Cannot deduce correct type

[loevgaard]

Example
https://psalm.dev/r/8a642de112

Explanation
Since I am checking for all relevant types before line 16, $value can only be string at this point. Psalm doesn't seem to agree.

Am I missing something?

[psalm-github-bot]

I found these snippets:

https://psalm.dev/r/8a642de112

<?php

/**
 * @return ($value is null ? null : \DateTimeImmutable)
 */
function convertDateTime(null|\DateTimeInterface|string $value): ?\DateTimeImmutable
{
    if (null === $value || $value instanceof \DateTimeImmutable) {
        return $value;
    }

    if ($value instanceof \DateTimeInterface) {
        return \DateTimeImmutable::createFromInterface($value);
    }

    $res = \DateTimeImmutable::createFromFormat(\DATE_ATOM, $value);
    if (false === $res) {
        throw new \InvalidArgumentException(sprintf('The value %s is not a valid date time string based on the format %s', $value, \DATE_ATOM));
    }

    return $res;
}

Psalm output (using commit 79ab7e2):

ERROR: PossiblyInvalidCast - 16:61 - DateTimeInterface cannot be cast to string

ERROR: PossiblyInvalidArgument - 16:61 - Argument 2 of DateTimeImmutable::createFromFormat expects string, but possibly different type TGeneratedFromParam0:fn-convertdatetime as DateTimeInterface|string provided

ERROR: PossiblyInvalidArgument - 18:124 - Argument 2 of sprintf expects float|int|object{__tostring()}|string, but possibly different type TGeneratedFromParam0:fn-convertdatetime as DateTimeInterface|string provided