Update Flow to 0.257 (#34253)

kassens · web-flow · commit ec5dd0ab3acb · 2025-08-21T13:30:01.000-04:00
After an easy couple version with #34252, this version is less flexible (and safer) on inferring exported types mainly. We require to annotate some exported types to differentiate between `boolean` and literal `true` types, etc.
diff --git a/package.json b/package.json
@@ -73,8 +73,8 @@
     "eslint-plugin-react-internal": "link:./scripts/eslint-rules",
     "fbjs-scripts": "^3.0.1",
     "filesize": "^6.0.1",
-    "flow-bin": "^0.256",
-    "flow-remove-types": "^2.256",
+    "flow-bin": "^0.257",
+    "flow-remove-types": "^2.257",
     "glob": "^7.1.6",
     "glob-stream": "^6.1.0",
     "google-closure-compiler": "^20230206.0.0",
diff --git a/packages/react-devtools-shared/src/backend/NativeStyleEditor/setupNativeStyleEditor.js b/packages/react-devtools-shared/src/backend/NativeStyleEditor/setupNativeStyleEditor.js
@@ -194,7 +194,7 @@ function renameStyle(
   const {instance, style} = data;
 
   const newStyle = newName
-    ? {[oldName]: undefined, [newName]: value}
+    ? {[oldName]: (undefined: string | void), [newName]: value}
     : {[oldName]: undefined};
 
   let customStyle;
diff --git a/packages/react-devtools-shared/src/config/DevToolsFeatureFlags.core-fb.js b/packages/react-devtools-shared/src/config/DevToolsFeatureFlags.core-fb.js
@@ -13,9 +13,9 @@
  * It should always be imported from "react-devtools-feature-flags".
  ************************************************************************/
 
-export const enableLogger = true;
-export const enableStyleXFeatures = true;
-export const isInternalFacebookBuild = true;
+export const enableLogger: boolean = true;
+export const enableStyleXFeatures: boolean = true;
+export const isInternalFacebookBuild: boolean = true;
 
 /************************************************************************
  * Do not edit the code below.
diff --git a/packages/react-devtools-shared/src/config/DevToolsFeatureFlags.core-oss.js b/packages/react-devtools-shared/src/config/DevToolsFeatureFlags.core-oss.js
@@ -13,9 +13,9 @@
  * It should always be imported from "react-devtools-feature-flags".
  ************************************************************************/
 
-export const enableLogger = false;
-export const enableStyleXFeatures = false;
-export const isInternalFacebookBuild = false;
+export const enableLogger: boolean = false;
+export const enableStyleXFeatures: boolean = false;
+export const isInternalFacebookBuild: boolean = false;
 
 /************************************************************************
  * Do not edit the code below.
diff --git a/packages/react-devtools-shared/src/config/DevToolsFeatureFlags.default.js b/packages/react-devtools-shared/src/config/DevToolsFeatureFlags.default.js
@@ -13,6 +13,6 @@
  * It should always be imported from "react-devtools-feature-flags".
  ************************************************************************/
 
-export const enableLogger = false;
-export const enableStyleXFeatures = false;
-export const isInternalFacebookBuild = false;
+export const enableLogger: boolean = false;
+export const enableStyleXFeatures: boolean = false;
+export const isInternalFacebookBuild: boolean = false;
diff --git a/packages/react-devtools-shared/src/config/DevToolsFeatureFlags.extension-fb.js b/packages/react-devtools-shared/src/config/DevToolsFeatureFlags.extension-fb.js
@@ -13,9 +13,9 @@
  * It should always be imported from "react-devtools-feature-flags".
  ************************************************************************/
 
-export const enableLogger = true;
-export const enableStyleXFeatures = true;
-export const isInternalFacebookBuild = true;
+export const enableLogger: boolean = true;
+export const enableStyleXFeatures: boolean = true;
+export const isInternalFacebookBuild: boolean = true;
 
