vue.js __ob__ (Observer) lost

[ibyteyou]

analogue #76

need reproduction?
maybe it's must be controlled for performance? re clone option?
as expected { clone: true } must repeat this behavior,
and { clone: false } must save alias __ob__

[TehShrike]

deepmerge uses Object.keys to iterate over properties:

https://github.com/KyleAMathews/deepmerge/blob/0f5efc82da76c6aed892131a11bb967e86cd9717/index.js#L22

Object.keys only iterates over properties that are

• enumerable
• on the object directly, as opposed to somewhere up the prototype chain

I'm going to guess that __ob__ doesn't meet one of those checks.

[TehShrike]

(You can use propertyIsEnumerable and hasOwnProperty to confirm)

[ibyteyou]

@TehShrike

__ob__.propertyIsEnumerable() => false
__ob__.hasOwnProperty() => false

[ibyteyou]

internal structure of __ob__:

Observer {
  dep: Dep {
    id: 16650
    subs: [] // array with vue reactive dependences
  },
  value: {}, // alias to root
  vmCount: 0
}

[TehShrike]

The syntax is

vueReactiveData.propertyIsEnumerable('__ob__')
vueReactiveData.hasOwnProperty('__ob__')

See the docs

• https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/propertyIsEnumerable
• https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/hasOwnProperty

[ibyteyou]

oh 😛sorry)

propertyIsEnumerable('__ob__') => false
hasOwnProperty('__ob__') => true