ReactFiberClassComponent.js

/**
 * Copyright (c) Meta Platforms, Inc. and affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *
 * @flow
 */

import type {Fiber} from './ReactInternalTypes';
import type {Lanes} from './ReactFiberLane';
import type {UpdateQueue} from './ReactFiberClassUpdateQueue';

import {
  LayoutStatic,
  Update,
  Snapshot,
  MountLayoutDev,
} from './ReactFiberFlags';
import {
  debugRenderPhaseSideEffectsForStrictMode,
  disableLegacyContext,
  enableDebugTracing,
  enableSchedulingProfiler,
  enableLazyContextPropagation,
  enableRefAsProp,
  disableDefaultPropsExceptForClasses,
} from 'shared/ReactFeatureFlags';
import ReactStrictModeWarnings from './ReactStrictModeWarnings';
import {isMounted} from './ReactFiberTreeReflection';
import {get as getInstance, set as setInstance} from 'shared/ReactInstanceMap';
import shallowEqual from 'shared/shallowEqual';
import getComponentNameFromFiber from 'react-reconciler/src/getComponentNameFromFiber';
import getComponentNameFromType from 'shared/getComponentNameFromType';
import assign from 'shared/assign';
import isArray from 'shared/isArray';
import {REACT_CONTEXT_TYPE, REACT_CONSUMER_TYPE} from 'shared/ReactSymbols';

import {
  DebugTracingMode,
  NoMode,
  StrictLegacyMode,
  StrictEffectsMode,
} from './ReactTypeOfMode';

import {
  enqueueUpdate,
  entangleTransitions,
  processUpdateQueue,
  checkHasForceUpdateAfterProcessing,
  resetHasForceUpdateBeforeProcessing,
  createUpdate,
  ReplaceState,
  ForceUpdate,
  initializeUpdateQueue,
  cloneUpdateQueue,
  suspendIfUpdateReadFromEntangledAsyncAction,
} from './ReactFiberClassUpdateQueue';
import {NoLanes} from './ReactFiberLane';
import {
  cacheContext,
  getMaskedContext,
  getUnmaskedContext,
  hasContextChanged,
  emptyContextObject,
} from './ReactFiberContext';
import {readContext, checkIfContextChanged} from './ReactFiberNewContext';
import {requestUpdateLane, scheduleUpdateOnFiber} from './ReactFiberWorkLoop';
import {logForceUpdateScheduled, logStateUpdateScheduled} from './DebugTracing';
import {
  markForceUpdateScheduled,
  markStateUpdateScheduled,
  setIsStrictModeForDevtools,
} from './ReactFiberDevToolsHook';

const fakeInternalInstance = {};

let didWarnAboutStateAssignmentForComponent;
let didWarnAboutUninitializedState;
let didWarnAboutGetSnapshotBeforeUpdateWithoutDidUpdate;
let didWarnAboutLegacyLifecyclesAndDerivedState;
let didWarnAboutUndefinedDerivedState;
let didWarnAboutDirectlyAssigningPropsToState;
let didWarnAboutContextTypeAndContextTypes;
let didWarnAboutContextTypes;
let didWarnAboutChildContextTypes;
let didWarnAboutInvalidateContextType;
let didWarnOnInvalidCallback;

if (__DEV__) {
  didWarnAboutStateAssignmentForComponent = new Set<string>();
  didWarnAboutUninitializedState = new Set<string>();
  didWarnAboutGetSnapshotBeforeUpdateWithoutDidUpdate = new Set<string>();
  didWarnAboutLegacyLifecyclesAndDerivedState = new Set<string>();
  didWarnAboutDirectlyAssigningPropsToState = new Set<string>();
  didWarnAboutUndefinedDerivedState = new Set<string>();
  didWarnAboutContextTypeAndContextTypes = new Set<string>();
  didWarnAboutContextTypes = new Set<mixed>();
  didWarnAboutChildContextTypes = new Set<mixed>();
  didWarnAboutInvalidateContextType = new Set<string>();
  didWarnOnInvalidCallback = new Set<string>();

  Object.freeze(fakeInternalInstance);
}

function warnOnInvalidCallback(callback: mixed) {
  if (__DEV__) {
    if (callback === null || typeof callback === 'function') {
      return;
    }
    // eslint-disable-next-line react-internal/safe-string-coercion
    const key = String(callback);
    if (!didWarnOnInvalidCallback.has(key)) {
      didWarnOnInvalidCallback.add(key);
      console.error(
        'Expected the last optional `callback` argument to be a ' +
          'function. Instead received: %s.',
        callback,
      );
    }
  }
}

function warnOnUndefinedDerivedState(type: any, partialState: any) {
  if (__DEV__) {
    if (partialState === undefined) {
      const componentName = getComponentNameFromType(type) || 'Component';
      if (!didWarnAboutUndefinedDerivedState.has(componentName)) {
        didWarnAboutUndefinedDerivedState.add(componentName);
        console.error(
          '%s.getDerivedStateFromProps(): A valid state object (or null) must be returned. ' +
            'You have returned undefined.',
          componentName,
        );
      }
    }
  }
}

function applyDerivedStateFromProps(
  workInProgress: Fiber,
  ctor: any,
  getDerivedStateFromProps: (props: any, state: any) => any,
  nextProps: any,
) {
  const prevState = workInProgress.memoizedState;
  let partialState = getDerivedStateFromProps(nextProps, prevState);
  if (__DEV__) {
    if (
      debugRenderPhaseSideEffectsForStrictMode &&
      workInProgress.mode & StrictLegacyMode
    ) {
      setIsStrictModeForDevtools(true);
      try {
        // Invoke the function an extra time to help detect side-effects.
        partialState = getDerivedStateFromProps(nextProps, prevState);
      } finally {
        setIsStrictModeForDevtools(false);
      }
    }
    warnOnUndefinedDerivedState(ctor, partialState);
  }
  // Merge the partial state and the previous state.
  const memoizedState =
    partialState === null || partialState === undefined
      ? prevState
      : assign({}, prevState, partialState);
  workInProgress.memoizedState = memoizedState;

