Describe references as such

[Marsup]

As mentioned in outmoded/lout#57, references should have their own descriptions.

> Joi.compile(Joi.ref('a.b')).describe()
{ type: 'any',
  flags: { allowOnly: true },
  valids:
   [ undefined,
     { [Function]
       isContext: false,
       key: 'a.b',
       path: [Object],
       depth: 2,
       root: 'a',
       isJoi: true,
       toString: [Function] } ],
  invalids: [ null ] }

I think isContext, key, path, depth, root should be exposed at the root of the description and type should indeed be ref.

[hueniverse]

Example?

[Marsup]

{
  type: 'ref',
  isContext: false,
  key: 'a.b'
  path: ['a', 'b'],
  depth: 2,
  root: 'a'
}

Not sure about valids/invalids, can they ever have other values ?

[hueniverse]

Valid and invalid cannot be an object or function other than: null, undefined, Date, Buffer, or Ref. So making it an object is safe. However, also need to figure out default() which takes anything. Should I just expose Ref.isRef() as an API and leave it as is?

[Marsup]

Considering the specific api of refs, I don't see how valids could ever be anything else than [undefined, function] and invalids [null], am I wrong ?
isRef would only help me detect which function in valids is the one to extract information from, I'd rather have it exposed right away without having to dig through valids, don't you think ?

[hueniverse]

Valid and invalid is easy to do. What do you want to do about flags.default?

[Marsup]

Does it exist at all ?

> Joi.ref('a.b').default(0)
TypeError: Object ref:a.b has no method 'default'

[hueniverse]

No. Joi.any().default(Joi.ref('a.b'))

[Marsup]

I think it's out of topic. My current problem is to describe references alone, not objects of any type that have a default to a reference. Unless I missed something I don't see how it's related.

[hueniverse]

Yeah, but it's the same problem for me.

[hueniverse]

I've decided to leave the describe() behavior as-is, and add Joi.isRef(). Right now, in valids and invalids a function can only be a ref, but this may change in the future. flags.default can be anything. If a value is a function, just call Joi.isRef() on it to find out.