Splat in constant array expression produces wrong array shape

[weirdan]

https://psalm.dev/r/fb451afec9

Expected: flat list (https://3v4l.org/0IdDo)

[psalm-github-bot]

I found these snippets:

https://psalm.dev/r/fb451afec9

<?php

final class Token
{
    public const ONE = [
        16 => 16,
        21 => 21,
    ];

    public const TWO = [
        17 => 17,
        22 => 22,
    ];

    public const THREE = [
        18 => 18,
        23 => 23,
    ];

    public const RESULT = [...self::ONE, ...self::TWO, ...self::THREE];
}
$_t = Token::RESULT;
/** @psalm-trace $_t */;

Psalm output (using commit 3fb9e1c):

INFO: Trace - 23:24 - $_t: array{array{16: 16, 21: 21}, array{17: 17, 22: 22}, array{18: 18, 23: 23}}

[orklah]

I took a quick glance at it. The issue is in here:

psalm/src/Psalm/Internal/PhpVisitor/Reflector/ClassLikeNodeScanner.php

Line 1167 in c2ba1fe

$const_type = SimpleTypeInferer::infer(

We loop over the class constants and we use SimpleTypeInferer::infer to calculate the type. Unfortunately, this method doesn't handle unpacking at all. We should probably take a look at how it's handled in ArrayAnalyzer::handleUnpackedArray and reuse code somehow

[weirdan]

@ondrejmirtes PHPStan also suffers from this bug: https://phpstan.org/r/9d00884a-5311-45c1-ad35-f2d7cdcbb852

[orklah]

@weirdan FYI you can dump types in PHPStan, similar to @psalm-trace: https://phpstan.org/r/4b4198b8-b52a-4c72-b185-42b3b5c8dc94

[ondrejmirtes]

Please open a bug report in PHPStan's repo, thanks :)