import difference from 'lodash/difference'; import union from 'lodash/union'; import isPlainObject from 'lodash/isPlainObject'; import $$observable from './symbol-observable'; import { Action, Observable, PreloadedState, Reducer, Store, StoreEnhancer, StoreEnhancerStoreCreator, } from 'redux'; export const ActionTypes = { PERFORM_ACTION: 'PERFORM_ACTION', RESET: 'RESET', ROLLBACK: 'ROLLBACK', COMMIT: 'COMMIT', SWEEP: 'SWEEP', TOGGLE_ACTION: 'TOGGLE_ACTION', SET_ACTIONS_ACTIVE: 'SET_ACTIONS_ACTIVE', JUMP_TO_STATE: 'JUMP_TO_STATE', JUMP_TO_ACTION: 'JUMP_TO_ACTION', REORDER_ACTION: 'REORDER_ACTION', IMPORT_STATE: 'IMPORT_STATE', LOCK_CHANGES: 'LOCK_CHANGES', PAUSE_RECORDING: 'PAUSE_RECORDING', } as const; const isChrome = typeof window === 'object' && (typeof (window as typeof window & { chrome: unknown }).chrome !== 'undefined' || (typeof window.process !== 'undefined' && (window.process as typeof window.process & { type: unknown }).type === 'renderer')); const isChromeOrNode = isChrome || (typeof process !== 'undefined' && process.release && process.release.name === 'node'); export interface PerformAction> { type: typeof ActionTypes.PERFORM_ACTION; action: A; timestamp: number; stack: string | undefined; } interface ResetAction { type: typeof ActionTypes.RESET; timestamp: number; } interface RollbackAction { type: typeof ActionTypes.ROLLBACK; timestamp: number; } interface CommitAction { type: typeof ActionTypes.COMMIT; timestamp: number; } interface SweepAction { type: typeof ActionTypes.SWEEP; } interface ToggleAction { type: typeof ActionTypes.TOGGLE_ACTION; id: number; } interface SetActionsActiveAction { type: typeof ActionTypes.SET_ACTIONS_ACTIVE; start: number; end: number; active: boolean; } interface ReorderAction { type: typeof ActionTypes.REORDER_ACTION; actionId: number; beforeActionId: number; } interface JumpToStateAction { type: typeof ActionTypes.JUMP_TO_STATE; index: number; } interface JumpToActionAction { type: typeof ActionTypes.JUMP_TO_ACTION; actionId: number; } interface ImportStateAction, MonitorState> { type: typeof ActionTypes.IMPORT_STATE; nextLiftedState: LiftedState | readonly A[]; preloadedState?: S; noRecompute?: boolean | undefined; } interface LockChangesAction { type: typeof ActionTypes.LOCK_CHANGES; status: boolean; } interface PauseRecordingAction { type: typeof ActionTypes.PAUSE_RECORDING; status: boolean; } export type LiftedAction, MonitorState> = | PerformAction | ResetAction | RollbackAction | CommitAction | SweepAction | ToggleAction | SetActionsActiveAction | ReorderAction | JumpToStateAction | JumpToActionAction | ImportStateAction | LockChangesAction | PauseRecordingAction; /** * Action creators to change the History state. */ export const ActionCreators = { performAction>( action: A, trace?: ((action: A) => string | undefined) | boolean, traceLimit?: number, // eslint-disable-next-line @typescript-eslint/ban-types toExcludeFromTrace?: Function ) { if (!isPlainObject(action)) { throw new Error( 'Actions must be plain objects. ' + 'Use custom middleware for async actions.' ); } if (typeof action.type === 'undefined') { throw new Error( 'Actions may not have an undefined "type" property. ' + 'Have you misspelled a constant?' ); } let stack; if (trace) { let extraFrames = 0; if (typeof trace === 'function') { stack = trace(action); } else { const error = Error(); let prevStackTraceLimit; if (Error.captureStackTrace && isChromeOrNode) { // avoid error-polyfill if (traceLimit && Error.stackTraceLimit < traceLimit) { prevStackTraceLimit = Error.stackTraceLimit; Error.stackTraceLimit = traceLimit; } Error.captureStackTrace(error, toExcludeFromTrace); } else { extraFrames = 3; } stack = error.stack; if (prevStackTraceLimit) Error.stackTraceLimit = prevStackTraceLimit; if ( extraFrames || typeof Error.stackTraceLimit !== 'number' || (traceLimit && Error.stackTraceLimit > traceLimit) ) { if (stack != null) { const frames = stack.split('\n'); if (traceLimit && frames.length > traceLimit) { stack = frames .slice( 0, traceLimit + extraFrames + (frames[0].startsWith('Error') ? 