Ambigious comparing primitive with object

[sirian]

🐛 Bug Report

Primitive values compare with objects is ambigious

const Bool = Boolean;
const classes = [
    Boolean,
    class Boolean extends Bool {},
    class Boolean2 extends Bool {},
    class Boolean {
        static [Symbol.hasInstance](ctor) {return Boolean === ctor;}
        valueOf() {return false;}
        [Symbol.toPrimitive]() {return false;}
    },
];

test.each(classes)("%O", (ctor) => {
    const expected = new ctor(false);
    expected.x = 1;

    expect(false).toEqual(expected);
    expect(false).toStrictEqual(expected);
});

Look at example. there are 4 test cases

1. Boolean - native Boolean constructor
2. Boolean extending native Boolean
3. Boolean2 extending native Boolean
4. fake class Boolean

At all iterations true compared with some object (more over - I explicitly set expected.x = 1)

Results

✓ Boolean
✓ [class Boolean extends Bool]
✕ [class Boolean2 extends Bool] fails on toStrictEqual - Comparing two different types of values. Expected object but received boolean.
✕ [fake class Boolean] fails on toEqual - Comparing two different types of values. Expected object but received boolean.

Expected behavior

All of these test should fall because true not equal object with x = 1 (at least toStrictEqual)

[sirian]

Another great example:

test("", () => {
    const obj = new Boolean(false);
    const proxy = new Proxy(obj, {});

    expect(false).toEqual(obj); // pass 
    expect(false).toStrictEqual(obj); // pass
    expect(false).toEqual(proxy); // fail
    expect(false).toStrictEqual(proxy); // fail
});

[SimenB]

expect(false).toEqual(new Boolean(false)); makes sense, I think, false === Boolean(false) // true

not sure if this is a bug or expected behaviour? @thymikee @rickhanlonii thoughts?

[thymikee]

Also not sure, I'd need to check the spec to see if all this makes sense 🤷‍♂️

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[github-actions]

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