 /************************************************************************
  * Do not edit the code below.
diff --git a/packages/react-devtools-shared/src/config/DevToolsFeatureFlags.extension-oss.js b/packages/react-devtools-shared/src/config/DevToolsFeatureFlags.extension-oss.js
@@ -13,9 +13,9 @@
  * It should always be imported from "react-devtools-feature-flags".
  ************************************************************************/
 
-export const enableLogger = false;
-export const enableStyleXFeatures = false;
-export const isInternalFacebookBuild = false;
+export const enableLogger: boolean = false;
+export const enableStyleXFeatures: boolean = false;
+export const isInternalFacebookBuild: boolean = false;
 
 /************************************************************************
  * Do not edit the code below.
diff --git a/packages/react-devtools-timeline/src/content-views/constants.js b/packages/react-devtools-timeline/src/content-views/constants.js
@@ -16,7 +16,7 @@ export const MARKER_TEXT_PADDING = 8;
 export const COLOR_HOVER_DIM_DELTA = 5;
 export const TOP_ROW_PADDING = 4;
 export const NATIVE_EVENT_HEIGHT = 14;
-export const SUSPENSE_EVENT_HEIGHT = 14;
+export const SUSPENSE_EVENT_HEIGHT: number = 14;
 export const PENDING_SUSPENSE_EVENT_SIZE = 8;
 export const REACT_EVENT_DIAMETER = 6;
 export const USER_TIMING_MARK_SIZE = 8;
diff --git a/packages/react-dom-bindings/src/client/ReactFiberConfigDOM.js b/packages/react-dom-bindings/src/client/ReactFiberConfigDOM.js
@@ -746,7 +746,7 @@ export const scheduleTimeout: any =
   typeof setTimeout === 'function' ? setTimeout : (undefined: any);
 export const cancelTimeout: any =
   typeof clearTimeout === 'function' ? clearTimeout : (undefined: any);
-export const noTimeout = -1;
+export const noTimeout: -1 = -1;
 const localPromise = typeof Promise === 'function' ? Promise : undefined;
 const localRequestAnimationFrame =
   typeof requestAnimationFrame === 'function'
diff --git a/packages/react-dom-bindings/src/events/DOMPluginEventSystem.js b/packages/react-dom-bindings/src/events/DOMPluginEventSystem.js
@@ -407,7 +407,7 @@ export function listenToNativeEventForNonManagedEventTarget(
   isCapturePhaseListener: boolean,
   target: EventTarget,
 ): void {
-  let eventSystemFlags = IS_EVENT_HANDLE_NON_MANAGED_NODE;
+  let eventSystemFlags: number = IS_EVENT_HANDLE_NON_MANAGED_NODE;
   const listenerSet = getEventListenerSet(target);
   const listenerSetKey = getListenerSetKey(
     domEventName,
diff --git a/packages/react-native-renderer/src/ReactFiberConfigFabric.js b/packages/react-native-renderer/src/ReactFiberConfigFabric.js
@@ -431,7 +431,7 @@ export const warnsIfNotActing = false;
 
 export const scheduleTimeout = setTimeout;
 export const cancelTimeout = clearTimeout;
-export const noTimeout = -1;
+export const noTimeout: -1 = -1;
 
 // -------------------
 //     Persistence
diff --git a/packages/react-native-renderer/src/ReactFiberConfigNative.js b/packages/react-native-renderer/src/ReactFiberConfigNative.js
@@ -326,7 +326,7 @@ export const warnsIfNotActing = true;
 
 export const scheduleTimeout = setTimeout;
 export const cancelTimeout = clearTimeout;
-export const noTimeout = -1;
+export const noTimeout: -1 = -1;
 
