Cleanup enableSyncDefaultUpdate flag (#26236)

This feature flag is enabled everywhere.

packages/react-art/src/__tests__/ReactART-test.js

@@ -33,8 +33,6 @@ const ReactTestRenderer = require('react-test-renderer');
 
 // Isolate the noop renderer
 jest.resetModules();
-const ReactNoop = require('react-noop-renderer');
-const Scheduler = require('scheduler');
 
 let Group;
 let Shape;
@@ -359,58 +357,6 @@ describe('ReactART', () => {
     doClick(instance);
     expect(onClick2).toBeCalled();
   });
-
-  // @gate !enableSyncDefaultUpdates
-  it('can concurrently render with a "primary" renderer while sharing context', () => {
-    const CurrentRendererContext = React.createContext(null);
-
-    function Yield(props) {
-      Scheduler.unstable_yieldValue(props.value);
-      return null;
-    }
-
-    let ops = [];
-    function LogCurrentRenderer() {
-      return (
-        <CurrentRendererContext.Consumer>
-          {currentRenderer => {
-            ops.push(currentRenderer);
-            return null;
-          }}
-        </CurrentRendererContext.Consumer>
-      );
-    }
-
-    // Using test renderer instead of the DOM renderer here because async
-    // testing APIs for the DOM renderer don't exist.
-    ReactNoop.render(
-      <CurrentRendererContext.Provider value="Test">
-        <Yield value="A" />
-        <Yield value="B" />
-        <LogCurrentRenderer />
-        <Yield value="C" />
-      </CurrentRendererContext.Provider>,
-    );
-
-    expect(Scheduler).toFlushAndYieldThrough(['A']);
-
-    ReactDOM.render(
-      <Surface>
-        <LogCurrentRenderer />
-        <CurrentRendererContext.Provider value="ART">
-          <LogCurrentRenderer />
-        </CurrentRendererContext.Provider>
-      </Surface>,
-      container,
-    );
-
-    expect(ops).toEqual([null, 'ART']);
-
-    ops = [];
-    expect(Scheduler).toFlushAndYield(['B', 'C']);
-
-    expect(ops).toEqual(['Test']);
-  });
 });
 
 describe('ReactARTComponents', () => {

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

@@ -305,11 +305,7 @@ describe('ReactDOMNativeEventHeuristic-test', () => {
       expect(container.textContent).toEqual('not hovered');
 
       expect(Scheduler).toFlushAndYieldThrough(['hovered']);
-      if (gate(flags => flags.enableSyncDefaultUpdates)) {
-        expect(container.textContent).toEqual('hovered');
-      } else {
-        expect(container.textContent).toEqual('not hovered');
-      }
+      expect(container.textContent).toEqual('hovered');
     });
     expect(container.textContent).toEqual('hovered');
   });

packages/react-dom/src/__tests__/ReactDOMServerPartialHydration-test.internal.js

@@ -2044,14 +2044,7 @@ describe('ReactDOMServerPartialHydration', () => {
     suspend = true;
 
     await act(async () => {
-      if (gate(flags => flags.enableSyncDefaultUpdates)) {
-        expect(Scheduler).toFlushAndYieldThrough(['Before', 'After']);
-      } else {
-        expect(Scheduler).toFlushAndYieldThrough(['Before']);
-        // This took a long time to render.
-        Scheduler.unstable_advanceTime(1000);
-        expect(Scheduler).toFlushAndYield(['After']);
-      }
+      expect(Scheduler).toFlushAndYieldThrough(['Before', 'After']);
 
       // This will cause us to skip the second row completely.
     });

packages/react-dom/src/events/__tests__/DOMPluginEventSystem-test.internal.js

@@ -1965,13 +1965,9 @@ describe('DOMPluginEventSystem', () => {
             log.length = 0;
 
