',
         'useEffect mount',
       ]);
 
+      log.length = 0;
       await act(() => {
         ReactNoop.render(null);
       });
 
-      assertLog(['useLayoutEffect unmount', 'useEffect unmount']);
+      expect(log).toEqual(['useLayoutEffect unmount', 'useEffect unmount']);
     });
 
     it('multiple effects are double invoked in the right order (all mounted, all unmounted, all remounted)', async () => {
+      const log = [];
       function App({text}) {
         React.useEffect(() => {
-          Scheduler.log('useEffect One mount');
-          return () => Scheduler.log('useEffect One unmount');
+          log.push('useEffect One mount');
+          return () => log.push('useEffect One unmount');
         });
 
         React.useEffect(() => {
-          Scheduler.log('useEffect Two mount');
-          return () => Scheduler.log('useEffect Two unmount');
+          log.push('useEffect Two mount');
+          return () => log.push('useEffect Two unmount');
         });
 
         return text;
@@ -277,7 +338,7 @@ describe('StrictEffectsMode defaults', () => {
         );
       });
 
-      assertLog([
+      expect(log).toEqual([
         'useEffect One mount',
         'useEffect Two mount',
         'useEffect One unmount',
@@ -286,6 +347,7 @@ describe('StrictEffectsMode defaults', () => {
         'useEffect Two mount',
       ]);
 
+      log.length = 0;
       await act(() => {
         ReactNoop.render(
           <React.StrictMode>
@@ -294,30 +356,32 @@ describe('StrictEffectsMode defaults', () => {
         );
       });
 
-      assertLog([
+      expect(log).toEqual([
         'useEffect One unmount',
         'useEffect Two unmount',
         'useEffect One mount',
         'useEffect Two mount',
       ]);
 
+      log.length = 0;
       await act(() => {
         ReactNoop.render(null);
       });
 
-      assertLog(['useEffect One unmount', 'useEffect Two unmount']);
+      expect(log).toEqual(['useEffect One unmount', 'useEffect Two unmount']);
     });
 
     it('multiple layout effects are double invoked in the right order (all mounted, all unmounted, all remounted)', async () => {
+      const log = [];
       function App({text}) {
         React.useLayoutEffect(() => {
-          Scheduler.log('useLayoutEffect One mount');
-          return () => Scheduler.log('useLayoutEffect One unmount');
+          log.push('useLayoutEffect One mount');
+          return () => log.push('useLayoutEffect One unmount');
         });
 
         React.useLayoutEffect(() => {
-          Scheduler.log('useLayoutEffect Two mount');
-          return () => Scheduler.log('useLayoutEffect Two unmount');
+          log.push('useLayoutEffect Two mount');
+          return () => log.push('useLayoutEffect Two unmount');
         });
 
         return text;
@@ -331,7 +395,7 @@ describe('StrictEffectsMode defaults', () => {
         );
       });
 
-      assertLog([
+      expect(log).toEqual([
         'useLayoutEffect One mount',
         'useLayoutEffect Two mount',
         'useLayoutEffect One unmount',
@@ -340,6 +404,7 @@ describe('StrictEffectsMode defaults', () => {
         'useLayoutEffect Two mount',
       ]);
 
+      log.length = 0;
       await act(() => {
         ReactNoop.render(
           <React.StrictMode>
@@ -348,28 +413,33 @@ describe('StrictEffectsMode defaults', () => {
         );
       });
 
-      assertLog([
+      expect(log).toEqual([
         'useLayoutEffect One unmount',
         'useLayoutEffect Two unmount',
         'useLayoutEffect One mount',
         'useLayoutEffect Two mount',
       ]);
 
+      log.length = 0;
       await act(() => {
         ReactNoop.render(null);
       });
 
-      assertLog(['useLayoutEffect One unmount', 'useLayoutEffect Two unmount']);
+      expect(log).toEqual([
+        'useLayoutEffect One unmount',
+        'useLayoutEffect Two unmount',
+      ]);
     });
 
     it('useEffect and useLayoutEffect is called twice when there is no unmount', async () => {
+      const log = [];
       function App({text}) {
         React.useEffect(() => {
-          Scheduler.log('useEffect mount');
+          log.push('useEffect mount');
         });
 
         React.useLayoutEffect(() => {
-          Scheduler.log('useLayoutEffect mount');
+          log.push('useLayoutEffect mount');
         });
 
         return text;
@@ -383,13 +453,14 @@ describe('StrictEffectsMode defaults', () => {
         );
       });
 