1 : 0) ) .join('\n'); } } } } } return { type: ActionTypes.PERFORM_ACTION, action, timestamp: Date.now(), stack, }; }, reset(): ResetAction { return { type: ActionTypes.RESET, timestamp: Date.now() }; }, rollback(): RollbackAction { return { type: ActionTypes.ROLLBACK, timestamp: Date.now() }; }, commit(): CommitAction { return { type: ActionTypes.COMMIT, timestamp: Date.now() }; }, sweep(): SweepAction { return { type: ActionTypes.SWEEP }; }, toggleAction(id: number): ToggleAction { return { type: ActionTypes.TOGGLE_ACTION, id }; }, setActionsActive( start: number, end: number, active = true ): SetActionsActiveAction { return { type: ActionTypes.SET_ACTIONS_ACTIVE, start, end, active }; }, reorderAction(actionId: number, beforeActionId: number): ReorderAction { return { type: ActionTypes.REORDER_ACTION, actionId, beforeActionId }; }, jumpToState(index: number): JumpToStateAction { return { type: ActionTypes.JUMP_TO_STATE, index }; }, jumpToAction(actionId: number): JumpToActionAction { return { type: ActionTypes.JUMP_TO_ACTION, actionId }; }, importState, MonitorState = null>( nextLiftedState: LiftedState | readonly A[], noRecompute?: boolean ): ImportStateAction { return { type: ActionTypes.IMPORT_STATE, nextLiftedState, noRecompute }; }, lockChanges(status: boolean): LockChangesAction { return { type: ActionTypes.LOCK_CHANGES, status }; }, pauseRecording(status: boolean): PauseRecordingAction { return { type: ActionTypes.PAUSE_RECORDING, status }; }, }; export const INIT_ACTION = { type: '@@INIT' }; /** * Computes the next entry with exceptions catching. */ function computeWithTryCatch>( reducer: Reducer, action: A, state: S ) { let nextState = state; let nextError; try { nextState = reducer(state, action); } catch (err) { // eslint-disable-next-line @typescript-eslint/ban-types nextError = (err as object).toString(); if (isChrome) { // In Chrome, rethrowing provides better source map support setTimeout(() => { throw err; }); } else { console.error(err); // eslint-disable-line no-console } } return { state: nextState, error: nextError, }; } /** * Computes the next entry in the log by applying an action. */ function computeNextEntry>( reducer: Reducer, action: A, state: S, shouldCatchErrors: boolean | undefined ) { if (!shouldCatchErrors) { return { state: reducer(state, action) }; } return computeWithTryCatch(reducer, action, state); } /** * Runs the reducer on invalidated actions to get a fresh computation log. */ function recomputeStates>( computedStates: { state: S; error?: string }[], minInvalidatedStateIndex: number, reducer: Reducer, committedState: S, actionsById: { [actionId: number]: PerformAction }, stagedActionIds: number[], skippedActionIds: number[], shouldCatchErrors: boolean | undefined ) { // Optimization: exit early and return the same reference // if we know nothing could have changed. if ( !computedStates || minInvalidatedStateIndex === -1 || (minInvalidatedStateIndex >= computedStates.length && computedStates.length === stagedActionIds.length) ) { return computedStates; } const nextComputedStates = computedStates.slice(0, minInvalidatedStateIndex); for (let i = minInvalidatedStateIndex; i < stagedActionIds.length; i++) { const actionId = stagedActionIds[i]; const action = actionsById[actionId].action; const previousEntry = nextComputedStates[i - 1]; const previousState = previousEntry ? previousEntry.state : committedState; const shouldSkip = skippedActionIds.indexOf(actionId) > -1; let entry; if (shouldSkip) { entry = previousEntry; } else { if (shouldCatchErrors && previousEntry && previousEntry.error) { entry = { state: previousState, error: 'Interrupted by an error up the chain', }; } else { entry = computeNextEntry( reducer, action, previousState, shouldCatchErrors ); } } nextComputedStates.push(entry); } return nextComputedStates; } /** * Lifts an app's action into an action on the lifted store. */ export function liftAction>( action: A, trace?: ((action: A) => string | undefined) | boolean, traceLimit?: number, // eslint-disable-next-line @typescript-eslint/ban-types toExcludeFromTrace?: Function ) { return ActionCreators.performAction( action, trace, traceLimit, toExcludeFromTrace ); } function isArray, MonitorState>( nextLiftedState: LiftedState | readonly A[] ): nextLiftedState is readonly A[] { return Array.isArray(nextLiftedState); } export interface LiftedState, MonitorState> { monitorState: MonitorState; nextActionId: number; actionsById: { [actionId: number]: PerformAction }; stagedActionIds: number[]; skippedActionIds: number[]; committedState: S; currentStateIndex: number; computedStates: { state: S; error?: string }[]; isLocked: boolean; isPaused: boolean; } /** * Creates a history state reducer from an app's reducer. */ export function liftReducerWith< S, A extends Action, MonitorState, MonitorAction extends Action >( reducer: Reducer, initialCommittedState: PreloadedState | undefined, monitorReducer: Reducer, options: Options ): Reducer, LiftedAction> { const initialLiftedState: LiftedState = { monitorState: monitorReducer(undefined, {} as MonitorAction), nextActionId: 1, actionsById: { 0: liftAction(INIT_ACTION as A) }, stagedActionIds: [0], skippedActionIds: [], committedState: initialCommittedState as S, currentStateIndex: 0, computedStates: [], isLocked: options.shouldStartLocked === true, isPaused: options.shouldRecordChanges === false, }; /** * Manages how the history actions modify the history state. */ return ( liftedState: LiftedState | undefined, liftedAction: LiftedAction ): LiftedState => { let { monitorState, actionsById, nextActionId, stagedActionIds, skippedActionIds, committedState, currentStateIndex, computedStates, isLocked, isPaused, } = liftedState || initialLiftedState; if (!liftedState) { // Prevent mutating initialLiftedState actionsById = { ...actionsById }; } function commitExcessActions(n: number) { // Auto-commits n-number of excess actions. let excess = n; let idsToDelete = stagedActionIds.slice(1, excess + 1); for (let i = 0; i < idsToDelete.length; i++) { if (computedStates[i + 1].error) { // Stop if error is found. Commit actions up to error. excess = i; idsToDelete = stagedActionIds.slice(1, excess + 1); break; } else { delete actionsById[idsToDelete[i]]; } } skippedActionIds = skippedActionIds.filter( (id) => idsToDelete.indexOf(id) === -1 ); stagedActionIds = [0, ...stagedActionIds.slice(excess + 1)]; committedState = computedStates[excess].state; computedStates = computedStates.slice(excess); currentStateIndex = currentStateIndex > excess ? currentStateIndex - excess : 0; } function computePausedAction( shouldInit?: boolean ): LiftedState { let computedState; if (shouldInit) { computedState = computedStates[currentStateIndex]; monitorState = monitorReducer( monitorState, liftedAction as MonitorAction ); } else { computedState = computeNextEntry( reducer, (liftedAction as PerformAction).action, computedStates[currentStateIndex].state, false ); } if (!options.pauseActionType || nextActionId === 1) { return { monitorState, actionsById: { 0: liftAction(INIT_ACTION as A) }, nextActionId: 1, stagedActionIds: [0], skippedActionIds: [], committedState: computedState.state, currentStateIndex: 0, computedStates: [computedState], isLocked, isPaused: true, }; } if (shouldInit) { if (currentStateIndex === stagedActionIds.length - 1) { currentStateIndex++; } stagedActionIds = [...stagedActionIds, nextActionId]; nextActionId++; } return { monitorState, actionsById: { ...actionsById, [nextActionId - 1]: liftAction({ type: options.pauseActionType, } as A), }, nextActionId, stagedActionIds, skippedActionIds, committedState, currentStateIndex, computedStates: [ ...computedStates.slice(0, stagedActionIds.length - 1), computedState, ], isLocked, isPaused: true, }; } // By default, aggressively recompute every state whatever happens. // This has O(n) performance, so we'll override