Function defineAccessControl

src/reactivity/reactive.ts:65–114

(target: AnyObject, key: any, val?: any)

 * Auto unwrapping when access property
 */
export function defineAccessControl(target: AnyObject, key: any, val?: any) {
  if (key === '__ob__') return
  if (isRaw(target[key])) return

  let getter: (() => any) | undefined
  let setter: ((x: any) => void) | undefined
  const property = Object.getOwnPropertyDescriptor(target, key)
  if (property) {
    if (property.configurable === false) {
      return
    }
    getter = property.get
    setter = property.set
    if (
      (!getter || setter) /* not only have getter */ &&
      arguments.length === 2
    ) {
      val = target[key]
    }
  }

  setupAccessControl(val)
  proxy(target, key, {
    get: function getterHandler() {
      const value = getter ? getter.call(target) : val
      // if the key is equal to RefKey, skip the unwrap logic
      if (key !== RefKey && isRef(value)) {
        return value.value
      } else {
        return value
      }
    },
    set: function setterHandler(newVal: any) {
      if (getter && !setter) return

      // If the key is equal to RefKey, skip the unwrap logic
      // If and only if "value" is ref and "newVal" is not a ref,
      // the assignment should be proxied to "value" ref.
      if (key !== RefKey && isRef(val) && !isRef(newVal)) {
        val.value = newVal
      } else if (setter) {
        setter.call(target, newVal)
        val = newVal
      } else {
        val = newVal
      }
      setupAccessControl(newVal)
    },
  })
}

export function observe<T>(obj: T): T {
  const Vue = getRegisteredVueOrDefault()