CurrentUser

    import StorageFactoryModule from 'app/common/services/StorageFactory';
    
    class CurrentUser {
    	constructor(StorageFactory) {

		this.storageKey = 'appUser';

		this.StorageFactory = StorageFactory;

		this.profile = initializeUser.call(this);

		function initializeUser() {
			var userFromStorage = StorageFactory.get(this.storageKey);
			if (userFromStorage != null) {
				return userFromStorage;
			} else {
				// return default user
			}
		}

	}
    // more methods, that are removed for brevity

    }
    
    CurrentUser.$inject = ['StorageFactory'];
    
    export default angular.module('CurrentUserModule', [StorageFactoryModule.name])
    	.service('CurrentUser', CurrentUser);

CurrentUser.spec.js

import angular from 'angular';
import 'angular-mocks';
import './CurrentUser';

describe('CurrentUser', function () {
	"use strict";
	var user = {userid: 'abc', token: 'token'};

	var storageFactoryMock = {
		get: function (key) {
			console.log('mocked get');
			return user;
		},
		put: function (key, newUser) {
			console.log('mocked put');
			user = newUser;
		},
		remove: function (key) {
			console.log('mocked remove');
			user = undefined;
		}
	};

	beforeEach(function () {
		angular.module('StorageFactoryModule')
			.value('StorageFactory', storageFactoryMock);
		angular.mock.module('CurrentUserModule');
	});

	it('should Initialize User from local storage if already exists there', inject(function (CurrentUser) {
		expect(CurrentUser.profile).toEqual(user);
	}))
});