  // Once the update queue is empty, persist the derived state onto the
  // base state.
  if (workInProgress.lanes === NoLanes) {
    // Queue is always non-null for classes
    const updateQueue: UpdateQueue<any> = (workInProgress.updateQueue: any);
    updateQueue.baseState = memoizedState;
  }
}

const classComponentUpdater = {
  isMounted,
  // $FlowFixMe[missing-local-annot]
  enqueueSetState(inst: any, payload: any, callback) {
    const fiber = getInstance(inst);
    const lane = requestUpdateLane(fiber);

    const update = createUpdate(lane);
    update.payload = payload;
    if (callback !== undefined && callback !== null) {
      if (__DEV__) {
        warnOnInvalidCallback(callback);
      }
      update.callback = callback;
    }

    const root = enqueueUpdate(fiber, update, lane);
    if (root !== null) {
      scheduleUpdateOnFiber(root, fiber, lane);
      entangleTransitions(root, fiber, lane);
    }

    if (__DEV__) {
      if (enableDebugTracing) {
        if (fiber.mode & DebugTracingMode) {
          const name = getComponentNameFromFiber(fiber) || 'Unknown';
          logStateUpdateScheduled(name, lane, payload);
        }
      }
    }

    if (enableSchedulingProfiler) {
      markStateUpdateScheduled(fiber, lane);
    }
  },
  enqueueReplaceState(inst: any, payload: any, callback: null) {
    const fiber = getInstance(inst);
    const lane = requestUpdateLane(fiber);

    const update = createUpdate(lane);
    update.tag = ReplaceState;
    update.payload = payload;

    if (callback !== undefined && callback !== null) {
      if (__DEV__) {
        warnOnInvalidCallback(callback);
      }
      update.callback = callback;
    }

    const root = enqueueUpdate(fiber, update, lane);
    if (root !== null) {
      scheduleUpdateOnFiber(root, fiber, lane);
      entangleTransitions(root, fiber, lane);
    }

    if (__DEV__) {
      if (enableDebugTracing) {
        if (fiber.mode & DebugTracingMode) {
          const name = getComponentNameFromFiber(fiber) || 'Unknown';
          logStateUpdateScheduled(name, lane, payload);
        }
      }
    }

    if (enableSchedulingProfiler) {
      markStateUpdateScheduled(fiber, lane);
    }
  },
  // $FlowFixMe[missing-local-annot]
  enqueueForceUpdate(inst: any, callback) {
    const fiber = getInstance(inst);
    const lane = requestUpdateLane(fiber);

    const update = createUpdate(lane);
    update.tag = ForceUpdate;

    if (callback !== undefined && callback !== null) {
      if (__DEV__) {
        warnOnInvalidCallback(callback);
      }
      update.callback = callback;
    }

    const root = enqueueUpdate(fiber, update, lane);
    if (root !== null) {
      scheduleUpdateOnFiber(root, fiber, lane);
      entangleTransitions(root, fiber, lane);
    }

    if (__DEV__) {
      if (enableDebugTracing) {
        if (fiber.mode & DebugTracingMode) {
          const name = getComponentNameFromFiber(fiber) || 'Unknown';
          logForceUpdateScheduled(name, lane);
        }
      }
    }

    if (enableSchedulingProfiler) {
      markForceUpdateScheduled(fiber, lane);
    }
  },
};

function checkShouldComponentUpdate(
  workInProgress: Fiber,
  ctor: any,
  oldProps: any,
  newProps: any,
  oldState: any,
  newState: any,
  nextContext: any,
) {
  const instance = workInProgress.stateNode;
  if (typeof instance.shouldComponentUpdate === 'function') {
    let shouldUpdate = instance.shouldComponentUpdate(
      newProps,
      newState,
      nextContext,
    );
    if (__DEV__) {
      if (
        debugRenderPhaseSideEffectsForStrictMode &&
        workInProgress.mode & StrictLegacyMode
      ) {
        setIsStrictModeForDevtools(true);
        try {
          // Invoke the function an extra time to help detect side-effects.
          shouldUpdate = instance.shouldComponentUpdate(
            newProps,
            newState,
            nextContext,
          );
        } finally {
          setIsStrictModeForDevtools(false);
        }
      }
      if (shouldUpdate === undefined) {
        console.error(
          '%s.shouldComponentUpdate(): Returned undefined instead of a ' +
            'boolean value. Make sure to return true or false.',
          getComponentNameFromType(ctor) || 'Component',
        );
      }
    }

    return shouldUpdate;
  }

  if (ctor.prototype && ctor.prototype.isPureReactComponent) {
    return (
      !shallowEqual(oldProps, newProps) || !shallowEqual(oldState, newState)
    );
  }

