Error serialization logic is faulty

[rekmarks]

Errors are "serialized" using the serializeError function, and this function has considerable issues. We use the internal utility isValidCode which only returns true if this package has a message for that code in its enums. This sucks, because technically any valid integer code is valid. I don't know what I was thinking when I implemented this.

The error serialization should continue to optionally include the stack property, but it should permit any error object (and especially, error code) that is valid per the JSON-RPC 2.0 specification, i.e. any integer number. Only if the original error object does not conform to the following interface should we modify it and replace it with a -32603 error:

type JsonRpcError = {
  code: number, // specifically, any safe integer
  message: string,
  data?: Json,
  stack?: string, // non-standard, but on occasion useful
}

If a value passed to serializeError violates this interface in any way, we should create a new JSON-RPC error as follows, where data.originalError is the original error value if it's valid JSON:

{
  code: -32603,
  message: 'Invalid internal error. See "data.originalError" for original value. Please report this bug.',
  data: { originalError }
}

See #48 and the following screenshot for examples of how the current logic mangles errors:

[kumavis]

need to rewrite enumerable to true

> e = new Error
Error
    at REPL1:1:5
    at Script.runInThisContext (node:vm:129:12)
    at REPLServer.defaultEval (node:repl:566:29)
    at bound (node:domain:421:15)
    at REPLServer.runBound [as eval] (node:domain:432:12)
    at REPLServer.onLine (node:repl:893:10)
    at REPLServer.emit (node:events:539:35)
    at REPLServer.emit (node:domain:475:12)
    at REPLServer.Interface._onLine (node:readline:487:10)
    at REPLServer.Interface._line (node:readline:864:8)
> JSON.stringify(e)
'{}'
> Object.getOwnPropertyDescriptors(e)
{
  stack: {
    value: 'Error\n' +
      '    at REPL1:1:5\n' +
      '    at Script.runInThisContext (node:vm:129:12)\n' +
      '    at REPLServer.defaultEval (node:repl:566:29)\n' +
      '    at bound (node:domain:421:15)\n' +
      '    at REPLServer.runBound [as eval] (node:domain:432:12)\n' +
      '    at REPLServer.onLine (node:repl:893:10)\n' +
      '    at REPLServer.emit (node:events:539:35)\n' +
      '    at REPLServer.emit (node:domain:475:12)\n' +
      '    at REPLServer.Interface._onLine (node:readline:487:10)\n' +
      '    at REPLServer.Interface._line (node:readline:864:8)',
    writable: true,
    enumerable: false,
    configurable: true
  }
}
> Reflect.defineProperty(e, 'stack', { enumerable: true })
true
> JSON.stringify(e)
'{"stack":"Error\\n    at REPL1:1:5\\n    at Script.runInThisContext (node:vm:129:12)\\n    at REPLServer.defaultEval (node:repl:566:29)\\n    at bound (node:domain:421:15)\\n    at REPLServer.runBound [as eval] (node:domain:432:12)\\n    at REPLServer.onLine (node:repl:893:10)\\n    at REPLServer.emit (node:events:539:35)\\n    at REPLServer.emit (node:domain:475:12)\\n    at REPLServer.Interface._onLine (node:readline:487:10)\\n    at REPLServer.Interface._line (node:readline:864:8)"}'
>