Warn when a callback ref returns a function (#23145)

Author: gaearon

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

@@ -352,7 +352,6 @@ describe('ref swapping', () => {
     );
   });
 
-  // @gate !__DEV__ || warnAboutCallbackRefReturningFunction
   it('should warn about callback refs returning a function', () => {
     const container = document.createElement('div');
     expect(() => {

packages/react-reconciler/src/ReactFiberCommitWork.new.js

@@ -39,7 +39,6 @@ import {
   deletedTreeCleanUpLevel,
   enableSuspenseLayoutEffectSemantics,
   enableUpdaterTracking,
-  warnAboutCallbackRefReturningFunction,
   enableCache,
 } from 'shared/ReactFeatureFlags';
 import {
@@ -286,10 +285,7 @@ function safelyDetachRef(current: Fiber, nearestMountedAncestor: Fiber | null) {
         captureCommitPhaseError(current, nearestMountedAncestor, error);
       }
       if (__DEV__) {
-        if (
-          warnAboutCallbackRefReturningFunction &&
-          typeof retVal === 'function'
-        ) {
+        if (typeof retVal === 'function') {
           console.error(
             'Unexpected return value from a callback ref in %s. ' +
               'A callback ref should not return a function.',
@@ -1151,10 +1147,7 @@ function commitAttachRef(finishedWork: Fiber) {
         retVal = ref(instanceToUse);
       }
       if (__DEV__) {
-        if (
-          warnAboutCallbackRefReturningFunction &&
-          typeof retVal === 'function'
-        ) {
+        if (typeof retVal === 'function') {
           console.error(
             'Unexpected return value from a callback ref in %s. ' +
               'A callback ref should not return a function.',

packages/react-reconciler/src/ReactFiberCommitWork.old.js

@@ -39,7 +39,6 @@ import {
   deletedTreeCleanUpLevel,
   enableSuspenseLayoutEffectSemantics,
   enableUpdaterTracking,
-  warnAboutCallbackRefReturningFunction,
   enableCache,
 } from 'shared/ReactFeatureFlags';
 import {
@@ -286,10 +285,7 @@ function safelyDetachRef(current: Fiber, nearestMountedAncestor: Fiber | null) {
         captureCommitPhaseError(current, nearestMountedAncestor, error);
       }
       if (__DEV__) {
-        if (
-          warnAboutCallbackRefReturningFunction &&
-          typeof retVal === 'function'
-        ) {
+        if (typeof retVal === 'function') {
           console.error(
             'Unexpected return value from a callback ref in %s. ' +
               'A callback ref should not return a function.',
@@ -1151,10 +1147,7 @@ function commitAttachRef(finishedWork: Fiber) {
         retVal = ref(instanceToUse);
       }
       if (__DEV__) {
-        if (
-          warnAboutCallbackRefReturningFunction &&
-          typeof retVal === 'function'
-        ) {
+        if (typeof retVal === 'function') {
           console.error(
             'Unexpected return value from a callback ref in %s. ' +
               'A callback ref should not return a function.',

packages/shared/ReactFeatureFlags.js

@@ -178,8 +178,6 @@ export const deferRenderPhaseUpdateToNextBatch = false;
 
 export const enableUseRefAccessWarning = false;
 
-export const warnAboutCallbackRefReturningFunction = false;
-
 export const disableSchedulerTimeoutInWorkLoop = false;
 
 export const enableLazyContextPropagation = false;

packages/shared/forks/ReactFeatureFlags.native-fb.js

@@ -66,7 +66,6 @@ export const deferRenderPhaseUpdateToNextBatch = false;
 export const enableStrictEffects = __DEV__;
 export const createRootStrictEffectsByDefault = false;
 export const enableUseRefAccessWarning = false;
-export const warnAboutCallbackRefReturningFunction = false;
 
 export const disableSchedulerTimeoutInWorkLoop = false;
 export const enableLazyContextPropagation = false;

