False positive with enum narrowing leading to TypeDoesNotContainType

[mkroeders]

When checking if a value is not of a specific class ie instanceof and using not equals with an enum, the enum is not added as a possible value. This leads to a TypeDoesNotContainType in valid code.

https://psalm.dev/r/1e34436864

[psalm-github-bot]

I found these snippets:

https://psalm.dev/r/1e34436864

<?php
interface Inter {
}
enum Enu implements Inter {
    case Bar;
}
class Clas implements Inter {
}

function far(Inter $fiz): string {
    if (!$fiz instanceof Clas && $fiz !== Enu::Bar) {
        throw new Exception();
    }
    
    return $fiz === Enu::Bar
        ? 'abz'
        : 'zba';
}

Psalm output (using commit 3af9ccd):

ERROR: TypeDoesNotContainType - 15:12 - enum(Enu::Bar) cannot be identical to Clas

ERROR: TypeDoesNotContainType - 15:12 - Type Clas for $fiz is never =enum(Enu::Bar)

[weirdan]

We should probably start with a simpler https://psalm.dev/r/fb4c624cea.

[psalm-github-bot]

I found these snippets:

https://psalm.dev/r/fb4c624cea

<?php

interface Inter {}

enum Enu implements Inter {
    case Bar;
}

function far(Inter $fiz): void { 
    if ($fiz === Enu::Bar) {}
    throw new RuntimeException;
}

Psalm output (using commit 3af9ccd):

ERROR: TypeDoesNotContainType - 10:9 - Type Inter for $fiz is never =enum(Enu::Bar)