Add Symfony 8 and Behat 4 support

[shahinataei-ts]

Summary

This PR adds support for Symfony 8 and Behat 4.

The extension code already has the required return types on process() methods, making it compatible with both Behat 3.x and 4.x interfaces (as noted by @mpdude in #218).

Changes

• Update behat/behat constraint to ^3.22 || ^4.0
• Update symfony/* dependencies to include ^8.0
• Add CI matrix entry for Symfony 8.0 with Behat 4.x-dev

Notes

• Symfony 8 requires Behat 4.x-dev as Behat 3.x doesn't declare Symfony 8 compatibility
• This PR builds on the discussion in Add Symfony 8 support #218, incorporating @mpdude's insight that the extension is already code-compatible

Related

• [4.x] feat: Add Symfony 8 support Behat/Behat#1687 (Symfony 8 support merged into Behat 4.x)
• Add Symfony 8 support #218 (Previous Symfony 8 support PR, still in draft)

[mpdude]

Careful: There is no Behat 4 (yet), so you cannot truly know what the API might look like or how it might change. So maybe it's too early to declare compatibility.

[shahinataei-ts]

Careful: There is no Behat 4 (yet), so you cannot truly know what the API might look like or how it might change. So maybe it's too early to declare compatibility.

Thanks @mpdude, fair point.

You're right that Behat 4 isn't released yet. However, we're blocked on Symfony 8 since Behat 3.x doesn't support it, and the extension only uses core Behat interfaces that are unlikely to change before release.

If you prefer a more conservative approach, I'm happy to:

• Keep ^3.22 only and just add CI testing for 4.x-dev
• Or use ^3.22 || 4.0.x-dev to be explicit about the dev constraint

What works best for this project?

[aso824]

You need also to add extension in configuration:

new Profile('default')
    ->withExtension(
        new class implements \Behat\Config\ExtensionConfigInterface {
            public function name(): string
            {
                return \FriendsOfBehat\SymfonyExtension\ServiceContainer\SymfonyExtension::class;
            }

            public function toArray(): array
            {
                return ['bootstrap' => 'tests/bootstrap.php'];
            }
        }
    )

Also, Behat 4.0 won't support YAML configuration, so Flex fixtures will need to be adjusted later.

[bytes-max]

Symfony 8 is out for quite some time, and we'd love to see this PR getting pushed forward. Is there any chance it can get prioritized, so that we can continue working with Behat? We have built nearly thousands of features and going forward is more important than sticking to the Testing Framework, but we are used to it and would love to use it in the future just as well.