Strange behavior when assigning to list and class-string-map

[ptomulik]

False negative for list and false positive for class-string-map. I think these two problems are related:

https://psalm.dev/r/1abd6b7b03

I guess, also #4460 is related.

[psalm-github-bot]

I found these snippets:

https://psalm.dev/r/1abd6b7b03

<?php

final class ListTest
{
    /** @var list */
    private array $list = [];
    
    public function set1(int $i, mixed $v): void {
        $this->list[$i] = $v; // OK, it's an error
    }
    
    public function set2(int $i, mixed $v): void {
        if (isset($this->list[$i])){} // no-op
        $this->list[$i] = $v; // WRONG, it should still be an error
    }
}

final class ClassMapTest
{
    /** @var class-string-map<T,T> */
    private array $map = [];
    
    /**
     * @template U of object
     * @param class-string<U> $k
     * @param U $v
     */
    public function set1(string $k, object $v): void {
        $this->map[$k] = $v; // false positive
    }
    
    /**
     * @template U of object
     * @param class-string<U> $k
     * @param U $v
     */
    public function set2(string $k, object $v): void {
        if (isset($this->map[$k])){} // no-op
        $this->map[$k] = $v; // somehow the false positive is silenced
    }
}

Psalm output (using commit 8f98539):

ERROR: PropertyTypeCoercion - 9:9 - $this->list expects 'list<mixed>',  parent type 'non-empty-array<int, mixed>' provided

ERROR: InvalidPropertyAssignmentValue - 29:9 - $this->map with declared type 'class-string-map<T as object, T:class-string-map as object>' cannot be assigned type 'non-empty-array<(class-string<T:class-string-map as object>)|(class-string<U:fn-classmaptest::set1 as object>), (T:class-string-map as object)|(U:fn-classmaptest::set1 as object)>'

[ptomulik]

The false-positive ERROR: InvalidPropertyAssignmentValue - 29:9 gone (fixed in #9415). The bug that alters ListTest has still to be fixed.

[orklah]

Seems fixed :)