State typing doesn't work with classes with private attributes/methods

[hugoattal]

Reproduction

Here is a little example

import { defineStore } from "pinia";

// This is a class called "Thing" with a private attribute name
class Thing {
    private readonly name: string;

    constructor(name: string) {
        this.name = name;
    }

    getName(): string {
        return this.name;
    }
}

// This function expects a Thing as argument
function displayName(thing: Thing) {
    console.log(thing.getName());
}

// This little example works as intended
const a: Thing = new Thing("test");
displayName(a);

export const useTestStore = defineStore({
    id: `test`,
    actions: {
        getThingName() {
            // Error TS2345
            displayName(this.thing);
        }
    },
    state: () => ({
        thing: new Thing("test")
    })
});

Steps to reproduce the behavior

Just paste this code in WebStorm (last version)

Expected behavior

It should pass typescript compilation

Actual behavior

Typescript fire a TS2345 error because property "name" is missing

Additional information

It can be "fixed" this by forcing the type:

Also, it's rather a small bug, I just wanted to mention it if anyone encountered this. I ❤️ 🍍 !

[posva]

Duplicate of vuejs/core#2981

[posva]

Pinia unwraps any property passed in the state and the resulting type is also unwrapped with UnwrapRef. For the moment, you need to manually cast it:

      displayName(this.thing as Thing)