             // Increase counter
-            if (gate(flags => flags.enableSyncDefaultUpdates)) {
-              React.startTransition(() => {
-                root.render(<Test counter={1} />);
-              });
-            } else {
+            React.startTransition(() => {
               root.render(<Test counter={1} />);
-            }
+            });
             // Yield before committing
             expect(Scheduler).toFlushAndYieldThrough(['Test']);
 

packages/react-reconciler/src/ReactFiber.js

@@ -33,7 +33,6 @@ import {
   enableProfilerTimer,
   enableScopeAPI,
   enableLegacyHidden,
-  enableSyncDefaultUpdates,
   allowConcurrentByDefault,
   enableTransitionTracing,
   enableDebugTracing,
@@ -459,11 +458,9 @@ export function createHostRootFiber(
       mode |= StrictLegacyMode | StrictEffectsMode;
     }
     if (
-      // We only use this flag for our repo tests to check both behaviors.
-      // TODO: Flip this flag and rename it something like "forceConcurrentByDefaultForTesting"
-      !enableSyncDefaultUpdates ||
       // Only for internal experiments.
-      (allowConcurrentByDefault && concurrentUpdatesByDefaultOverride)
+      allowConcurrentByDefault &&
+      concurrentUpdatesByDefaultOverride
     ) {
       mode |= ConcurrentUpdatesByDefaultMode;
     }

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

@@ -63,13 +63,9 @@ describe('ReactSuspenseList', () => {
     root.render(<App show={false} />);
     expect(Scheduler).toFlushAndYield([]);
 
-    if (gate(flags => flags.enableSyncDefaultUpdates)) {
-      React.startTransition(() => {
-        root.render(<App show={true} />);
-      });
-    } else {
+    React.startTransition(() => {
       root.render(<App show={true} />);
-    }
+    });
     expect(Scheduler).toFlushAndYield([
       'Suspend! [A]',
       'Suspend! [B]',

packages/react-reconciler/src/__tests__/ReactExpiration-test.js

@@ -115,13 +115,9 @@ describe('ReactExpiration', () => {
   }
 
   it('increases priority of updates as time progresses', () => {
-    if (gate(flags => flags.enableSyncDefaultUpdates)) {
-      React.startTransition(() => {
-        ReactNoop.render(<span prop="done" />);
-      });
-    } else {
+    React.startTransition(() => {
       ReactNoop.render(<span prop="done" />);
-    }
+    });
 
     expect(ReactNoop).toMatchRenderedOutput(null);
 
@@ -162,13 +158,9 @@ describe('ReactExpiration', () => {
 
     // First, show what happens for updates in two separate events.
     // Schedule an update.
-    if (gate(flags => flags.enableSyncDefaultUpdates)) {
-      React.startTransition(() => {
-        ReactNoop.render(<TextClass text="A" />);
-      });
-    } else {
+    React.startTransition(() => {
       ReactNoop.render(<TextClass text="A" />);
-    }
+    });
     // Advance the timer.
     Scheduler.unstable_advanceTime(2000);
     // Partially flush the first update, then interrupt it.
@@ -223,13 +215,9 @@ describe('ReactExpiration', () => {
 
       // First, show what happens for updates in two separate events.
       // Schedule an update.
-      if (gate(flags => flags.enableSyncDefaultUpdates)) {
-        React.startTransition(() => {
-          ReactNoop.render(<TextClass text="A" />);
-        });
-      } else {
+      React.startTransition(() => {
         ReactNoop.render(<TextClass text="A" />);
-      }
+      });
       // Advance the timer.
       Scheduler.unstable_advanceTime(2000);
       // Partially flush the first update, then interrupt it.
@@ -301,13 +289,9 @@ describe('ReactExpiration', () => {
     }
 
     // Initial mount
-    if (gate(flags => flags.enableSyncDefaultUpdates)) {
-      React.startTransition(() => {
-        ReactNoop.render(<App />);
-      });
-    } else {
+    React.startTransition(() => {
       ReactNoop.render(<App />);
-    }
+    });
     expect(Scheduler).toFlushAndYield([
       'initial [A] [render]',
       'initial [B] [render]',
@@ -320,13 +304,9 @@ describe('ReactExpiration', () => {
     ]);
 
     // Partial update
-    if (gate(flags => flags.enableSyncDefaultUpdates)) {
-      React.startTransition(() => {
-        subscribers.forEach(s => s.setState({text: '1'}));
-      });
-    } else {
+    React.startTransition(() => {
       subscribers.forEach(s => s.setState({text: '1'}));
-    }
+    });
     expect(Scheduler).toFlushAndYieldThrough([
       '1 [A] [render]',
       '1 [B] [render]',
@@ -358,13 +338,9 @@ describe('ReactExpiration', () => {
       );
     }
 
