Proposal: Inherit constructor and static methods from base Message class

I was wondering why we are generating static methods instead of simply inheriting them from the base class. Is there a reason for that?

With these messages also also used in the frontend as part of e.g. connect-web, I think we have to be extra careful not to add too much weight especially for projects with a lot of messages.

I was thinking of doing something like this with the base Message class:

export class Message<T extends Message<T> = AnyMessage> {
  static readonly runtime: ProtoRuntime;
  static readonly typeName: string;
  static readonly fields: FieldList;

  static fromBinary<T extends Message<T>>(
    this: MessageType<T>,
    bytes: Uint8Array,
    options?: Partial<BinaryReadOptions>
  ): T {
    return new this().fromBinary(bytes, options);
  }

  static fromJson<T extends Message<T>>(
    this: MessageType<T>,
    jsonValue: JsonValue,
    options?: Partial<JsonReadOptions>
  ): T {
    return new this().fromJson(jsonValue, options);
  }

  static fromJsonString<T extends Message<T>>(
    this: MessageType<T>,
    jsonString: string,
    options?: Partial<JsonReadOptions>
  ): T {
    return new this().fromJsonString(jsonString, options);
  }

  static equals<T extends Message<T>>(
    this: MessageType<T>,
    a: T | PlainMessage<T> | undefined | null,
    b: T | PlainMessage<T> | undefined | null
  ): boolean {
    return this.runtime.util.equals(this, a, b);
  }

  constructor(data?: PartialMessage<T>) {
    const self = <typeof Message<T>>this.constructor;
    self.runtime.util.initPartial(data, this as any);
  }

  // ...
}

Are there any reasons why this wouldn’t work at runtime?

[smaye81]

Sorry for the delay. I don’t actually remember what it was either. If you are able to get around it though, as @timostamm said, we’d be all ears!

[fubhy]

@timostamm Do you think it would make sense for me to try and experiment with this a bit? Does @smaye81 maybe remember what the limitation was or one of your colleagues? I’d be keen to give it a shot unless you can confirm it’s indeed proven to be a dead-end 😃