-      assertLog([
+      expect(log).toEqual([
         'useLayoutEffect mount',
         'useEffect mount',
         'useLayoutEffect mount',
         'useEffect mount',
       ]);
 
+      log.length = 0;
       await act(() => {
         ReactNoop.render(
           <React.StrictMode>
@@ -398,13 +469,14 @@ describe('StrictEffectsMode defaults', () => {
         );
       });
 
-      assertLog(['useLayoutEffect mount', 'useEffect mount']);
+      expect(log).toEqual(['useLayoutEffect mount', 'useEffect mount']);
 
+      log.length = 0;
       await act(() => {
         ReactNoop.render(null);
       });
 
-      assertLog([]);
+      expect(log).toEqual([]);
     });
 
     //@gate useModernStrictMode
@@ -436,22 +508,23 @@ describe('StrictEffectsMode defaults', () => {
     });
 
     it('passes the right context to class component lifecycles', async () => {
+      const log = [];
       class App extends React.PureComponent {
         test() {}
 
         componentDidMount() {
           this.test();
-          Scheduler.log('componentDidMount');
+          log.push('componentDidMount');
         }
 
         componentDidUpdate() {
           this.test();
-          Scheduler.log('componentDidUpdate');
+          log.push('componentDidUpdate');
         }
 
         componentWillUnmount() {
           this.test();
-          Scheduler.log('componentWillUnmount');
+          log.push('componentWillUnmount');
         }
 
         render() {
@@ -467,7 +540,7 @@ describe('StrictEffectsMode defaults', () => {
         );
       });
 
-      assertLog([
+      expect(log).toEqual([
         'componentDidMount',
         'componentWillUnmount',
         'componentDidMount',
@@ -475,17 +548,18 @@ describe('StrictEffectsMode defaults', () => {
     });
 
     it('double invoking works for class components', async () => {
+      const log = [];
       class App extends React.PureComponent {
         componentDidMount() {
-          Scheduler.log('componentDidMount');
+          log.push('componentDidMount');
         }
 
         componentDidUpdate() {
-          Scheduler.log('componentDidUpdate');
+          log.push('componentDidUpdate');
         }
 
         componentWillUnmount() {
-          Scheduler.log('componentWillUnmount');
+          log.push('componentWillUnmount');
         }
 
         render() {
@@ -501,12 +575,13 @@ describe('StrictEffectsMode defaults', () => {
         );
       });
 
-      assertLog([
+      expect(log).toEqual([
         'componentDidMount',
         'componentWillUnmount',
         'componentDidMount',
       ]);
 
+      log.length = 0;
       await act(() => {
         ReactNoop.render(
           <React.StrictMode>
@@ -515,35 +590,38 @@ describe('StrictEffectsMode defaults', () => {
         );
       });
 
-      assertLog(['componentDidUpdate']);
+      expect(log).toEqual(['componentDidUpdate']);
 
+      log.length = 0;
       await act(() => {
         ReactNoop.render(null);
       });
 
-      assertLog(['componentWillUnmount']);
+      expect(log).toEqual(['componentWillUnmount']);
     });
 
     it('double flushing passive effects only results in one double invoke', async () => {
+      const log = [];
       function App({text}) {
         const [state, setState] = React.useState(0);
         React.useEffect(() => {
           if (state !== 1) {
             setState(1);
           }
-          Scheduler.log('useEffect mount');
-          return () => Scheduler.log('useEffect unmount');
+          log.push('useEffect mount');
+          return () => log.push('useEffect unmount');
         });
 
         React.useLayoutEffect(() => {
-          Scheduler.log('useLayoutEffect mount');
-          return () => Scheduler.log('useLayoutEffect unmount');
+          log.push('useLayoutEffect mount');
+          return () => log.push('useLayoutEffect unmount');
         });
 
-        Scheduler.log(text);
+        log.push(text);
         return text;
       }
 
+      log.length = 0;
       await act(() => {
         ReactNoop.render(
           <React.StrictMode>
@@ -552,7 +630,8 @@ describe('StrictEffectsMode defaults', () => {
         );
       });
 