 export function shouldSetTextContent(type: string, props: Props): boolean {
   // TODO (bvaughn) Revisit this decision.
diff --git a/packages/react-reconciler/src/ReactFiber.js b/packages/react-reconciler/src/ReactFiber.js
@@ -522,7 +522,7 @@ export function createHostRootFiber(
   tag: RootTag,
   isStrictMode: boolean,
 ): Fiber {
-  let mode;
+  let mode: number;
   if (disableLegacyMode || tag === ConcurrentRoot) {
     mode = ConcurrentMode;
     if (isStrictMode === true) {
@@ -551,7 +551,7 @@ export function createFiberFromTypeAndProps(
   mode: TypeOfMode,
   lanes: Lanes,
 ): Fiber {
-  let fiberTag = FunctionComponent;
+  let fiberTag: WorkTag = FunctionComponent;
   // The resolved type is set if we know what the final type will be. I.e. it's not lazy.
   let resolvedType = type;
   if (typeof type === 'function') {
diff --git a/packages/react-reconciler/src/ReactFiberCommitWork.js b/packages/react-reconciler/src/ReactFiberCommitWork.js
@@ -283,6 +283,7 @@ import {
   untrackNamedViewTransition,
 } from './ReactFiberDuplicateViewTransitions';
 import {markIndicatorHandled} from './ReactFiberRootScheduler';
+import type {Flags} from './ReactFiberFlags';
 
 // Used during the commit phase to track the state of the Offscreen component stack.
 // Allows us to avoid traversing the return path to find the nearest Offscreen ancestor.
@@ -4490,7 +4491,7 @@ export function commitPassiveUnmountEffects(finishedWork: Fiber): void {
 // Note that MaySuspendCommit and ShouldSuspendCommit also includes named
 // ViewTransitions so that we know to also visit those to collect appearing
 // pairs.
-let suspenseyCommitFlag = ShouldSuspendCommit;
+let suspenseyCommitFlag: Flags = ShouldSuspendCommit;
 export function accumulateSuspenseyCommit(
   finishedWork: Fiber,
   committedLanes: Lanes,
diff --git a/packages/react-reconciler/src/ReactFiberCompleteWork.js b/packages/react-reconciler/src/ReactFiberCompleteWork.js
@@ -190,6 +190,7 @@ import {
   popRootMarkerInstance,
 } from './ReactFiberTracingMarkerComponent';
 import {suspendCommit} from './ReactFiberThenable';
+import type {Flags} from './ReactFiberFlags';
 
 /**
  * Tag the fiber with an update effect. This turns a Placement into
@@ -780,7 +781,7 @@ function bubbleProperties(completedWork: Fiber) {
     completedWork.alternate.child === completedWork.child;
 
   let newChildLanes: Lanes = NoLanes;
-  let subtreeFlags = NoFlags;
+  let subtreeFlags: Flags = NoFlags;
 
   if (!didBailout) {
     // Bubble up the earliest expiration time.
diff --git a/packages/react-test-renderer/src/ReactFiberConfigTestHost.js b/packages/react-test-renderer/src/ReactFiberConfigTestHost.js
@@ -268,7 +268,7 @@ export const warnsIfNotActing = true;
 export const scheduleTimeout = setTimeout;
 export const cancelTimeout = clearTimeout;
 
-export const noTimeout = -1;
+export const noTimeout: -1 = -1;
 
 // -------------------
 //     Mutation
diff --git a/packages/react-test-renderer/src/ReactTestRenderer.js b/packages/react-test-renderer/src/ReactTestRenderer.js
@@ -61,6 +61,7 @@ import {
 } from 'shared/ReactFeatureFlags';
 
 import noop from 'shared/noop';
+import type {WorkTag} from 'react-reconciler/src/ReactWorkTags';
 
 const defaultOnDefaultTransitionIndicator: () => void | (() => void) = noop;
 
