Schema Function Not Working with @key

Describe the bug

The schema function doesn’t appear to work when field is '@key'. Here’s the rule I’m trying to create:

  response-code-type:
    message: Response codes must be strings
    recommended: true
    given: $.paths.*.*.responses
    then:
      field: '@key'
      function: schema
      functionOptions:
        schema:
          type: string

To Reproduce

Given this OpenAPI document

openapi: 3.0.2
info:
  title: Test Spec
  version: 0.0.0
paths:
  /foo:
    get:
      operationId: get-foo
      responses:
        200:
          description: ''

Run this CLI command

spectral lint test-spec.yaml -r my-rules.yaml

Expected behavior

The lint output should contain the following:

 9:17  warning  response-code-type    Response codes must be strings

It might be worth noting that if the rule is changed so that type is number or integer, the rule is triggered.

Environment

• Library version: 4.2.0
• OS: Windows 10

[P0lip]

@dillonredding This one will be addressed as well, but in a slightly different manner. Spectral will warn you about property keys that are not JSON compliant (are no strings in other words). I hope that will do the trick for you.

[P0lip]

@dillonredding no rule will be needed. Each property key that could not be used in JSON will be reported automatically by Spectral