  return true;
}

function checkClassInstance(workInProgress: Fiber, ctor: any, newProps: any) {
  const instance = workInProgress.stateNode;
  if (__DEV__) {
    const name = getComponentNameFromType(ctor) || 'Component';
    const renderPresent = instance.render;

    if (!renderPresent) {
      if (ctor.prototype && typeof ctor.prototype.render === 'function') {
        console.error(
          'No `render` method found on the %s ' +
            'instance: did you accidentally return an object from the constructor?',
          name,
        );
      } else {
        console.error(
          'No `render` method found on the %s ' +
            'instance: you may have forgotten to define `render`.',
          name,
        );
      }
    }

    if (
      instance.getInitialState &&
      !instance.getInitialState.isReactClassApproved &&
      !instance.state
    ) {
      console.error(
        'getInitialState was defined on %s, a plain JavaScript class. ' +
          'This is only supported for classes created using React.createClass. ' +
          'Did you mean to define a state property instead?',
        name,
      );
    }
    if (
      instance.getDefaultProps &&
      !instance.getDefaultProps.isReactClassApproved
    ) {
      console.error(
        'getDefaultProps was defined on %s, a plain JavaScript class. ' +
          'This is only supported for classes created using React.createClass. ' +
          'Use a static property to define defaultProps instead.',
        name,
      );
    }
    if (instance.contextType) {
      console.error(
        'contextType was defined as an instance property on %s. Use a static ' +
          'property to define contextType instead.',
        name,
      );
    }

    if (disableLegacyContext) {
      if (ctor.childContextTypes && !didWarnAboutChildContextTypes.has(ctor)) {
        didWarnAboutChildContextTypes.add(ctor);
        console.error(
          '%s uses the legacy childContextTypes API which was removed in React 19. ' +
            'Use React.createContext() instead. (https://react.dev/link/legacy-context)',
          name,
        );
      }
      if (ctor.contextTypes && !didWarnAboutContextTypes.has(ctor)) {
        didWarnAboutContextTypes.add(ctor);
        console.error(
          '%s uses the legacy contextTypes API which was removed in React 19. ' +
            'Use React.createContext() with static contextType instead. ' +
            '(https://react.dev/link/legacy-context)',
          name,
        );
      }
    } else {
      if (instance.contextTypes) {
        console.error(
          'contextTypes was defined as an instance property on %s. Use a static ' +
            'property to define contextTypes instead.',
          name,
        );
      }

      if (
        ctor.contextType &&
        ctor.contextTypes &&
        !didWarnAboutContextTypeAndContextTypes.has(ctor)
      ) {
        didWarnAboutContextTypeAndContextTypes.add(ctor);
        console.error(
          '%s declares both contextTypes and contextType static properties. ' +
            'The legacy contextTypes property will be ignored.',
          name,
        );
      }
      if (ctor.childContextTypes && !didWarnAboutChildContextTypes.has(ctor)) {
        didWarnAboutChildContextTypes.add(ctor);
        console.error(
          '%s uses the legacy childContextTypes API which will soon be removed. ' +
            'Use React.createContext() instead. (https://react.dev/link/legacy-context)',
          name,
        );
      }
      if (ctor.contextTypes && !didWarnAboutContextTypes.has(ctor)) {
        didWarnAboutContextTypes.add(ctor);
        console.error(
          '%s uses the legacy contextTypes API which will soon be removed. ' +
            'Use React.createContext() with static contextType instead. ' +
            '(https://react.dev/link/legacy-context)',
          name,
        );
      }
    }

    if (typeof instance.componentShouldUpdate === 'function') {
      console.error(
        '%s has a method called ' +
          'componentShouldUpdate(). Did you mean shouldComponentUpdate()? ' +
          'The name is phrased as a question because the function is ' +
          'expected to return a value.',
        name,
      );
    }
    if (
      ctor.prototype &&
      ctor.prototype.isPureReactComponent &&
      typeof instance.shouldComponentUpdate !== 'undefined'
    ) {
      console.error(
        '%s has a method called shouldComponentUpdate(). ' +
          'shouldComponentUpdate should not be used when extending React.PureComponent. ' +
          'Please extend React.Component if shouldComponentUpdate is used.',
        getComponentNameFromType(ctor) || 'A pure component',
      );
    }
    if (typeof instance.componentDidUnmount === 'function') {
      console.error(
        '%s has a method called ' +
          'componentDidUnmount(). But there is no such lifecycle method. ' +
          'Did you mean componentWillUnmount()?',
        name,
      );
    }
    if (typeof instance.componentDidReceiveProps === 'function') {
      console.error(
        '%s has a method called ' +
          'componentDidReceiveProps(). But there is no such lifecycle method. ' +
          'If you meant to update the state in response to changing props, ' +
          'use componentWillReceiveProps(). If you meant to fetch data or ' +
          'run side-effects or mutations after React has updated the UI, use componentDidUpdate().',
        name,
      );
    }
    if (typeof instance.componentWillRecieveProps === 'function') {
      console.error(
        '%s has a method called ' +
          'componentWillRecieveProps(). Did you mean componentWillReceiveProps()?',
        name,
      );
    }
    if (typeof instance.UNSAFE_componentWillRecieveProps === 'function') {
      console.error(
        '%s has a method called ' +
          'UNSAFE_componentWillRecieveProps(). Did you mean UNSAFE_componentWillReceiveProps()?',
        name,
      );
    }
    const hasMutatedProps = instance.props !== newProps;
    if (instance.props !== undefined && hasMutatedProps) {
      console.error(
        'When calling super() in `%s`, make sure to pass ' +
          "up the same props that your component's constructor was passed.",
        name,
      );
    }
    if (instance.defaultProps) {
      console.error(
        'Setting defaultProps as an instance property on %s is not supported and will be ignored.' +
          ' Instead, define defaultProps as a static property on %s.',
        name,
        name,
      );
    }

