includes/search/NullIndexField.php

   1 <?php
   2
   3 /**
   4  * Null index field - means search engine does not implement this field.
   5  */
   6 class NullIndexField implements SearchIndexField {
   7
   8         /**
   9          * Get mapping for specific search engine
  10          * @param SearchEngine $engine
  11          * @return array|null Null means this field does not map to anything
  12          */
  13         public function getMapping( SearchEngine $engine ) {
  14                 return null;
  15         }
  16
  17         /**
  18          * Set global flag for this field.
  19          *
  20          * @param int $flag Bit flag to set/unset
  21          * @param bool $unset True if flag should be unset, false by default
  22          * @return $this
  23          */
  24         public function setFlag( $flag, $unset = false ) {
  25                 return $this;
  26         }
  27
  28         /**
  29          * Check if flag is set.
  30          * @param int $flag
  31          * @return int 0 if unset, !=0 if set
  32          */
  33         public function checkFlag( $flag ) {
  34                 return 0;
  35         }
  36
  37         /**
  38          * Merge two field definitions if possible.
  39          *
  40          * @param SearchIndexField $that
  41          * @return SearchIndexField|false New definition or false if not mergeable.
  42          */
  43         public function merge( SearchIndexField $that ) {
  44                 return $that;
  45         }
  46
  47         /**
  48          * @inheritDoc
  49          */
  50         public function getEngineHints( SearchEngine $engine ) {
  51                 return [];
  52         }
  53 }