Jest期望一个内部有函数的对象

Question

我正在编写一个Jest测试，在该测试中我调用一个函数并期望返回一个对象，如下所示：

const repository = container => {
const makeBooking = (user, booking) => {
'make booking function called'
}
const generateTicket = (paid, booking) => {
console.log('generate ticket function called')
}
const getOrderById = orderId => {
console.log('get order by ID called')
}
const disconnect = () => {
console.log('disconnect method called')
}
return {
makeBooking,
getOrderById,
generateTicket,
disconnect
}
}

为了举例说明，所有这些函数现在都是示例。我现在，导出函数，然后在测试中使用它，如下所示：

container = {}
describe('Repository', () => {
it('should connect with a container', () => {
let hello = repository(container)
expect(hello).toMatchObject({
makeBooking: jest.fn('makeBooking'),
getOrderById: jest.fn('getOrderById'),
generateTicket: jest.fn('generateTicket'),
disconnect: jest.fn('disconnect')
})
})
})

我得到的错误是：

Expected value to match object:
{"disconnect": [Function mockConstructor], "generateTicket": [Function mockConstructor], "getOrderById": [Function mockConstructor], "makeBooking": [Function mockConstructor]}
Received:
{"disconnect": [Function disconnect], "generateTicket": [Function generateTicket], "getOrderById": [Function getOrderById], "makeBooking": [Function makeBooking]}

我需要模拟从存储库对象返回的对象。但是，该对象由代码中所示的命名函数组成。有没有任何东西可以模拟里面有函数的对象？

Answer 1

这就是我想要的：

expect.objectContaining({ 
theProperty: expect.any(Function) 
})

Answer 2

您可以使用jest.spyOn为repository的方法制作存根。

您模拟或存根存储库的方法，您需要使用它们。这就是service.js的来源，当然，您可以在任何地方使用存储库。所以，实际上要测试的方法是service.makeBooking。然后，您可以对存储库的makeBooking方法进行断言，例如，检查存储库的模拟/存根makeBooking方法是否已被调用。

这里我们使用依赖注入模式将模拟的hello对象注入到service.makeBooking(hello)方法中。

例如

repository.js:

const repository = (container) => {
const makeBooking = (user, booking) => {
'make booking function called';
};
const generateTicket = (paid, booking) => {
console.log('generate ticket function called');
};
const getOrderById = (orderId) => {
console.log('get order by ID called');
};
const disconnect = () => {
console.log('disconnect method called');
};
return {
makeBooking,
getOrderById,
generateTicket,
disconnect,
};
};
module.exports = repository;

repository.test.js:

const repository = require('./repository');
const container = {};
describe('Repository', () => {
it('should connect with a container', () => {
let hello = repository(container);
expect(hello).toMatchObject({
makeBooking: expect.any(Function),
getOrderById: expect.any(Function),
generateTicket: expect.any(Function),
disconnect: expect.any(Function),
});
});
it('should generate ticket', () => {
let hello = repository(container);
const logSpy = jest.spyOn(console, 'log');
hello.generateTicket();
expect(logSpy).toBeCalledWith('generate ticket function called');
});
// rest test cases same as above
});

带覆盖率报告的单元测试结果：

PASS  stackoverflow/61268658/repository.test.js (11.281s)
Repository
✓ should connect with a container (5ms)
✓ should generate ticket (19ms)
console.log node_modules/jest-environment-enzyme/node_modules/jest-mock/build/index.js:866
generate ticket function called
---------------|---------|----------|---------|---------|-------------------
File           | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s 
---------------|---------|----------|---------|---------|-------------------
All files      |      80 |      100 |      40 |      80 |                   
repository.js |      80 |      100 |      40 |      80 | 11,15             
---------------|---------|----------|---------|---------|-------------------
Test Suites: 1 passed, 1 total
Tests:       2 passed, 2 total
Snapshots:   0 total
Time:        13.132s

service.js:

const service = {
makeBooking(hello) {
return hello.makeBooking();
},
};
module.exports = service;

service.test.js:

const service = require('./service');
const repository = require('./repository');
const container = {};
describe('service', () => {
it('should init', () => {
let hello = repository(container);
jest.spyOn(hello, 'makeBooking').mockReturnValueOnce('fake data');
const actual = service.makeBooking(hello);
expect(actual).toEqual('fake data');
expect(hello.makeBooking).toBeCalledTimes(1);
});
});

带覆盖率报告的单元测试结果：

PASS  stackoverflow/61268658/service.test.js (10.94s)
service
✓ should init (4ms)
---------------|---------|----------|---------|---------|-------------------
File           | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s 
---------------|---------|----------|---------|---------|-------------------
All files      |   76.92 |      100 |   33.33 |   76.92 |                   
repository.js |      70 |      100 |      20 |      70 | 7,11,15           
service.js    |     100 |      100 |     100 |     100 |                   
---------------|---------|----------|---------|---------|-------------------
Test Suites: 1 passed, 1 total
Tests:       1 passed, 1 total
Snapshots:   0 total
Time:        12.278s