    if (
      typeof instance.getSnapshotBeforeUpdate === 'function' &&
      typeof instance.componentDidUpdate !== 'function' &&
      !didWarnAboutGetSnapshotBeforeUpdateWithoutDidUpdate.has(ctor)
    ) {
      didWarnAboutGetSnapshotBeforeUpdateWithoutDidUpdate.add(ctor);
      console.error(
        '%s: getSnapshotBeforeUpdate() should be used with componentDidUpdate(). ' +
          'This component defines getSnapshotBeforeUpdate() only.',
        getComponentNameFromType(ctor),
      );
    }

    if (typeof instance.getDerivedStateFromProps === 'function') {
      console.error(
        '%s: getDerivedStateFromProps() is defined as an instance method ' +
          'and will be ignored. Instead, declare it as a static method.',
        name,
      );
    }
    if (typeof instance.getDerivedStateFromError === 'function') {
      console.error(
        '%s: getDerivedStateFromError() is defined as an instance method ' +
          'and will be ignored. Instead, declare it as a static method.',
        name,
      );
    }
    if (typeof ctor.getSnapshotBeforeUpdate === 'function') {
      console.error(
        '%s: getSnapshotBeforeUpdate() is defined as a static method ' +
          'and will be ignored. Instead, declare it as an instance method.',
        name,
      );
    }
    const state = instance.state;
    if (state && (typeof state !== 'object' || isArray(state))) {
      console.error('%s.state: must be set to an object or null', name);
    }
    if (
      typeof instance.getChildContext === 'function' &&
      typeof ctor.childContextTypes !== 'object'
    ) {
      console.error(
        '%s.getChildContext(): childContextTypes must be defined in order to ' +
          'use getChildContext().',
        name,
      );
    }
  }
}

function constructClassInstance(
  workInProgress: Fiber,
  ctor: any,
  props: any,
): any {
  let isLegacyContextConsumer = false;
  let unmaskedContext = emptyContextObject;
  let context = emptyContextObject;
  const contextType = ctor.contextType;

  if (__DEV__) {
    if ('contextType' in ctor) {
      const isValid =
        // Allow null for conditional declaration
        contextType === null ||
        (contextType !== undefined &&
          contextType.$$typeof === REACT_CONTEXT_TYPE);

      if (!isValid && !didWarnAboutInvalidateContextType.has(ctor)) {
        didWarnAboutInvalidateContextType.add(ctor);

        let addendum = '';
        if (contextType === undefined) {
          addendum =
            ' However, it is set to undefined. ' +
            'This can be caused by a typo or by mixing up named and default imports. ' +
            'This can also happen due to a circular dependency, so ' +
            'try moving the createContext() call to a separate file.';
        } else if (typeof contextType !== 'object') {
          addendum = ' However, it is set to a ' + typeof contextType + '.';
        } else if (contextType.$$typeof === REACT_CONSUMER_TYPE) {
          addendum = ' Did you accidentally pass the Context.Consumer instead?';
        } else {
          addendum =
            ' However, it is set to an object with keys {' +
            Object.keys(contextType).join(', ') +
            '}.';
        }
        console.error(
          '%s defines an invalid contextType. ' +
            'contextType should point to the Context object returned by React.createContext().%s',
          getComponentNameFromType(ctor) || 'Component',
          addendum,
        );
      }
    }
  }

  if (typeof contextType === 'object' && contextType !== null) {
    context = readContext((contextType: any));
  } else if (!disableLegacyContext) {
    unmaskedContext = getUnmaskedContext(workInProgress, ctor, true);
    const contextTypes = ctor.contextTypes;
    isLegacyContextConsumer =
      contextTypes !== null && contextTypes !== undefined;
    context = isLegacyContextConsumer
      ? getMaskedContext(workInProgress, unmaskedContext)
      : emptyContextObject;
  }

  let instance = new ctor(props, context);
  // Instantiate twice to help detect side-effects.
  if (__DEV__) {
    if (
      debugRenderPhaseSideEffectsForStrictMode &&
      workInProgress.mode & StrictLegacyMode
    ) {
      setIsStrictModeForDevtools(true);
      try {
        instance = new ctor(props, context);
      } finally {
        setIsStrictModeForDevtools(false);
      }
    }
  }

  const state = (workInProgress.memoizedState =
    instance.state !== null && instance.state !== undefined
      ? instance.state
      : null);
  instance.updater = classComponentUpdater;
  workInProgress.stateNode = instance;
  // The instance needs access to the fiber so that it can schedule updates
  setInstance(instance, workInProgress);
  if (__DEV__) {
    instance._reactInternalInstance = fakeInternalInstance;
  }

  if (__DEV__) {
    if (typeof ctor.getDerivedStateFromProps === 'function' && state === null) {
      const componentName = getComponentNameFromType(ctor) || 'Component';
      if (!didWarnAboutUninitializedState.has(componentName)) {
        didWarnAboutUninitializedState.add(componentName);
        console.error(
          '`%s` uses `getDerivedStateFromProps` but its initial state is ' +
            '%s. This is not recommended. Instead, define the initial state by ' +
            'assigning an object to `this.state` in the constructor of `%s`. ' +
            'This ensures that `getDerivedStateFromProps` arguments have a consistent shape.',
          componentName,
          instance.state === null ? 'null' : 'undefined',
          componentName,
        );
      }
    }

