Jasmine 2.x Mock Local Storage

This will add two functions mockLocalStorage() and unmockLocalStorage()

Install

npm install --save-dev jasmine-local-storage

// in your jasmine helpers file
require("jasmine-local-storage");

Usage

beforeEach(function () {
  mockLocalStorage();
});

it("will not write to actual localStorage", function () {
  unmockLocalStorage();

  localStorage.setItem("test", 1);
  expect(localStorage.getItem("test")).toBe("1");

  mockLocalStorage();

  localStorage.setItem("test", 2);
  expect(localStorage.getItem("test")).toBe("2");
  expect(localStorage.key(0)).toBe("test");
  localStorage.removeItem("test");
  expect(localStorage.getItem("test")).toBe(null);

  expect(localStorage.setItem).toHaveBeenCalledTimes(1);
  expect(localStorage.getItem).toHaveBeenCalledTimes(1);
  expect(localStorage.removeItem).toHaveBeenCalledTimes(1);
  expect(localStorage.key).toHaveBeenCalledTimes(1);
  expect(localStorage.clear).toHaveBeenCalledTimes(0);

  unmockLocalStorage();

  expect(localStorage.getItem("test")).toBe("1");
  localStorage.removeItem("test");
});