test(`Interval.plus() doesn't mofify operands`, () => {

    const { int1, int2 } = ['2:28', '2:29.1'].map(s => Interval.fromString(s));
    const s1 = int1.toString();
    const s2 = int2.toString();

    int1.plus(int2);

    expect(int1.toString()).toBe(s1);
    expect(int2.toString()).toBe(s2);

  });

class Test {
  constructor () {
    this._value = 1
  }

  methodA () {
    console.log('methodA')
    this._value = 2
    return true
  }

  methodB () {
    console.log('methodB')
    return true
  }
}

const instance = new Test()
const proxy = new Proxy(instance, {
  set: (obj, prop, value) => {
    console.log('trying to change the value')
    return Reflect.set(obj, prop, value)
  }
})

proxy.methodA()
proxy.methodB()
console.log('change directly')
proxy._value = 3