@@ -244,7 +245,7 @@ function toTree(node: null | Fiber): $FlowFixMe {
   }
 }
 
-const validWrapperTypes = new Set([
+const validWrapperTypes: Set<WorkTag> = new Set([
   FunctionComponent,
   ClassComponent,
   HostComponent,
diff --git a/packages/react/index.development.js b/packages/react/index.development.js
@@ -19,7 +19,6 @@ export type Portal = React$Portal;
 export type ElementProps<C> = React$ElementProps<C>;
 export type ElementConfig<C> = React$ElementConfig<C>;
 export type ElementRef<C> = React$ElementRef<C>;
-export type Config<Props, DefaultProps> = React$Config<Props, DefaultProps>;
 export type ChildrenArray<+T> = $ReadOnlyArray<ChildrenArray<T>> | T;
 
 // Export all exports so that they're available in tests.
diff --git a/packages/react/index.js b/packages/react/index.js
@@ -21,7 +21,6 @@ export type RefSetter<-I> = React$RefSetter<I>;
 export type ElementProps<C> = React$ElementProps<C>;
 export type ElementConfig<C> = React$ElementConfig<C>;
 export type ElementRef<C> = React$ElementRef<C>;
-export type Config<Props, DefaultProps> = React$Config<Props, DefaultProps>;
 export type ChildrenArray<+T> = $ReadOnlyArray<ChildrenArray<T>> | T;
 
 export {
diff --git a/packages/scheduler/src/forks/Scheduler.js b/packages/scheduler/src/forks/Scheduler.js
@@ -83,7 +83,7 @@ var timerQueue: Array<Task> = [];
 var taskIdCounter = 1;
 
 var currentTask = null;
-var currentPriorityLevel = NormalPriority;
+var currentPriorityLevel: PriorityLevel = NormalPriority;
 
 // This is set while performing work, to prevent re-entrance.
 var isPerformingWork = false;
@@ -441,7 +441,7 @@ let taskTimeoutID: TimeoutID = (-1: any);
 // thread, like user events. By default, it yields multiple times per frame.
 // It does not attempt to align with frame boundaries, since most tasks don't
 // need to be frame aligned; for those that do, use requestAnimationFrame.
-let frameInterval = frameYieldMs;
+let frameInterval: number = frameYieldMs;
 let startTime = -1;
 
 function shouldYieldToHost(): boolean {
diff --git a/packages/scheduler/src/forks/SchedulerMock.js b/packages/scheduler/src/forks/SchedulerMock.js
@@ -70,7 +70,7 @@ var timerQueue: Array<Task> = [];
 var taskIdCounter = 1;
 
 var currentTask = null;
-var currentPriorityLevel = NormalPriority;
+var currentPriorityLevel: PriorityLevel = NormalPriority;
 
 // This is set while performing work, to prevent re-entrance.
 var isPerformingWork = false;
diff --git a/packages/scheduler/src/forks/SchedulerNative.js b/packages/scheduler/src/forks/SchedulerNative.js
@@ -10,17 +10,18 @@
 import * as Scheduler from './Scheduler';
 import type {Callback, Task} from './Scheduler';
 import type {PriorityLevel} from '../SchedulerPriorities';
+import typeof * as PriorityLevels from '../SchedulerPriorities';
 import typeof * as SchedulerExportsType from './Scheduler';
 import typeof * as SchedulerNativeExportsType from './SchedulerNative';
 
 // This type is supposed to reflect the actual methods and arguments currently supported by the C++ implementation:
 // https://github.com/facebook/react-native/blob/main/packages/react-native/ReactCommon/react/renderer/runtimescheduler/RuntimeSchedulerBinding.cpp
 type NativeSchedulerType = {
-  unstable_ImmediatePriority: PriorityLevel,
-  unstable_UserBlockingPriority: PriorityLevel,
-  unstable_NormalPriority: PriorityLevel,
-  unstable_IdlePriority: PriorityLevel,
-  unstable_LowPriority: PriorityLevel,
+  unstable_ImmediatePriority: PriorityLevels['ImmediatePriority'],
+  unstable_UserBlockingPriority: PriorityLevels['UserBlockingPriority'],
+  unstable_NormalPriority: PriorityLevels['NormalPriority'],
+  unstable_IdlePriority: PriorityLevels['IdlePriority'],
+  unstable_LowPriority: PriorityLevels['LowPriority'],
   unstable_scheduleCallback: (
     priorityLevel: PriorityLevel,
     callback: Callback,
@@ -34,27 +35,27 @@ type NativeSchedulerType = {
 
 declare const nativeRuntimeScheduler: void | NativeSchedulerType;
 