this to a sensible // value whenever we feel like we don't have to recompute the states. let minInvalidatedStateIndex = 0; // maxAge number can be changed dynamically let maxAge = options.maxAge; if (typeof maxAge === 'function') maxAge = maxAge(liftedAction, liftedState); if (/^@@redux\/(INIT|REPLACE)/.test(liftedAction.type)) { if (options.shouldHotReload === false) { actionsById = { 0: liftAction(INIT_ACTION as A) }; nextActionId = 1; stagedActionIds = [0]; skippedActionIds = []; committedState = computedStates.length === 0 ? (initialCommittedState as S) : computedStates[currentStateIndex].state; currentStateIndex = 0; computedStates = []; } // Recompute states on hot reload and init. minInvalidatedStateIndex = 0; if (maxAge && stagedActionIds.length > maxAge) { // States must be recomputed before committing excess. computedStates = recomputeStates( computedStates, minInvalidatedStateIndex, reducer, committedState, actionsById, stagedActionIds, skippedActionIds, options.shouldCatchErrors ); commitExcessActions(stagedActionIds.length - maxAge); // Avoid double computation. minInvalidatedStateIndex = Infinity; } } else { switch (liftedAction.type) { case ActionTypes.PERFORM_ACTION: { if (isLocked) return liftedState || initialLiftedState; if (isPaused) return computePausedAction(); // Auto-commit as new actions come in. if (maxAge && stagedActionIds.length >= maxAge) { commitExcessActions(stagedActionIds.length - maxAge + 1); } if (currentStateIndex === stagedActionIds.length - 1) { currentStateIndex++; } const actionId = nextActionId++; // Mutation! This is the hottest path, and we optimize on purpose. // It is safe because we set a new key in a cache dictionary. actionsById[actionId] = liftedAction; stagedActionIds = [...stagedActionIds, actionId]; // Optimization: we know that only the new action needs computing. minInvalidatedStateIndex = stagedActionIds.length - 1; break; } case ActionTypes.RESET: { // Get back to the state the store was created with. actionsById = { 0: liftAction(INIT_ACTION as A) }; nextActionId = 1; stagedActionIds = [0]; skippedActionIds = []; committedState = initialCommittedState as S; currentStateIndex = 0; computedStates = []; break; } case ActionTypes.COMMIT: { // Consider the last committed state the new starting point. // Squash any staged actions into a single committed state. actionsById = { 0: liftAction(INIT_ACTION as A) }; nextActionId = 1; stagedActionIds = [0]; skippedActionIds = []; committedState = computedStates[currentStateIndex].state; currentStateIndex = 0; computedStates = []; break; } case ActionTypes.ROLLBACK: { // Forget about any staged actions. // Start again from the last committed state. actionsById = { 0: liftAction(INIT_ACTION as A) }; nextActionId = 1; stagedActionIds = [0]; skippedActionIds = []; currentStateIndex = 0; computedStates = []; break; } case ActionTypes.TOGGLE_ACTION: { // Toggle whether an action with given ID is skipped. // Being skipped means it is a no-op during the computation. const { id: actionId } = liftedAction; const index = skippedActionIds.indexOf(actionId); if (index === -1) { skippedActionIds = [actionId, ...skippedActionIds]; } else { skippedActionIds = skippedActionIds.filter((id) => id !== actionId); } // Optimization: we know history before this action hasn't changed minInvalidatedStateIndex = stagedActionIds.indexOf(actionId); break; } case ActionTypes.SET_ACTIONS_ACTIVE: { // Toggle whether an action with given ID is skipped. // Being skipped means it is a no-op during the computation. const { start, end, active } = liftedAction; const actionIds = []; for (let i = start; i < end; i++) actionIds.push(i); if (active) { skippedActionIds = difference(skippedActionIds, actionIds); } else { skippedActionIds = union(skippedActionIds, actionIds); } // Optimization: we know history before this action hasn't changed minInvalidatedStateIndex = stagedActionIds.indexOf(start); break; } case ActionTypes.JUMP_TO_STATE: { // Without recomputing anything, move the pointer that tell us // which state is considered the current one. Useful for sliders. currentStateIndex = liftedAction.index; // Optimization: we know the history has not changed. minInvalidatedStateIndex = Infinity; break; } case ActionTypes.JUMP_TO_ACTION: { // Jumps to a corresponding state to a specific action. // Useful when filtering actions. const index = stagedActionIds.indexOf(liftedAction.actionId); if (index !