Inconsistent syntax for property paths in error objects

[Steffan-Ennis]

Prerequisites

• I have read the documentation;
• In the case of a bug report, I understand that providing a SSCCE example is tremendously useful to the maintainers.

Description

Error objects in the errors collection passed into the transformErrors callback are inconsistent

Field paths have two different syntaxes.

Property keys can delimited by . and also encapsulated by [] when special characters or white space is present

This may be intentional but it is a breaking change introduced in v1.0.0.
It would be nice to have this noted in the release notes.

Steps to Reproduce

1. Use the following schema and transformErrors

const transformErrors = errors => {
  errors.forEach(error => {
    console.log(error.property)
  })
}

const schema = {
  "type": "object",
  "properties": {
    "firstName": {
      "type": "string"
    },
    "first-name": {
      "type": "string"
    }
  },
  "required": [
    "first-name",
    "firstName"
  ]
}

3. submit the form and leave firstName and first-name emtpy

Expected behavior

-> "['firstName']"
-> "['first-name']"

Actual behavior

-> ".firstName"
-> "['first-name']"

Version

1.0.0

[epicfaace]

Playground link

I'm guessing we don't want to go with the "expected behavior", but rather just document this? i.e., error.property is equal to ajv's dataPath, which is just Javascript property accessor notation to get the value.