Support for Array parameters in SQL filters

[beberlei]

Supersedes #5571 by @mnogales

Fixes #2624

The original PR had a conceptual problem by putting the array detection directly into getParameter(), but this could be a BC break for array DBAL types and it could be a risk, because the generated SQL must be written by the filter implementor, so magically returning a quoted list instead a quoted value could break things.

Instead you must combine your generated SQL IN query with $this->getParameterList($name):

class CMSCountryFilter extends SQLFilter
{
    public function addFilterConstraint(ClassMetadata $targetEntity, $targetTableAlias)
    {
        if ($targetEntity->name !== CmsAddress::class || !$this->hasParameter('country')) {
            return "";
        }

        return $targetTableAlias.'.country IN (' . $this->getParameterList('country') . ')';
    }
}

To use getParameterList you must also pass the values using the new setParameterList method. It does not support type inference as we don't need to inspect the array elements then (which could be different).

$em->getFilters()->getFilter('country')->setParameter('country', ['de', 'es']);

Passing a list/single value and retrieving a single/list value (mixed up) will throw a new FilterException.

[SenseException]

Please also cover the two exception cases in getParameterList().

[SenseException]

// WARNING: no Traversable support

Still, the variable is named $isTraversable :-D.

[beberlei]

Removed traversable support explicitly now.

[SenseException]

Why changing an existing test and filter?

[beberlei]

Because we have two filters in the test, one for locale one for country. By changing one to be a list we maximize test coverage without adding more tests.

[SenseException]

After the typos that @greg0ire mentioned are fixed, this is 👍