function setupTestEvent(signature) {
    wtf.trace.EventType.nextEventWireId_ = 1;

    var parsedSignature = wtf.data.Variable.parseSignature(signature);
    var name = parsedSignature.name;
    var args = parsedSignature.args;
    var writeType = new wtf.trace.EventType(
        name + '_write', wtf.data.EventClass.INSTANCE, 0, args);
    var readType = new wtf.db.EventType(
        name + '_read', wtf.data.EventClass.INSTANCE, 0, args);
    return {
      name: name,
      args: args,
      writeType: writeType,
      readType: readType,
      write: writeBuilder.generate(ctx, writeType),
      read: readBuilder.generate(readType)
    };
  }
Round-trip testing for event buffers.