模擬store.getState（）

Question

我想斷言，當一個函數使用store.getState()獲取我的redux狀態值時，它會根據該狀態的條件執行各種操作。 如何使用store.getState()方法來斷言/模擬某些測試的狀態值？ 謝謝。

sampleFunction.js：

import { store } from './reduxStore';

const sampleFunction = () => {
  const state = store.getState();
  let result = false;
  if (state.foo.isGood) {
    result = true;
  }

  return result;
};

export default sampleFunction;

sampleFunction.test.js：

import sampleFunction from './sampleFunction.js';

test('sampleFunction returns true', () => {
  // assert that state.foo.isGood = true
  expect(sampleFunction()).toBeTruthy();
});

Answer 1

您可以模擬商店的方法是

import { store } from './reduxStore';
import sampleFunction from './sampleFunction.js';

jest.mock('./reduxStore')

const mockState = {
  foo: { isGood: true }
}

// in this point store.getState is going to be mocked
store.getState = () => mockState

test('sampleFunction returns true', () => {
  // assert that state.foo.isGood = true
  expect(sampleFunction()).toBeTruthy();
});