original_string: protected function collectForeignKeys()
      {
          $keys = [];
  
          foreach ($this->info->relations as $relation) {
  
              if ( ! in_array(
                  $relation->type,
                  [ RelationType::BELONGS_TO, RelationType::MORPH_TO, RelationType::BELONGS_TO_THROUGH ]
              )) {
                  continue;
              }
  
              $keys = array_merge($keys, $relation->foreign_keys);
          }
  
          return $keys;
      }
code: protected function collectForeignKeys()
      {
          $keys = [];
  
          foreach ($this->info->relations as $relation) {
  
              if ( ! in_array(
                  $relation->type,
                  [ RelationType::BELONGS_TO, RelationType::MORPH_TO, RelationType::BELONGS_TO_THROUGH ]
              )) {
                  continue;
              }
  
              $keys = array_merge($keys, $relation->foreign_keys);
          }
  
          return $keys;
      }
code_tokens: protected function collectForeignKeys ( ) { $ keys = [ ] ; foreach ( $ this -> info -> relations as $ relation ) { if ( ! in_array ( $ relation -> type , [ RelationType :: BELONGS_TO , RelationType :: MORPH_TO , RelationType :: BELONGS_TO_THROUGH ] ) ) { continue ; } $ keys = array_merge ( $ keys , $ relation -> foreign_keys ) ; } return $ keys ; }
docstring: Returns list of foreign key attribute names on this model.
  
  @return string[]
docstring_tokens: Returns list of foreign key attribute names on this model .