fix(utilities): exclude id properties from arrays

[thompsonsj]

• Prevent fields with a name of id from identifying as a localized field.
• Exclude arrays of empty objects from fields.json.

Details

getLocalizedFields supports top-level localized: true settings on fields that contain a group of fields. This support was added in #20.

Payload CMS adds text fields for the id in some cases: e.g. each item in an array will have it's own id. Here's an example doc with values in an array field:

{
  "id": "649da59a7a48bc576d04966f",
  "arrayField": [
    {
      "content": [
        {
          "children": [
            {
              "text": "Test content 1"
            }
          ]
        }
      ],
      "metaDescription": "Test meta description 1"
    },
    {
      "content": [
        {
          "children": [
            {
              "text": "Test content 2"
            }
          ]
        }
      ],
      "metaDescription": "Test meta description 2"
    }
  ],
  "createdAt": "2023-06-29T15:39:06.628Z",
  "updatedAt": "2023-07-03T10:32:43.988Z"
}

In this scenario, fields.json can end up containing id fields. In the above example, each array item only contains a richText field - which get sent to html files instead of fields.json.

{
  "arrayField": [
    {
      "id": "649cd20ebac7445191be36b0"
    },
    {
      "id": "649cd219bac7445191be36b1"
    }
  ]
}

Note that integration tests are written to test against this scenario. Providing fixtures to the unit tests in the utilities folder won't work because this situation only arises when a Payload CMS installation adds fields.