如何在TS中存根全局函数

Question

这是我的TS课

function func3(): string {  
  return ' some string'
}

function func4(){
  func3()
}

export class classA implements ImyInterface {
  public func1(): void { func4() }
  public func2(): void {}
}

现在，我想编写测试以调用func1然后模拟func3不能与存根一起使用。

sandbox.stub(myInstance,"test3").returns("data");

如果我将func3移到classA，则func4找不到该类

Answer 1

这里是单元测试解决方案：

index.ts：

function func3(): string {
  return 'some string';
}

function func4() {
  const rval = exports.func3();
  console.log(rval);
}
interface ImyInterface {}

class classA implements ImyInterface {
  public func1(): void {
    exports.func4();
  }
  public func2(): void {}
}

exports.func3 = func3;
exports.func4 = func4;
exports.classA = classA;

index.spec.ts：

import { expect } from 'chai';
import sinon from 'sinon';

const mod = require('./');

describe('t', () => {
  it('should call stubbed methods correctly', () => {
    const func3Stub = sinon.stub(mod, 'func3').returns('data');
    const func4Spy = sinon.spy(mod, 'func4');
    const logSpy = sinon.spy(console, 'log');
    const instance = new mod.classA();
    instance.func1();
    expect(func4Spy.calledOnce).to.be.true;
    expect(func3Stub.calledOnce).to.be.true;
    expect(logSpy.calledWith('data')).to.be.true;
  });
});

带有覆盖率报告的单元测试结果：

 t
data
    ✓ should call stubbed methods correctly


  1 passing (16ms)

---------------|----------|----------|----------|----------|-------------------|
File           |  % Stmts | % Branch |  % Funcs |  % Lines | Uncovered Line #s |
---------------|----------|----------|----------|----------|-------------------|
All files      |    95.83 |      100 |    71.43 |    95.83 |                   |
 index.spec.ts |      100 |      100 |      100 |      100 |                   |
 index.ts      |    90.91 |      100 |       60 |    90.91 |                 2 |
---------------|----------|----------|----------|----------|-------------------|

源代码：https://github.com/mrdulin/mocha-chai-sinon-codelab/tree/master/src/stackoverflow/57589200