jest.doMock和JSON导入模拟

jest.doMock(moduleName, factory, options);

// foo.js
const bar = require('./bar');

function foo() {
  return bar();
}

module.exports = foo;

// bar.js
function bar() {
  return 'Hello, World!';
}

module.exports = bar;

// foo.test.js
const jest = require('jest');
const foo = require('./foo');

jest.doMock('./bar', () => jest.fn(() => 'Mocked bar function'));

test('should mock the bar module', () => {
  expect(foo()).toBe('Mocked bar function');
});

jest.mock(moduleName, factory, options);

// config.js
const config = require('./config.json');

function getConfig() {
  return config;
}

module.exports = getConfig;

// config.json
{
  "apiUrl": "https://example.com/api",
  "apiKey": "1234567890"
}

// config.test.js
const jest = require('jest');
const getConfig = require('./config');

jest.mock('./config.json', () => ({
  apiUrl: 'https://mocked-api.com',
  apiKey: '0987654321'
}));

test('should mock the config', () => {
  expect(getConfig()).toEqual({
    apiUrl: 'https://mocked-api.com',
    apiKey: '0987654321'
  });
});