目标

it('isRef', () => {
  const a = ref(1);
  const user = reactive({ age: 1 });
  expect(isRef(a)).toBe(true);
  expect(isRef(1)).toBe(false);
  expect(isRef(user)).toBe(false);
});
it('unRef', () => {
  const a = ref(1);
  expect(unRef(a)).toBe(1);
  expect(unRef(1)).toBe(1);
});

isRef 实现

使用一个 __v_isRef的 flag

class RefImpl {
  private _value: any;
  private _rawValue: any;
  // 是不是 ref 的标识
  public __v_isRef = true;
  public dep;
  constructor(value) {
    this._rawValue = value;
    this._value = convert(value);
    this.dep = new Set();
  }
  get value() {
    trackRefValue(this);
    return this._value;
  }
  set value(newValue) {
    if (hasChange(newValue, this._rawValue)) {
      this._rawValue = newValue;
      this._value = convert(newValue);
      triggerEffect(this.dep);
    }
  }
}
export function isRef(ref) {
  return !!ref.__v_isRef;
}

unRef 实现

export funciton unRef(ref) {
  // 看看是不是 ref，是就返回 ref.value，否则直接返回 ref
  return isRef(ref) ? ref.value : ref;
}