@jedmao/redux-mock-store/dist/esm/index.js

A mock store for testing your redux async action creators and middleware

import { applyMiddleware, } from 'redux';
import { isFunction, isPlainObject } from './utils';
/**
 * A mock store for testing Redux async action creators and middleware.
 */
export function configureMockStore(middlewares = []) {
    return mockStore;
    /**
     * @returns An instance of the configured mock store.
     * @note Call this function to reset your store after every test.
     */
    function mockStore(getState = {}) {
        return applyMiddleware(...middlewares)(creator)(undefined);
        function creator() {
            let actions = [];
            const listeners = [];
            return {
                getState() {
                    return isFunction(getState) ? getState(actions) : getState;
                },
                getActions() {
                    return actions;
                },
                clearActions() {
                    actions = [];
                },
                dispatch(action) {
                    if (!isPlainObject(action)) {
                        throw new TypeError('Actions must be plain objects. ' +
                            'Use custom middleware for async actions.');
                    }
                    if (typeof action.type === 'undefined') {
                        throw new TypeError('Actions may not have an undefined "type" property. ' +
                            'Have you misspelled a constant? ' +
                            'Action: ' +
                            JSON.stringify(action));
                    }
                    actions.push(action);
                    for (const listener of listeners) {
                        listener(action);
                    }
                    return action;
                },
                subscribe(listener) {
                    if (!isFunction(listener)) {
                        throw new TypeError('Listener must be a function.');
                    }
                    listeners.push(listener);
                    return unsubscribe;
                    function unsubscribe() {
                        const index = listeners.indexOf(listener);
                        if (index === -1) {
                            return;
                        }
                        listeners.splice(index, 1);
                    }
                },
                // eslint-disable-next-line @typescript-eslint/no-unused-vars
                replaceReducer(_nextReducer) {
                    throw new Error('Mock stores do not support reducers. ' +
                        'Try supplying a function to getStore instead.');
                },
                /* istanbul ignore next */
                [Symbol.observable]() {
                    throw new Error('Not implemented');
                },
            };
        }
    }
}