-export const unstable_UserBlockingPriority: PriorityLevel =
+export const unstable_UserBlockingPriority: PriorityLevels['UserBlockingPriority'] =
   typeof nativeRuntimeScheduler !== 'undefined'
     ? nativeRuntimeScheduler.unstable_UserBlockingPriority
     : Scheduler.unstable_UserBlockingPriority;
 
-export const unstable_NormalPriority: PriorityLevel =
+export const unstable_NormalPriority: PriorityLevels['NormalPriority'] =
   typeof nativeRuntimeScheduler !== 'undefined'
     ? nativeRuntimeScheduler.unstable_NormalPriority
     : Scheduler.unstable_NormalPriority;
 
-export const unstable_IdlePriority: PriorityLevel =
+export const unstable_IdlePriority: PriorityLevels['IdlePriority'] =
   typeof nativeRuntimeScheduler !== 'undefined'
     ? nativeRuntimeScheduler.unstable_IdlePriority
     : Scheduler.unstable_IdlePriority;
 
-export const unstable_LowPriority: PriorityLevel =
+export const unstable_LowPriority: PriorityLevels['LowPriority'] =
   typeof nativeRuntimeScheduler !== 'undefined'
     ? nativeRuntimeScheduler.unstable_LowPriority
     : Scheduler.unstable_LowPriority;
 
-export const unstable_ImmediatePriority: PriorityLevel =
+export const unstable_ImmediatePriority: PriorityLevels['ImmediatePriority'] =
   typeof nativeRuntimeScheduler !== 'undefined'
     ? nativeRuntimeScheduler.unstable_ImmediatePriority
     : Scheduler.unstable_ImmediatePriority;
diff --git a/packages/scheduler/src/forks/SchedulerPostTask.js b/packages/scheduler/src/forks/SchedulerPostTask.js
@@ -55,7 +55,7 @@ export const unstable_now = getCurrentTime;
 const yieldInterval = 5;
 let deadline = 0;
 
-let currentPriorityLevel_DEPRECATED = NormalPriority;
+let currentPriorityLevel_DEPRECATED: PriorityLevel = NormalPriority;
 
 // Always yield at the end of the frame.
 export function unstable_shouldYield(): boolean {
diff --git a/packages/shared/ReactFeatureFlags.js b/packages/shared/ReactFeatureFlags.js
diff --git a/packages/shared/forks/ReactFeatureFlags.native-fb.js b/packages/shared/forks/ReactFeatureFlags.native-fb.js
diff --git a/packages/shared/forks/ReactFeatureFlags.native-oss.js b/packages/shared/forks/ReactFeatureFlags.native-oss.js
diff --git a/packages/shared/forks/ReactFeatureFlags.test-renderer.js b/packages/shared/forks/ReactFeatureFlags.test-renderer.js
diff --git a/packages/shared/forks/ReactFeatureFlags.test-renderer.www.js b/packages/shared/forks/ReactFeatureFlags.test-renderer.www.js
diff --git a/packages/shared/forks/ReactFeatureFlags.www-dynamic.js b/packages/shared/forks/ReactFeatureFlags.www-dynamic.js
diff --git a/packages/shared/forks/ReactFeatureFlags.www.js b/packages/shared/forks/ReactFeatureFlags.www.js
diff --git a/yarn.lock b/yarn.lock
