[Validator] Fix using known option names as field names

[HypeMC]

Q	A
Branch?	5.4
Bug fix?	yes
New feature?	no
Deprecations?	no
Issues	Fix #52993
License	MIT

Instead of assuming $fields is not the fields array when any of the keys is a known option, let's assume it is the fields array if all keys are known options. Of course, this approach won't work if someone names all their fields after known options, but I don't believe that will actually happen.

[nicolas-grekas]

Suggested change

	$knowOptions = array_map(function (\ReflectionParameter $parameter) {
	return $parameter->name;
	}, (new \ReflectionMethod(__METHOD__))->getParameters());
	static $knowOptions;
	$knownOptions ??= array_column((new \ReflectionMethod(__METHOD__))->getParameters(), 'name');

[HypeMC]

Done, I had to adjust the code for PHP 7.2. I'm wondering, is the static variable necessary since this all happens in the constructor?

[fabpot]

Thank you @HypeMC.

[tscni]

Fyi, this breaks code where $fields is an empty array

[xabbuh]

@tscni Can you please try #53383?

[dresslerdemos]

I tried this (#53383) fix and it still breaks for an empty list of constraints, which I confirmed was working in v5.4.29:

    public function testEmptyConstraintList()
    {
        // Symfony\Component\Validator\Exception\InvalidOptionsException : The options "foo" do not exist in constraint "Symfony\Component\Validator\Constraints\Collection".
        new Collection(
            [
                'foo' => []
            ],
            null,
            null,
            true,
            false
        );

        self::assertTrue(true);
    }

For my use case I can mitigate this by using fields, but I wanted to give a heads up regarding backward compatibility.

    public function testEmptyConstraintList2()
    {
        new Collection(
            ['fields' => [
                'foo' => []
            ]],
            null,
            null,
            true,
            false
        );

        self::assertTrue(true);
    }

[nerones]

just had the same problem as @dresslerdemos

[xabbuh]

I have a fix pending locally. I’ll keep you posted.

[xabbuh]

@dresslerdemos @nerones Can you check if #53443 fixes it for you?