-      assertLog([
+      expect(log).toEqual([
+        'mount',
         'mount',
         'useLayoutEffect mount',
         'useEffect mount',
@@ -561,6 +640,7 @@ describe('StrictEffectsMode defaults', () => {
         'useLayoutEffect mount',
         'useEffect mount',
         'mount',
+        'mount',
         'useLayoutEffect unmount',
         'useLayoutEffect mount',
         'useEffect unmount',
@@ -570,14 +650,15 @@ describe('StrictEffectsMode defaults', () => {
 
     it('newly mounted components after initial mount get double invoked', async () => {
       let _setShowChild;
+      const log = [];
       function Child() {
         React.useEffect(() => {
-          Scheduler.log('Child useEffect mount');
-          return () => Scheduler.log('Child useEffect unmount');
+          log.push('Child useEffect mount');
+          return () => log.push('Child useEffect unmount');
         });
         React.useLayoutEffect(() => {
-          Scheduler.log('Child useLayoutEffect mount');
-          return () => Scheduler.log('Child useLayoutEffect unmount');
+          log.push('Child useLayoutEffect mount');
+          return () => log.push('Child useLayoutEffect unmount');
         });
 
         return null;
@@ -587,12 +668,12 @@ describe('StrictEffectsMode defaults', () => {
         const [showChild, setShowChild] = React.useState(false);
         _setShowChild = setShowChild;
         React.useEffect(() => {
-          Scheduler.log('App useEffect mount');
-          return () => Scheduler.log('App useEffect unmount');
+          log.push('App useEffect mount');
+          return () => log.push('App useEffect unmount');
         });
         React.useLayoutEffect(() => {
-          Scheduler.log('App useLayoutEffect mount');
-          return () => Scheduler.log('App useLayoutEffect unmount');
+          log.push('App useLayoutEffect mount');
+          return () => log.push('App useLayoutEffect unmount');
         });
 
         return showChild && <Child />;
@@ -606,7 +687,7 @@ describe('StrictEffectsMode defaults', () => {
         );
       });
 
-      assertLog([
+      expect(log).toEqual([
         'App useLayoutEffect mount',
         'App useEffect mount',
         'App useLayoutEffect unmount',
@@ -615,11 +696,12 @@ describe('StrictEffectsMode defaults', () => {
         'App useEffect mount',
       ]);
 
+      log.length = 0;
       await act(() => {
         _setShowChild(true);
       });
 
-      assertLog([
+      expect(log).toEqual([
         'App useLayoutEffect unmount',
         'Child useLayoutEffect mount',
         'App useLayoutEffect mount',
@@ -634,13 +716,14 @@ describe('StrictEffectsMode defaults', () => {
     });
 
     it('classes and functions are double invoked together correctly', async () => {
+      const log = [];
       class ClassChild extends React.PureComponent {
         componentDidMount() {
-          Scheduler.log('componentDidMount');
+          log.push('componentDidMount');
         }
 
         componentWillUnmount() {
-          Scheduler.log('componentWillUnmount');
+          log.push('componentWillUnmount');
         }
 
         render() {
@@ -650,12 +733,12 @@ describe('StrictEffectsMode defaults', () => {
 
       function FunctionChild({text}) {
         React.useEffect(() => {
-          Scheduler.log('useEffect mount');
-          return () => Scheduler.log('useEffect unmount');
+          log.push('useEffect mount');
+          return () => log.push('useEffect unmount');
         });
         React.useLayoutEffect(() => {
-          Scheduler.log('useLayoutEffect mount');
-          return () => Scheduler.log('useLayoutEffect unmount');
+          log.push('useLayoutEffect mount');
+          return () => log.push('useLayoutEffect unmount');
         });
         return text;
       }
@@ -677,7 +760,7 @@ describe('StrictEffectsMode defaults', () => {
         );
       });
 
-      assertLog([
+      expect(log).toEqual([
         'componentDidMount',
         'useLayoutEffect mount',
         'useEffect mount',
@@ -689,6 +772,7 @@ describe('StrictEffectsMode defaults', () => {
         'useEffect mount',
       ]);
 
+      log.length = 0;
       await act(() => {
         ReactNoop.render(
           <React.StrictMode>
@@ -697,18 +781,19 @@ describe('StrictEffectsMode defaults', () => {
         );
       });
 
-      assertLog([
+      expect(log).toEqual([
         'useLayoutEffect unmount',
         'useLayoutEffect mount',
         'useEffect unmount',
         'useEffect mount',
       ]);
 
+      log.length = 0;
       await act(() => {
         ReactNoop.render(null);
       });
 
-      assertLog([
+      expect(log).toEqual([
         'componentWillUnmount',
         'useLayoutEffect unmount',
         'useEffect unmount',