MethodSignatureMismatch - Argument 1 of DateTime::__unserialize has wrong type 'mixed', expecting 'array<array-key, mixed>' as defined by DateTimeInterface::__unserialize

[michnovka]

Running on PHP 8.2, I have this code:

I cannot reproduce it on psalm.dev, but I assume it has to do with stubs.

<?php

declare(strict_types=1);

namespace App\Extension\Type;

use DateTime as PHPGlobalDateTime;

class DateTime extends PHPGlobalDateTime
{
    public function __toString(): string
    {
        return $this->format('U');
    }
}

Getting:

ERROR: MethodSignatureMismatch - src/Extension/Type/DateTime.php:10:7 - Argument 1 of DateTime::__unserialize has wrong type 'mixed', expecting 'array<array-key, mixed>' as defined by DateTimeInterface::__unserialize (see https://psalm.dev/042)
class DateTime extends PHPGlobalDateTime implements StringableDateTimeInterface

[orklah]

Can you check if it reproduces if you don't name your class DateTime ?

Also, it seems that your snippet is not complete, it seems it should implement StringableDateTimeInterface too. Can we have the code for that?

[michnovka]

@orklah the StringableDateTimeInterface is irrelevant, I didnt include it in the snippet as I was reproducing the issue without it also.

I renamed the class from DateTime and the issue persist. This is the minimum reproducible example for me on PHP 8.2 and psalm 5.4

<?php

declare(strict_types=1);

namespace App\Extension\Type;

use DateTime;

class DateTime2 extends DateTime
{
    public function __toString(): string
    {
        return $this->format('U');
    }
}

getting:

ERROR: MethodSignatureMismatch - src/Extension/Type/DateTime2.php:9:7 - Argument 1 of DateTime::__unserialize has wrong type 'mixed', expecting 'array<array-key, mixed>' as defined by DateTimeInterface::__unserialize (see https://psalm.dev/042)
class DateTime2 extends DateTime

[orklah]

Oh, great, in 8.2, both DateTime and DateTimeInterface have a __unserialize method: https://3v4l.org/RtT39#v8.2.0 contrary to what we can find in documentation: https://www.php.net/manual/en/class.datetimeinterface.php

So we're actually missing definitions for it in https://github.com/vimeo/psalm/blob/master/dictionaries/CallMap_82_delta.php

We have an article about editing those files: https://psalm.dev/docs/contributing/editing_callmaps/ Are you up for a PR? :)

[michnovka]

@orklah have a look

[KevinMarques]

I'm still experiencing this issue with PHP 8.2.7 and Psalm 5.12 (also tried master, 5.11, 5.10, 5.9...) with errorLevel 7 or lower and this example:

<?php

declare(strict_types=1);

namespace App\Extension\Type;

use DateTime;

class DateTime2 extends DateTime
{
    public function __toString(): string
    {
        return $this->format('U');
    }
}

Same error:

MethodSignatureMismatch - Argument 1 of DateTime::__unserialize has wrong type 'mixed', expecting 'array<array-key, mixed>' as defined by DateTimeInterface::__unserialize.

@orklah can you reopen this issue and have a look?

[kylekatarnls]

Sounds like it needs all DateTime, DateTimeImmutable and DateTimeInterface to be set as it's not a "real" interface.

[kylekatarnls]

The error correctly disappear with #10131 with both PHP 8.1 or 8.2 (so does not sound like the definition in CallMap_82_delta is needed.