Rule Request: Switch Case RawValue

New Issue Checklist

• Updated SwiftLint to the latest version
• I searched for existing GitHub issues

New rule request

Switch case rawValue

1. Trigger a warning if using myEnum.rawValue to evaluate switch cases. This style forces the use of a default. Good practice could be to convert the switched value to the enum (perhaps with guard) prior to setting it as the switch parameter.

2. Triggers
   Trigger example:

    func myFunc(myParam: String) {
      switch myParam {
      case myEnum.opt1.rawValue:
        // do something
      case myEnum.opt2.rawValue :  
        // do something else
      default:
        break // needed since myParam could be anything
      }
    }

note: spacing after rawValue extra space should still trigger the warning

Not triggered if .rawValue isn't used

3. Only severity should be configurable

4. Rule should be Opt-in since there may be some reason the code requires a switch on rawValue

Start by locating SwiftLint's existing opt-in rule implementations and their tests, then compare their configuration and severity handling with the requested behavior. The work is done when switches matching the rawValue examples warn, non-rawValue cases do not, spacing does not prevent detection, severity is configurable, and the rule remains opt-in.