DataProviderManager::getSubstitutionProvider

protected function getSubstitutionProvider(string $provider): ?string
{
	foreach($this->substitutionProviders as $originalProvider => $substitutionProvider)
	{
		if(
			strtolower($provider) === strtolower($originalProvider)
			&& is_a($substitutionProvider, $provider, true)
		)
		{
			return $substitutionProvider;
		}
	}

	return null;
}