packages/shared/forks/ReactFeatureFlags.native-oss.js

@@ -57,7 +57,6 @@ export const deferRenderPhaseUpdateToNextBatch = false;
 export const enableStrictEffects = false;
 export const createRootStrictEffectsByDefault = false;
 export const enableUseRefAccessWarning = false;
-export const warnAboutCallbackRefReturningFunction = false;
 
 export const disableSchedulerTimeoutInWorkLoop = false;
 export const enableLazyContextPropagation = false;

packages/shared/forks/ReactFeatureFlags.test-renderer.js

@@ -57,7 +57,6 @@ export const deferRenderPhaseUpdateToNextBatch = false;
 export const enableStrictEffects = false;
 export const createRootStrictEffectsByDefault = false;
 export const enableUseRefAccessWarning = false;
-export const warnAboutCallbackRefReturningFunction = false;
 
 export const disableSchedulerTimeoutInWorkLoop = false;
 export const enableLazyContextPropagation = false;

packages/shared/forks/ReactFeatureFlags.test-renderer.native.js

@@ -56,7 +56,6 @@ export const enableClientRenderFallbackOnHydrationMismatch = true;
 export const enableStrictEffects = false;
 export const createRootStrictEffectsByDefault = false;
 export const enableUseRefAccessWarning = false;
-export const warnAboutCallbackRefReturningFunction = false;
 
 export const disableSchedulerTimeoutInWorkLoop = false;
 export const enableLazyContextPropagation = false;

packages/shared/forks/ReactFeatureFlags.test-renderer.www.js

@@ -57,7 +57,6 @@ export const deferRenderPhaseUpdateToNextBatch = false;
 export const enableStrictEffects = true;
 export const createRootStrictEffectsByDefault = false;
 export const enableUseRefAccessWarning = false;
-export const warnAboutCallbackRefReturningFunction = false;
 
 export const disableSchedulerTimeoutInWorkLoop = false;
 export const enableLazyContextPropagation = false;

packages/shared/forks/ReactFeatureFlags.testing.js

@@ -57,7 +57,6 @@ export const deferRenderPhaseUpdateToNextBatch = false;
 export const enableStrictEffects = false;
 export const createRootStrictEffectsByDefault = false;
 export const enableUseRefAccessWarning = false;
-export const warnAboutCallbackRefReturningFunction = false;
 
 export const disableSchedulerTimeoutInWorkLoop = false;
 export const enableLazyContextPropagation = false;

packages/shared/forks/ReactFeatureFlags.testing.www.js

@@ -57,7 +57,6 @@ export const deferRenderPhaseUpdateToNextBatch = false;
 export const enableStrictEffects = false;
 export const createRootStrictEffectsByDefault = false;
 export const enableUseRefAccessWarning = false;
-export const warnAboutCallbackRefReturningFunction = false;
 
 export const disableSchedulerTimeoutInWorkLoop = false;
 export const enableLazyContextPropagation = false;

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

@@ -19,7 +19,6 @@ export const enableFilterEmptyStringAttributesDOM = __VARIANT__;
 export const enableLegacyFBSupport = __VARIANT__;
 export const skipUnmountedBoundaries = __VARIANT__;
 export const enableUseRefAccessWarning = __VARIANT__;
-export const warnAboutCallbackRefReturningFunction = __VARIANT__;
 export const deletedTreeCleanUpLevel = __VARIANT__ ? 3 : 1;
 export const enableProfilerNestedUpdateScheduledHook = __VARIANT__;
 export const disableSchedulerTimeoutInWorkLoop = __VARIANT__;

packages/shared/forks/ReactFeatureFlags.www.js

@@ -67,7 +67,6 @@ export const warnAboutDefaultPropsOnFunctionComponents = false;
 export const enableGetInspectorDataForInstanceInProduction = false;
 export const enableSuspenseServerRenderer = true;
 export const enableSelectiveHydration = true;
-export const warnAboutCallbackRefReturningFunction = true;
 
 export const enableLazyElements = true;
 export const enableCache = true;