Debug tracing tests for CPU bound suspense (#19943)

Author: Brian Vaughn

packages/react-reconciler/src/__tests__/DebugTracing-test.internal.js

@@ -96,6 +96,45 @@ describe('DebugTracing', () => {
     expect(logs).toEqual(['log: ⚛️ Example resolved']);
   });
 
+  // @gate experimental && build === 'development' && enableDebugTracing
+  it('should log sync render with CPU suspense', () => {
+    function Example() {
+      console.log('<Example/>');
+      return null;
+    }
+
+    function Wrapper({children}) {
+      console.log('<Wrapper/>');
+      return children;
+    }
+
+    ReactTestRenderer.create(
+      <React.unstable_DebugTracingMode>
+        <Wrapper>
+          <React.Suspense fallback={null} unstable_expectedLoadTime={1}>
+            <Example />
+          </React.Suspense>
+        </Wrapper>
+      </React.unstable_DebugTracingMode>,
+    );
+
+    expect(logs).toEqual([
+      'group: ⚛️ render (0b0000000000000000000000000000001)',
+      'log: <Wrapper/>',
+      'groupEnd: ⚛️ render (0b0000000000000000000000000000001)',
+    ]);
+
+    logs.splice(0);
+
+    expect(Scheduler).toFlushUntilNextPaint([]);
+
+    expect(logs).toEqual([
+      'group: ⚛️ render (0b0000010000000000000000000000000)',
+      'log: <Example/>',
+      'groupEnd: ⚛️ render (0b0000010000000000000000000000000)',
+    ]);
+  });
+
   // @gate experimental && build === 'development' && enableDebugTracing
   it('should log concurrent render with suspense', async () => {
     const fakeSuspensePromise = Promise.resolve(true);
@@ -130,6 +169,52 @@ describe('DebugTracing', () => {
     expect(logs).toEqual(['log: ⚛️ Example resolved']);
   });
 
+  // @gate experimental && build === 'development' && enableDebugTracing
+  it('should log concurrent render with CPU suspense', () => {
+    function Example() {
+      console.log('<Example/>');
+      return null;
+    }
+
+    function Wrapper({children}) {
+      console.log('<Wrapper/>');
+      return children;
+    }
+
+    ReactTestRenderer.create(
+      <React.unstable_DebugTracingMode>
+        <Wrapper>
+          <React.Suspense fallback={null} unstable_expectedLoadTime={1}>
+            <Example />
+          </React.Suspense>
+        </Wrapper>
+      </React.unstable_DebugTracingMode>,
+      {unstable_isConcurrent: true},
+    );
+
+    expect(logs).toEqual([]);
+
+    logs.splice(0);
+
+    expect(Scheduler).toFlushUntilNextPaint([]);
+
+    expect(logs).toEqual([
+      'group: ⚛️ render (0b0000000000000000000001000000000)',
+      'log: <Wrapper/>',
+      'groupEnd: ⚛️ render (0b0000000000000000000001000000000)',
+    ]);
+
+    logs.splice(0);
+
+    expect(Scheduler).toFlushUntilNextPaint([]);
+
+    expect(logs).toEqual([
+      'group: ⚛️ render (0b0000010000000000000000000000000)',
+      'log: <Example/>',
+      'groupEnd: ⚛️ render (0b0000010000000000000000000000000)',
+    ]);
+  });
+
   // @gate experimental && build === 'development' && enableDebugTracing
   it('should log cascading class component updates', () => {
     class Example extends React.Component {
@@ -191,12 +276,23 @@ describe('DebugTracing', () => {
       expect(Scheduler).toFlushUntilNextPaint([]);
     }).toErrorDev('Cannot update during an existing state transition');
 
-    expect(logs).toEqual([
-      'group: ⚛️ render (0b0000000000000000000001000000000)',
-      'log: ⚛️ Example updated state (0b0000000000000000000010000000000)',
-      'log: ⚛️ Example updated state (0b0000000000000000000010000000000)',
-      'groupEnd: ⚛️ render (0b0000000000000000000001000000000)',
-    ]);
+    gate(flags => {
+      if (flags.new) {
+        expect(logs).toEqual([
+          'group: ⚛️ render (0b0000000000000000000001000000000)',
+          'log: ⚛️ Example updated state (0b0000000000000000000001000000000)',
+          'log: ⚛️ Example updated state (0b0000000000000000000001000000000)',
+          'groupEnd: ⚛️ render (0b0000000000000000000001000000000)',
+        ]);
+      } else {
+        expect(logs).toEqual([
+          'group: ⚛️ render (0b0000000000000000000001000000000)',
+          'log: ⚛️ Example updated state (0b0000000000000000000010000000000)',
+          'log: ⚛️ Example updated state (0b0000000000000000000010000000000)',
+          'groupEnd: ⚛️ render (0b0000000000000000000001000000000)',
+        ]);
+      }
+    });
   });
 
   // @gate experimental && build === 'development' && enableDebugTracing
@@ -274,12 +370,24 @@ describe('DebugTracing', () => {
         {unstable_isConcurrent: true},
       );
     });
-    expect(logs).toEqual([
-      'group: ⚛️ render (0b0000000000000000000001000000000)',
-      'log: ⚛️ Example updated state (0b0000000000000000000010000000000)',
-      'log: ⚛️ Example updated state (0b0000000000000000000010000000000)', // debugRenderPhaseSideEffectsForStrictMode
-      'groupEnd: ⚛️ render (0b0000000000000000000001000000000)',
-    ]);
+
+    gate(flags => {
+      if (flags.new) {
+        expect(logs).toEqual([
+          'group: ⚛️ render (0b0000000000000000000001000000000)',
+          'log: ⚛️ Example updated state (0b0000000000000000000001000000000)',
+          'log: ⚛️ Example updated state (0b0000000000000000000001000000000)', // debugRenderPhaseSideEffectsForStrictMode
+          'groupEnd: ⚛️ render (0b0000000000000000000001000000000)',
+        ]);
+      } else {
+        expect(logs).toEqual([
+          'group: ⚛️ render (0b0000000000000000000001000000000)',
+          'log: ⚛️ Example updated state (0b0000000000000000000010000000000)',
+          'log: ⚛️ Example updated state (0b0000000000000000000010000000000)', // debugRenderPhaseSideEffectsForStrictMode
+          'groupEnd: ⚛️ render (0b0000000000000000000001000000000)',
+        ]);
+      }
+    });
   });
 
   // @gate experimental && build === 'development' && enableDebugTracing

packages/shared/forks/ReactFeatureFlags.www-dynamic.js

@@ -25,7 +25,7 @@ export const enableEagerRootListeners = !__VARIANT__;
 // It logs information to the console about React scheduling, rendering, and commit phases.
 //
 // NOTE: This feature will only work in DEV mode; all callsights are wrapped with __DEV__.
-export const enableDebugTracing = false;
+export const enableDebugTracing = __EXPERIMENTAL__;
 
 // This only has an effect in the new reconciler. But also, the new reconciler
 // is only enabled when __VARIANT__ is true. So this is set to the opposite of