    // If new component APIs are defined, "unsafe" lifecycles won't be called.
    // Warn about these lifecycles if they are present.
    // Don't warn about react-lifecycles-compat polyfilled methods though.
    if (
      typeof ctor.getDerivedStateFromProps === 'function' ||
      typeof instance.getSnapshotBeforeUpdate === 'function'
    ) {
      let foundWillMountName = null;
      let foundWillReceivePropsName = null;
      let foundWillUpdateName = null;
      if (
        typeof instance.componentWillMount === 'function' &&
        instance.componentWillMount.__suppressDeprecationWarning !== true
      ) {
        foundWillMountName = 'componentWillMount';
      } else if (typeof instance.UNSAFE_componentWillMount === 'function') {
        foundWillMountName = 'UNSAFE_componentWillMount';
      }
      if (
        typeof instance.componentWillReceiveProps === 'function' &&
        instance.componentWillReceiveProps.__suppressDeprecationWarning !== true
      ) {
        foundWillReceivePropsName = 'componentWillReceiveProps';
      } else if (
        typeof instance.UNSAFE_componentWillReceiveProps === 'function'
      ) {
        foundWillReceivePropsName = 'UNSAFE_componentWillReceiveProps';
      }
      if (
        typeof instance.componentWillUpdate === 'function' &&
        instance.componentWillUpdate.__suppressDeprecationWarning !== true
      ) {
        foundWillUpdateName = 'componentWillUpdate';
      } else if (typeof instance.UNSAFE_componentWillUpdate === 'function') {
        foundWillUpdateName = 'UNSAFE_componentWillUpdate';
      }
      if (
        foundWillMountName !== null ||
        foundWillReceivePropsName !== null ||
        foundWillUpdateName !== null
      ) {
        const componentName = getComponentNameFromType(ctor) || 'Component';
        const newApiName =
          typeof ctor.getDerivedStateFromProps === 'function'
            ? 'getDerivedStateFromProps()'
            : 'getSnapshotBeforeUpdate()';
        if (!didWarnAboutLegacyLifecyclesAndDerivedState.has(componentName)) {
          didWarnAboutLegacyLifecyclesAndDerivedState.add(componentName);
          console.error(
            'Unsafe legacy lifecycles will not be called for components using new component APIs.\n\n' +
              '%s uses %s but also contains the following legacy lifecycles:%s%s%s\n\n' +
              'The above lifecycles should be removed. Learn more about this warning here:\n' +
              'https://react.dev/link/unsafe-component-lifecycles',
            componentName,
            newApiName,
            foundWillMountName !== null ? `\n  ${foundWillMountName}` : '',
            foundWillReceivePropsName !== null
              ? `\n  ${foundWillReceivePropsName}`
              : '',
            foundWillUpdateName !== null ? `\n  ${foundWillUpdateName}` : '',
          );
        }
      }
    }
  }

  // Cache unmasked context so we can avoid recreating masked context unless necessary.
  // ReactFiberContext usually updates this cache but can't for newly-created instances.
  if (isLegacyContextConsumer) {
    cacheContext(workInProgress, unmaskedContext, context);
  }

  return instance;
}

function callComponentWillMount(workInProgress: Fiber, instance: any) {
  const oldState = instance.state;

  if (typeof instance.componentWillMount === 'function') {
    instance.componentWillMount();
  }
  if (typeof instance.UNSAFE_componentWillMount === 'function') {
    instance.UNSAFE_componentWillMount();
  }

  if (oldState !== instance.state) {
    if (__DEV__) {
      console.error(
        '%s.componentWillMount(): Assigning directly to this.state is ' +
          "deprecated (except inside a component's " +
          'constructor). Use setState instead.',
        getComponentNameFromFiber(workInProgress) || 'Component',
      );
    }
    classComponentUpdater.enqueueReplaceState(instance, instance.state, null);
  }
}

function callComponentWillReceiveProps(
  workInProgress: Fiber,
  instance: any,
  newProps: any,
  nextContext: any,
) {
  const oldState = instance.state;
  if (typeof instance.componentWillReceiveProps === 'function') {
    instance.componentWillReceiveProps(newProps, nextContext);
  }
  if (typeof instance.UNSAFE_componentWillReceiveProps === 'function') {
    instance.UNSAFE_componentWillReceiveProps(newProps, nextContext);
  }

  if (instance.state !== oldState) {
    if (__DEV__) {
      const componentName =
        getComponentNameFromFiber(workInProgress) || 'Component';
      if (!didWarnAboutStateAssignmentForComponent.has(componentName)) {
        didWarnAboutStateAssignmentForComponent.add(componentName);
        console.error(
          '%s.componentWillReceiveProps(): Assigning directly to ' +
            "this.state is deprecated (except inside a component's " +
            'constructor). Use setState instead.',
          componentName,
        );
      }
    }
    classComponentUpdater.enqueueReplaceState(instance, instance.state, null);
  }
}

