So, I was trying out typescript, in the mongoose website i could see guide for typescript, to analyize the code, I copied a snippet from the official documentation.

import { Document, Model, Query, Schema, connect, model } from 'mongoose';

interface Project {
  name: string;
  stars: number;
}

const schema = new Schema<Project>({
  name: { type: String, required: true },
  stars: { type: Number, required: true }
});
// Query helpers should return `Query<any, Document<DocType>> & ProjectQueryHelpers`
// to enable chaining.
interface ProjectQueryHelpers {
  byName(name: string): Query<any, Document<Project>> & ProjectQueryHelpers;
}

// The error is on the below line, it says Property 'byName' does not exist on type '{}'

schema.query.byName = function(name): Query<any, Document<Project>> & ProjectQueryHelpers {
  return this.find({ name: name });
};

// 2nd param to `model()` is the Model class to return.
const ProjectModel = model<Project, Model<Project, ProjectQueryHelpers>>('Project', schema);

run().catch(err => console.log(err));

async function run(): Promise<void> {
  await connect('mongodb://localhost:27017/test');
  
  // Equivalent to `ProjectModel.find({ stars: { $gt: 1000 }, name: 'mongoose' })`
  await ProjectModel.find().where('stars').gt(1000).byName('mongoose');
}

I am not sure why this error has occured, can someone help me out? When inspecting the schema object I could see the query was { }. But why so?