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         }
  26
  27         /**
  28          * Check if flag is set.
  29          * @param int $flag
  30          * @return int 0 if unset, !=0 if set
  31          */
  32         public function checkFlag( $flag ) {
  33                 return 0;
  34         }
  35
  36         /**
  37          * Merge two field definitions if possible.
  38          *
  39          * @param SearchIndexField $that
  40          * @return SearchIndexField|false New definition or false if not mergeable.
  41          */
  42         public function merge( SearchIndexField $that ) {
  43                 return $that;
  44         }
  45
  46         /**
  47          * @inheritDoc
  48          */
  49         public function getEngineHints( SearchEngine $engine ) {
  50                 return [];
  51         }
  52 }