// Invokes the mount life-cycles on a previously never rendered instance.
function mountClassInstance(
  workInProgress: Fiber,
  ctor: any,
  newProps: any,
  renderLanes: Lanes,
): void {
  if (__DEV__) {
    checkClassInstance(workInProgress, ctor, newProps);
  }

  const instance = workInProgress.stateNode;
  instance.props = newProps;
  instance.state = workInProgress.memoizedState;
  instance.refs = {};

  initializeUpdateQueue(workInProgress);

  const contextType = ctor.contextType;
  if (typeof contextType === 'object' && contextType !== null) {
    instance.context = readContext(contextType);
  } else if (disableLegacyContext) {
    instance.context = emptyContextObject;
  } else {
    const unmaskedContext = getUnmaskedContext(workInProgress, ctor, true);
    instance.context = getMaskedContext(workInProgress, unmaskedContext);
  }

  if (__DEV__) {
    if (instance.state === newProps) {
      const componentName = getComponentNameFromType(ctor) || 'Component';
      if (!didWarnAboutDirectlyAssigningPropsToState.has(componentName)) {
        didWarnAboutDirectlyAssigningPropsToState.add(componentName);
        console.error(
          '%s: It is not recommended to assign props directly to state ' +
            "because updates to props won't be reflected in state. " +
            'In most cases, it is better to use props directly.',
          componentName,
        );
      }
    }

    if (workInProgress.mode & StrictLegacyMode) {
      ReactStrictModeWarnings.recordLegacyContextWarning(
        workInProgress,
        instance,
      );
    }

    ReactStrictModeWarnings.recordUnsafeLifecycleWarnings(
      workInProgress,
      instance,
    );
  }

  instance.state = workInProgress.memoizedState;

  const getDerivedStateFromProps = ctor.getDerivedStateFromProps;
  if (typeof getDerivedStateFromProps === 'function') {
    applyDerivedStateFromProps(
      workInProgress,
      ctor,
      getDerivedStateFromProps,
      newProps,
    );
    instance.state = workInProgress.memoizedState;
  }

  // In order to support react-lifecycles-compat polyfilled components,
  // Unsafe lifecycles should not be invoked for components using the new APIs.
  if (
    typeof ctor.getDerivedStateFromProps !== 'function' &&
    typeof instance.getSnapshotBeforeUpdate !== 'function' &&
    (typeof instance.UNSAFE_componentWillMount === 'function' ||
      typeof instance.componentWillMount === 'function')
  ) {
    callComponentWillMount(workInProgress, instance);
    // If we had additional state updates during this life-cycle, let's
    // process them now.
    processUpdateQueue(workInProgress, newProps, instance, renderLanes);
    suspendIfUpdateReadFromEntangledAsyncAction();
    instance.state = workInProgress.memoizedState;
  }

  if (typeof instance.componentDidMount === 'function') {
    workInProgress.flags |= Update | LayoutStatic;
  }
  if (__DEV__ && (workInProgress.mode & StrictEffectsMode) !== NoMode) {
    workInProgress.flags |= MountLayoutDev;
  }
}

function resumeMountClassInstance(
  workInProgress: Fiber,
  ctor: any,
  newProps: any,
  renderLanes: Lanes,
): boolean {
  const instance = workInProgress.stateNode;

  const unresolvedOldProps = workInProgress.memoizedProps;
  const oldProps = resolveClassComponentProps(
    ctor,
    unresolvedOldProps,
    workInProgress.type === workInProgress.elementType,
  );
  instance.props = oldProps;

  const oldContext = instance.context;
  const contextType = ctor.contextType;
  let nextContext = emptyContextObject;
  if (typeof contextType === 'object' && contextType !== null) {
    nextContext = readContext(contextType);
  } else if (!disableLegacyContext) {
    const nextLegacyUnmaskedContext = getUnmaskedContext(
      workInProgress,
      ctor,
      true,
    );
    nextContext = getMaskedContext(workInProgress, nextLegacyUnmaskedContext);
  }

  const getDerivedStateFromProps = ctor.getDerivedStateFromProps;
  const hasNewLifecycles =
    typeof getDerivedStateFromProps === 'function' ||
    typeof instance.getSnapshotBeforeUpdate === 'function';

  // When comparing whether props changed, we should compare using the
  // unresolved props object that is stored on the fiber, rather than the
  // one that gets assigned to the instance, because that object may have been
  // cloned to resolve default props and/or remove `ref`.
  const unresolvedNewProps = workInProgress.pendingProps;
  const didReceiveNewProps = unresolvedNewProps !== unresolvedOldProps;

  // Note: During these life-cycles, instance.props/instance.state are what
  // ever the previously attempted to render - not the "current". However,
  // during componentDidUpdate we pass the "current" props.