== -1) currentStateIndex = index; minInvalidatedStateIndex = Infinity; break; } case ActionTypes.SWEEP: { // Forget any actions that are currently being skipped. stagedActionIds = difference(stagedActionIds, skippedActionIds); skippedActionIds = []; currentStateIndex = Math.min( currentStateIndex, stagedActionIds.length - 1 ); break; } case ActionTypes.REORDER_ACTION: { // Recompute actions in a new order. const actionId = liftedAction.actionId; const idx = stagedActionIds.indexOf(actionId); // do nothing in case the action is already removed or trying to move the first action if (idx < 1) break; const beforeActionId = liftedAction.beforeActionId; let newIdx = stagedActionIds.indexOf(beforeActionId); if (newIdx < 1) { // move to the beginning or to the end const count = stagedActionIds.length; newIdx = beforeActionId > stagedActionIds[count - 1] ? count : 1; } const diff = idx - newIdx; if (diff > 0) { // move left stagedActionIds = [ ...stagedActionIds.slice(0, newIdx), actionId, ...stagedActionIds.slice(newIdx, idx), ...stagedActionIds.slice(idx + 1), ]; minInvalidatedStateIndex = newIdx; } else if (diff < 0) { // move right stagedActionIds = [ ...stagedActionIds.slice(0, idx), ...stagedActionIds.slice(idx + 1, newIdx), actionId, ...stagedActionIds.slice(newIdx), ]; minInvalidatedStateIndex = idx; } break; } case ActionTypes.IMPORT_STATE: { if (isArray(liftedAction.nextLiftedState)) { // recompute array of actions actionsById = { 0: liftAction(INIT_ACTION as A) }; nextActionId = 1; stagedActionIds = [0]; skippedActionIds = []; currentStateIndex = liftedAction.nextLiftedState.length; computedStates = []; committedState = liftedAction.preloadedState as S; minInvalidatedStateIndex = 0; // iterate through actions liftedAction.nextLiftedState.forEach((action) => { actionsById[nextActionId] = liftAction( action, options.trace || options.shouldIncludeCallstack ); stagedActionIds.push(nextActionId); nextActionId++; }); } else { // Completely replace everything. ({ monitorState, actionsById, nextActionId, stagedActionIds, skippedActionIds, committedState, currentStateIndex, computedStates, } = liftedAction.nextLiftedState); if (liftedAction.noRecompute) { minInvalidatedStateIndex = Infinity; } } break; } case ActionTypes.LOCK_CHANGES: { isLocked = liftedAction.status; minInvalidatedStateIndex = Infinity; break; } case ActionTypes.PAUSE_RECORDING: { isPaused = liftedAction.status; if (isPaused) { return computePausedAction(true); } // Commit when unpausing actionsById = { 0: liftAction(INIT_ACTION as A) }; nextActionId = 1; stagedActionIds = [0]; skippedActionIds = []; committedState = computedStates[currentStateIndex].state; currentStateIndex = 0; computedStates = []; break; } default: { // If the action is not recognized, it's a monitor action. // Optimization: a monitor action can't change history. minInvalidatedStateIndex = Infinity; break; } } } computedStates = recomputeStates( computedStates, minInvalidatedStateIndex, reducer, committedState, actionsById, stagedActionIds, skippedActionIds, options.shouldCatchErrors ); monitorState = monitorReducer(monitorState, liftedAction as MonitorAction); return { monitorState, actionsById, nextActionId, stagedActionIds, skippedActionIds, committedState, currentStateIndex, computedStates, isLocked, isPaused, }; }; } /** * Provides an app's view into the state of the lifted store. */ export function unliftState< S, A extends Action, MonitorState, NextStateExt >( liftedState: LiftedState & NextStateExt ): S & NextStateExt { const { computedStates, currentStateIndex } = liftedState; const { state } = computedStates[currentStateIndex]; return state as S & NextStateExt; } export type LiftedReducer, MonitorState> = Reducer< LiftedState, LiftedAction >; export type LiftedStore, MonitorState> = Store< LiftedState, LiftedAction >; export type InstrumentExt, MonitorState> = { liftedStore: LiftedStore; }; export type EnhancedStore, MonitorState> = Store< S, A > & InstrumentExt; /** * Provides an app's view into the lifted store. */ export function unliftStore< S, A extends Action, MonitorState, MonitorAction extends Action, NextExt, NextStateExt >( liftedStore: Store< LiftedState & NextStateExt, LiftedAction > & NextExt, liftReducer: (r: Reducer) => LiftedReducer, options: Options ) { let lastDefinedState: S & NextStateExt; const trace = options.trace || options.shouldIncludeCallstack; const traceLimit = options.traceLimit || 10; function getState(): S & NextStateExt { const state = unliftState( liftedStore.getState() ); if (state !== undefined) { lastDefinedState = state; } return lastDefinedState; } function dispatch(action: T): T { liftedStore.dispatch(liftAction(action, trace, traceLimit, dispatch)); return action; } return { ...liftedStore, liftedStore, dispatch, getState, replaceReducer(nextReducer: Reducer) { liftedStore.replaceReducer( liftReducer( nextReducer as unknown as Reducer ) as unknown as Reducer< LiftedState & NextStateExt, LiftedAction > ); }, [$$observable](): Observable { return { ...(liftedStore as any)[$$observable](), subscribe(observer) { if (typeof observer !== 'object') { throw new TypeError('Expected the observer to be an object.'); } function observeState() { if (observer.next) { observer.next(getState()); } } observeState(); const unsubscribe = liftedStore.subscribe(observeState); return { unsubscribe }; }, [$$observable]() { return this; }, }; }, } as unknown as Store & NextExt & { liftedStore: Store< LiftedState & NextStateExt, LiftedAction >; }; } export interface Options< S, A extends Action, MonitorState, MonitorAction extends Action > { maxAge?: | number | (( currentLiftedAction: LiftedAction, previousLiftedState: LiftedState | undefined ) => number); shouldCatchErrors?: boolean; shouldRecordChanges?: boolean; pauseActionType?: unknown; shouldStartLocked?: boolean; shouldHotReload?: boolean; trace?: boolean | ((action: A) => string | undefined); traceLimit?: number; shouldIncludeCallstack?: boolean; } /** * Redux instrumentation store enhancer. */ export default function instrument< OptionsS, OptionsA extends Action, MonitorState = null, MonitorAction extends Action = never >( monitorReducer: Reducer = (() => null) as unknown as Reducer, options: Options = {} ): StoreEnhancer> { if (typeof options.maxAge === 'number' && options.maxAge < 2) { throw new Error( 'DevTools.instrument({ maxAge }) option, if specified, ' + 'may not be less than 2.' ); } return ( createStore: StoreEnhancerStoreCreator ) => >( reducer: Reducer, initialState?: PreloadedState ) => { function liftReducer(r: Reducer) { if (typeof r !== 'function') { if (r && typeof (r as { default: unknown }).default === 'function') { throw new Error( 'Expected the reducer to be a function. ' + 'Instead got an object with a "default" field. ' + 'Did you pass a module instead of the default export? ' + 'Try passing require(...).default instead.' ); } throw new Error('Expected the reducer to be a function.'); } return liftReducerWith( r, initialState, monitorReducer, options as unknown as Options ); } const liftedStore = createStore(liftReducer(reducer)); if ( ( liftedStore as Store< LiftedState & NextStateExt, LiftedAction > & NextExt & { liftedStore: Store< LiftedState, LiftedAction >; } ).liftedStore ) { throw new Error( 'DevTools instrumentation should not be applied more than once. ' + 'Check your store configuration.' ); } return unliftStore< S, A, MonitorState, MonitorAction, NextExt, NextStateExt >( liftedStore, liftReducer, options as unknown as Options ); }; }