bug: Not inferring Native error

[Himadu2000]

What is the current behavior?
error TS7006: Parameter 'error' implicitly has an 'any' type.

steps to reproduce.
Repo to recreate
Run yarn compile

Following action

Quick code
Cat.find({}, (error) => { if (error) { return error; } });
compile with tsc --strict

What is the expected behavior?
Should infer NativeError in error

What are the versions of Node.js, Mongoose and MongoDB you are using? Note that "latest" is not a version.
Node: v14.17.0
"mongoose": "^5.12.13"

[Himadu2000]

I just noticed that mongoose is written .js not in .ts, this is one of major reasons I think I have to file an issue like mine, may I know when this library being written in typescript?

[IslandRhythms]

It already has a typescript support
https://mongoosejs.com/docs/typescript.html

[IslandRhythms]

import * as mongoose from "mongoose";

interface User{
    name: string;
}

const schema = new mongoose.Schema<User>({name: String});

mongoose.connect("mongodb://localhost:27017/test", {
  useNewUrlParser: true,
  useUnifiedTopology: true,
});

const Cat = mongoose.model("Cat", schema);

const kitty = new Cat({ name: "Zildjian" });
kitty.save().then(() => console.log("meow"));

Cat.find({}, (error) => {
  if (error) {
    return error;
  }
});

[Himadu2000]

I only see types to model only after using any method such as find, update, findbyid non of definitions get shown in the callback. Also doesn't it easy to have automatic type definitions (.d.ts) files generated from typescript and bundler rather than keeping specific.d.ts files because that costs no?

[vkarpov15]

@Himadu2000 below code compiles without error, please modify the below script to demonstrate your issue.

import * as mongoose from "mongoose";

mongoose.connect("mongodb://localhost:27017/test", {
  useNewUrlParser: true,
  useUnifiedTopology: true,
});

const Cat = mongoose.model("Cat", new mongoose.Schema({ name: String }));

const kitty = new Cat({ name: "Zildjian" });
kitty.save().then(() => console.log("meow"));

Cat.find({}, (error) => {
  if (error) {
    return error;
  }
});

[Himadu2000]

@vkarpov15 Okay, here's a example line where problem lies , in the line callback?: (err: any, the err is type of any, so it needs to be either string or different type which I am not sure what return.

[Himadu2000]

So @vkarpov15, what does err returns, I never got err but it needs to known to handle them, I can't take chances for unhandled errors on production app.