logicalAnd() public method

It also accepts a single array of constraints to be concatenated.
public logicalAnd ( mixed $constraint1 ) : object
$constraint1 mixed The first of multiple constraints or an array of constraints.
return object
 /**
  * @param Query $query
  * @param AssetCollection $assetCollection
  * @return void
  */
 protected function addAssetCollectionToQueryConstraints(Query $query, AssetCollection $assetCollection = null)
 {
     if ($assetCollection === null) {
         return;
     }
     $constraints = $query->getConstraint();
     $query->matching($query->logicalAnd($constraints, $query->contains('assetCollections', $assetCollection)));
 }