JsError extractors

[cchantep]

Pull Request Checklist

• Have you read through the contributor guidelines?
• Have you signed the Lightbend CLA?
• Have you squashed your commits?
• Have you added copyright headers to new files?
• Have you updated the documentation?
• Have you added tests for any changed functionality?

Purpose

Easier/safer pattern matching on JsError:

import play.api.libs.json.JsError

def msg(err: JsError): Option[String] = err match {
  case JsError.Message(msg) => Some(msg)
  case _ => None
}

def cause(err: JsError): Option[(String, Exception)] = err match {
  case JsError.Detailed(msg, ex: Exception) => Some(msg -> ex)
  case _ => None
}

[ennru]

Close/open to get Travis started on this.

[cchantep]

Close/open to get Travis started on this.

Travis really doesn't seem stable these days ...

[ennru]

Nice!
LGTM.

[cchantep]

Thx @ennru