PHP Unit Class "PHPUnit\Metadata\Api\DataProvider" not found [with repro case]

I've installed php unit via composer and have written a simple unit test file (it is actually from phpunit's example)

<?php declare(strict_types=1);

use PHPUnit\Framework\TestCase;

final class CheckFreeSeatsTest extends TestCase
{
    public function testCanBeCreatedFromValidEmail(): void
    {
        $this->assertSame("foo", "foo");   
    }
}

Nothing to write home about

Each time I execute the test file I get a

An error occurred inside PHPUnit.

Message:  Class "PHPUnit\Metadata\Api\DataProvider" not found
Location: C:\www\vendor\phpunit\phpunit\src\Framework\TestBuilder.php:38

#0 C:\www\vendor\phpunit\phpunit\src\Framework\TestSuite.php(477): PHPUnit\Framework\TestBuilder->build(Object(ReflectionClass), 'testCanBeCreate...')

I've already executed composer update, composer dumpautoload --dev, passing --bootstrap=vendor/autoload.php etc.

For whatever reason, the autoload.php (autoload_static.php to be precisely) is missing a mapping for PHPUnit\Metadata\Api\DataProvider (or even more of those)

Can somebody check, whether his or her autoload files contain "DataProvider.php" ?

For instance these are the only Metadata includes found in any autoload_*.php files

'PHPUnit\\Metadata\\UsesFunction' => __DIR__ . '/..' . '/phpunit/phpunit/src/Metadata/UsesFunction.php',
'PHPUnit\\Metadata\\Version\\ComparisonRequirement' => __DIR__ . '/..' . '/phpunit/phpunit/src/Metadata/Version/ComparisonRequirement.php',
'PHPUnit\\Metadata\\Version\\ConstraintRequirement' => __DIR__ . '/..' . '/phpunit/phpunit/src/Metadata/Version/ConstraintRequirement.php',
'PHPUnit\\Metadata\\Version\\Requirement' => __DIR__ . '/..' . '/phpunit/phpunit/src/Metadata/Version/Requirement.php',

More info: I do not use DataProvider by myself, the TestBuilder.php is creating one but it relies on autoloaded data, that seems to not being created.

Any hints on this would be great.

Repro case

Here is windows powershell repro case for a docker linux container setup that fully replicates the issue. Just put it into an empty dir and execute it.

Set-StrictMode -Version 3

$outDir = "$PSScriptRoot/out_dir"

if(Test-Path $outDir)
{
    Remove-Item -Force -Recurse $outDir | Out-Null
}

New-Item -ItemType Directory $outDir | Out-Null

@'
{
    "name": "root/app",
    "require-dev": {
        "phpunit/phpunit": "^10"
    }
}
'@ | Out-File $outDir\composer.json -Encoding ascii

docker run --volume "$($outDir):/app" --rm -it composer/composer composer update


@'
<?php declare(strict_types=1);
use PHPUnit\Framework\TestCase;

final class EmailTest extends TestCase
{
    public function testCanBeCreatedFromValidEmail(): void
    {
        $this->assertSame("foo", "foo");
    }   
}
'@ | Out-File $outDir\EmailTest.php -Encoding ascii

docker run --volume "$($outDir):/app" --rm -it composer/composer ./vendor/bin/phpunit EmailTest.php

I had the same issue recently with laravel 10, but i fixed it by downgrading the "phpunit" version to "10.0.1".

I logged this as an issue for phpunit on github.

It was closed as not an issue, but the comments in the thread are worth reading and provide alternative solutions to downgrading
https://github.com/sebastianbergmann/phpunit/issues/5477

a) Use classmap-based autoloading
b) Add psr-4 classloading work-arounds

"autoload-dev": {
        "psr-4": {
            "PHPUnit\\Metadata\\": "vendor/phpunit/phpunit/src/Metadata",
            "PHPUnit\\Metadata\\Annotation\\Parser\\": "vendor/phpunit/phpunit/src/Metadata/Parser/Annotation"
        }
    }