  // In order to support react-lifecycles-compat polyfilled components,
  // Unsafe lifecycles should not be invoked for components using the new APIs.
  if (
    !hasNewLifecycles &&
    (typeof instance.UNSAFE_componentWillReceiveProps === 'function' ||
      typeof instance.componentWillReceiveProps === 'function')
  ) {
    if (didReceiveNewProps || oldContext !== nextContext) {
      callComponentWillReceiveProps(
        workInProgress,
        instance,
        newProps,
        nextContext,
      );
    }
  }

  resetHasForceUpdateBeforeProcessing();

  const oldState = workInProgress.memoizedState;
  let newState = (instance.state = oldState);
  processUpdateQueue(workInProgress, newProps, instance, renderLanes);
  suspendIfUpdateReadFromEntangledAsyncAction();
  newState = workInProgress.memoizedState;
  if (
    !didReceiveNewProps &&
    oldState === newState &&
    !hasContextChanged() &&
    !checkHasForceUpdateAfterProcessing()
  ) {
    // If an update was already in progress, we should schedule an Update
    // effect even though we're bailing out, so that cWU/cDU are called.
    if (typeof instance.componentDidMount === 'function') {
      workInProgress.flags |= Update | LayoutStatic;
    }
    if (__DEV__ && (workInProgress.mode & StrictEffectsMode) !== NoMode) {
      workInProgress.flags |= MountLayoutDev;
    }
    return false;
  }

  if (typeof getDerivedStateFromProps === 'function') {
    applyDerivedStateFromProps(
      workInProgress,
      ctor,
      getDerivedStateFromProps,
      newProps,
    );
    newState = workInProgress.memoizedState;
  }

  const shouldUpdate =
    checkHasForceUpdateAfterProcessing() ||
    checkShouldComponentUpdate(
      workInProgress,
      ctor,
      oldProps,
      newProps,
      oldState,
      newState,
      nextContext,
    );

  if (shouldUpdate) {
    // In order to support react-lifecycles-compat polyfilled components,
    // Unsafe lifecycles should not be invoked for components using the new APIs.
    if (
      !hasNewLifecycles &&
      (typeof instance.UNSAFE_componentWillMount === 'function' ||
        typeof instance.componentWillMount === 'function')
    ) {
      if (typeof instance.componentWillMount === 'function') {
        instance.componentWillMount();
      }
      if (typeof instance.UNSAFE_componentWillMount === 'function') {
        instance.UNSAFE_componentWillMount();
      }
    }
    if (typeof instance.componentDidMount === 'function') {
      workInProgress.flags |= Update | LayoutStatic;
    }
    if (__DEV__ && (workInProgress.mode & StrictEffectsMode) !== NoMode) {
      workInProgress.flags |= MountLayoutDev;
    }
  } else {
    // If an update was already in progress, we should schedule an Update
    // effect even though we're bailing out, so that cWU/cDU are called.
    if (typeof instance.componentDidMount === 'function') {
      workInProgress.flags |= Update | LayoutStatic;
    }
    if (__DEV__ && (workInProgress.mode & StrictEffectsMode) !== NoMode) {
      workInProgress.flags |= MountLayoutDev;
    }

    // If shouldComponentUpdate returned false, we should still update the
    // memoized state to indicate that this work can be reused.
    workInProgress.memoizedProps = newProps;
    workInProgress.memoizedState = newState;
  }

  // Update the existing instance's state, props, and context pointers even
  // if shouldComponentUpdate returns false.
  instance.props = newProps;
  instance.state = newState;
  instance.context = nextContext;

  return shouldUpdate;
}

// Invokes the update life-cycles and returns false if it shouldn't rerender.
function updateClassInstance(
  current: Fiber,
  workInProgress: Fiber,
  ctor: any,
  newProps: any,
  renderLanes: Lanes,
): boolean {
  const instance = workInProgress.stateNode;

  cloneUpdateQueue(current, workInProgress);

  const unresolvedOldProps = workInProgress.memoizedProps;
  const oldProps = resolveClassComponentProps(
    ctor,
    unresolvedOldProps,
    workInProgress.type === workInProgress.elementType,
  );
  instance.props = oldProps;
  const unresolvedNewProps = workInProgress.pendingProps;

  const oldContext = instance.context;
  const contextType = ctor.contextType;
  let nextContext = emptyContextObject;
  if (typeof contextType === 'object' && contextType !== null) {
    nextContext = readContext(contextType);
  } else if (!disableLegacyContext) {
    const nextUnmaskedContext = getUnmaskedContext(workInProgress, ctor, true);
    nextContext = getMaskedContext(workInProgress, nextUnmaskedContext);
  }

  const getDerivedStateFromProps = ctor.getDerivedStateFromProps;
  const hasNewLifecycles =
    typeof getDerivedStateFromProps === 'function' ||
    typeof instance.getSnapshotBeforeUpdate === 'function';

  // Note: During these life-cycles, instance.props/instance.state are what
  // ever the previously attempted to render - not the "current". However,
  // during componentDidUpdate we pass the "current" props.

  // In order to support react-lifecycles-compat polyfilled components,
  // Unsafe lifecycles should not be invoked for components using the new APIs.
  if (
    !hasNewLifecycles &&
    (typeof instance.UNSAFE_componentWillReceiveProps === 'function' ||
      typeof instance.componentWillReceiveProps === 'function')
  ) {
    if (
      unresolvedOldProps !== unresolvedNewProps ||
      oldContext !== nextContext
    ) {
      callComponentWillReceiveProps(
        workInProgress,
        instance,
        newProps,
        nextContext,
      );
    }
  }

  resetHasForceUpdateBeforeProcessing();

  const oldState = workInProgress.memoizedState;
  let newState = (instance.state = oldState);
  processUpdateQueue(workInProgress, newProps, instance, renderLanes);
  suspendIfUpdateReadFromEntangledAsyncAction();
  newState = workInProgress.memoizedState;

