Using spread operator on observable object remove some properties (function)

[pinonpierre]

Intended outcome:

Retrieve the object with all its properties when using the spread operator on a mobx observable

Actual outcome:

Retrieve the object without function properties when using the spread operator on a mobx observable

How to reproduce the issue:

export class TestStore {
    constructor() {
        makeObservable(this);
    }

    @observable
    test?: object;

    @action
    setTest(test: object) {
        this.test = test;
    }
}

In my React Component

    const myObject = {a: "a", b: "b", c: () => console.log("ok")};
    console.log("simple var:", {...myObject});

    testStore.setTest(myObject);
    console.log("mobx observable:", {...testStore.test});

Console output:

    simple var: {a: "a", b: "b", c: ƒ}
    mobx observable: {a: "a", b: "b"}

Versions

Doesn't work on the last version:

"mobx": "^6.0.4",
"mobx-react-lite": "^3.1.6",
"mobx-utils": "^6.0.1",

Works on the previous version:

"mobx": "^5.15.4",
"mobx-react-lite": "^2.0.7",
"mobx-utils": "^5.6.1",

Thanks

[danielkcz]

Please provide runnable reproduction.

[pinonpierre]

https://codesandbox.io/s/mobxbug-949dd

[urugator]

Duplicate of #2629 and #2586