-    if (gate(flags => flags.enableSyncDefaultUpdates)) {
-      React.startTransition(() => {
-        root.render(<App />);
-      });
-    } else {
+    React.startTransition(() => {
       root.render(<App />);
-    }
+    });
 
     expect(Scheduler).toFlushAndYieldThrough(['A']);
     expect(Scheduler).toFlushAndYieldThrough(['B']);
@@ -392,13 +368,9 @@ describe('ReactExpiration', () => {
         </>
       );
     }
-    if (gate(flags => flags.enableSyncDefaultUpdates)) {
-      React.startTransition(() => {
-        root.render(<App />);
-      });
-    } else {
+    React.startTransition(() => {
       root.render(<App />);
-    }
+    });
 
     expect(Scheduler).toFlushAndYieldThrough(['A']);
     expect(Scheduler).toFlushAndYieldThrough(['B']);
@@ -426,13 +398,9 @@ describe('ReactExpiration', () => {
     // current time.
     ReactNoop = require('react-noop-renderer');
 
-    if (gate(flags => flags.enableSyncDefaultUpdates)) {
-      React.startTransition(() => {
-        ReactNoop.render('Hi');
-      });
-    } else {
+    React.startTransition(() => {
       ReactNoop.render('Hi');
-    }
+    });
 
     // The update should not have expired yet.
     flushNextRenderIfExpired();
@@ -455,13 +423,9 @@ describe('ReactExpiration', () => {
     // Before scheduling an update, advance the current time.
     Scheduler.unstable_advanceTime(10000);
 
-    if (gate(flags => flags.enableSyncDefaultUpdates)) {
-      React.startTransition(() => {
-        ReactNoop.render('Hi');
-      });
-    } else {
+    React.startTransition(() => {
       ReactNoop.render('Hi');
-    }
+    });
     flushNextRenderIfExpired();
     expect(Scheduler).toHaveYielded([]);
     expect(ReactNoop).toMatchRenderedOutput(null);
@@ -504,13 +468,9 @@ describe('ReactExpiration', () => {
 
     // First demonstrate what happens when there's no starvation
     await act(async () => {
-      if (gate(flags => flags.enableSyncDefaultUpdates)) {
-        React.startTransition(() => {
-          updateNormalPri();
-        });
-      } else {
+      React.startTransition(() => {
         updateNormalPri();
-      }
+      });
       expect(Scheduler).toFlushAndYieldThrough(['Sync pri: 0']);
       updateSyncPri();
       expect(Scheduler).toHaveYielded(['Sync pri: 1', 'Normal pri: 0']);
@@ -528,13 +488,9 @@ describe('ReactExpiration', () => {
 
     // Do the same thing, but starve the first update
     await act(async () => {
-      if (gate(flags => flags.enableSyncDefaultUpdates)) {
-        React.startTransition(() => {
-          updateNormalPri();
-        });
-      } else {
+      React.startTransition(() => {
         updateNormalPri();
-      }
+      });
       expect(Scheduler).toFlushAndYieldThrough(['Sync pri: 1']);
 
       // This time, a lot of time has elapsed since the normal pri update
@@ -690,13 +646,9 @@ describe('ReactExpiration', () => {
     expect(root).toMatchRenderedOutput('A0BC');
 
     await act(async () => {
-      if (gate(flags => flags.enableSyncDefaultUpdates)) {
-        React.startTransition(() => {
-          root.render(<App step={1} />);
-        });
-      } else {
+      React.startTransition(() => {
         root.render(<App step={1} />);
-      }
+      });
       expect(Scheduler).toFlushAndYield([
         'Suspend! [A1]',
         'B',

packages/react-reconciler/src/__tests__/ReactFlushSync-test.js

@@ -41,13 +41,9 @@ describe('ReactFlushSync', () => {
 
     const root = ReactNoop.createRoot();
     await act(async () => {
-      if (gate(flags => flags.enableSyncDefaultUpdates)) {
-        React.startTransition(() => {
-          root.render(<App />);
-        });
-      } else {
+      React.startTransition(() => {
         root.render(<App />);
-      }
+      });
       // This will yield right before the passive effect fires
       expect(Scheduler).toFlushUntilNextPaint(['0, 0']);