  if (
    unresolvedOldProps === unresolvedNewProps &&
    oldState === newState &&
    !hasContextChanged() &&
    !checkHasForceUpdateAfterProcessing() &&
    !(
      enableLazyContextPropagation &&
      current !== null &&
      current.dependencies !== null &&
      checkIfContextChanged(current.dependencies)
    )
  ) {
    // If an update was already in progress, we should schedule an Update
    // effect even though we're bailing out, so that cWU/cDU are called.
    if (typeof instance.componentDidUpdate === 'function') {
      if (
        unresolvedOldProps !== current.memoizedProps ||
        oldState !== current.memoizedState
      ) {
        workInProgress.flags |= Update;
      }
    }
    if (typeof instance.getSnapshotBeforeUpdate === 'function') {
      if (
        unresolvedOldProps !== current.memoizedProps ||
        oldState !== current.memoizedState
      ) {
        workInProgress.flags |= Snapshot;
      }
    }
    return false;
  }

  if (typeof getDerivedStateFromProps === 'function') {
    applyDerivedStateFromProps(
      workInProgress,
      ctor,
      getDerivedStateFromProps,
      newProps,
    );
    newState = workInProgress.memoizedState;
  }

  const shouldUpdate =
    checkHasForceUpdateAfterProcessing() ||
    checkShouldComponentUpdate(
      workInProgress,
      ctor,
      oldProps,
      newProps,
      oldState,
      newState,
      nextContext,
    ) ||
    // TODO: In some cases, we'll end up checking if context has changed twice,
    // both before and after `shouldComponentUpdate` has been called. Not ideal,
    // but I'm loath to refactor this function. This only happens for memoized
    // components so it's not that common.
    (enableLazyContextPropagation &&
      current !== null &&
      current.dependencies !== null &&
      checkIfContextChanged(current.dependencies));

  if (shouldUpdate) {
    // In order to support react-lifecycles-compat polyfilled components,
    // Unsafe lifecycles should not be invoked for components using the new APIs.
    if (
      !hasNewLifecycles &&
      (typeof instance.UNSAFE_componentWillUpdate === 'function' ||
        typeof instance.componentWillUpdate === 'function')
    ) {
      if (typeof instance.componentWillUpdate === 'function') {
        instance.componentWillUpdate(newProps, newState, nextContext);
      }
      if (typeof instance.UNSAFE_componentWillUpdate === 'function') {
        instance.UNSAFE_componentWillUpdate(newProps, newState, nextContext);
      }
    }
    if (typeof instance.componentDidUpdate === 'function') {
      workInProgress.flags |= Update;
    }
    if (typeof instance.getSnapshotBeforeUpdate === 'function') {
      workInProgress.flags |= Snapshot;
    }
  } else {
    // If an update was already in progress, we should schedule an Update
    // effect even though we're bailing out, so that cWU/cDU are called.
    if (typeof instance.componentDidUpdate === 'function') {
      if (
        unresolvedOldProps !== current.memoizedProps ||
        oldState !== current.memoizedState
      ) {
        workInProgress.flags |= Update;
      }
    }
    if (typeof instance.getSnapshotBeforeUpdate === 'function') {
      if (
        unresolvedOldProps !== current.memoizedProps ||
        oldState !== current.memoizedState
      ) {
        workInProgress.flags |= Snapshot;
      }
    }

    // If shouldComponentUpdate returned false, we should still update the
    // memoized props/state to indicate that this work can be reused.
    workInProgress.memoizedProps = newProps;
    workInProgress.memoizedState = newState;
  }

  // Update the existing instance's state, props, and context pointers even
  // if shouldComponentUpdate returns false.
  instance.props = newProps;
  instance.state = newState;
  instance.context = nextContext;

  return shouldUpdate;
}

export function resolveClassComponentProps(
  Component: any,
  baseProps: Object,
  // Only resolve default props if this is a lazy component. Otherwise, they
  // would have already been resolved by the JSX runtime.
  // TODO: We're going to remove default prop resolution from the JSX runtime
  // and keep it only for class components. As part of that change, we should
  // remove this extra check.
  alreadyResolvedDefaultProps: boolean,
): Object {
  let newProps = baseProps;

  if (enableRefAsProp) {
    // Remove ref from the props object, if it exists.
    if ('ref' in baseProps) {
      newProps = ({}: any);
      for (const propName in baseProps) {
        if (propName !== 'ref') {
          newProps[propName] = baseProps[propName];
        }
      }
    }
  }

  // Resolve default props.
  const defaultProps = Component.defaultProps;
  if (
    defaultProps &&
    // If disableDefaultPropsExceptForClasses is true, we always resolve
    // default props here in the reconciler, rather than in the JSX runtime.
    (disableDefaultPropsExceptForClasses || !alreadyResolvedDefaultProps)
  ) {
    // We may have already copied the props object above to remove ref. If so,
    // we can modify that. Otherwise, copy the props object with Object.assign.
    if (newProps === baseProps) {
      newProps = assign({}, newProps);
    }
    // Taken from old JSX runtime, where this used to live.
    for (const propName in defaultProps) {
      if (newProps[propName] === undefined) {
        newProps[propName] = defaultProps[propName];
      }
    }
  }

  return newProps;
}

export {
  constructClassInstance,
  mountClassInstance,
  resumeMountClassInstance,
  updateClassInstance,
};