MediaWiki  master
SearchExactMatchRescorer.php
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1 <?php
26 
45  public function rescore( $search, $namespaces, $srchres, $limit ) {
46  // Pick namespace (based on PrefixSearch::defaultSearchBackend)
47  $ns = in_array( NS_MAIN, $namespaces ) ? NS_MAIN : reset( $namespaces );
48  $t = Title::newFromText( $search, $ns );
49  if ( !$t || !$t->exists() ) {
50  // No exact match so just return the search results
51  return $srchres;
52  }
53  $string = $t->getPrefixedText();
54  $key = array_search( $string, $srchres );
55  if ( $key !== false ) {
56  // Exact match was in the results so just move it to the front
57  return $this->pullFront( $key, $srchres );
58  }
59  // Exact match not in the search results so check for some redirect handling cases
60  if ( $t->isRedirect() ) {
61  $target = $this->getRedirectTarget( $t );
62  $key = array_search( $target, $srchres );
63  if ( $key !== false ) {
64  // Exact match is a redirect to one of the returned matches so pull the
65  // returned match to the front. This might look odd but the alternative
66  // is to put the redirect in front and drop the match. The name of the
67  // found match is often more descriptive/better formed than the name of
68  // the redirect AND by definition they share a prefix. Hopefully this
69  // choice is less confusing and more helpful. But it might not be. But
70  // it is the choice we're going with for now.
71  return $this->pullFront( $key, $srchres );
72  }
73  $redirectTargetsToRedirect = $this->redirectTargetsToRedirect( $srchres );
74  if ( isset( $redirectTargetsToRedirect[$target] ) ) {
75  // The exact match and something in the results list are both redirects
76  // to the same thing! In this case we'll pull the returned match to the
77  // top following the same logic above. Again, it might not be a perfect
78  // choice but it'll do.
79  return $this->pullFront( $redirectTargetsToRedirect[$target], $srchres );
80  }
81  } else {
82  $redirectTargetsToRedirect = $this->redirectTargetsToRedirect( $srchres );
83  if ( isset( $redirectTargetsToRedirect[$string] ) ) {
84  // The exact match is the target of a redirect already in the results list so remove
85  // the redirect from the results list and push the exact match to the front
86  array_splice( $srchres, $redirectTargetsToRedirect[$string], 1 );
87  array_unshift( $srchres, $string );
88  return $srchres;
89  }
90  }
91 
92  // Exact match is totally unique from the other results so just add it to the front
93  array_unshift( $srchres, $string );
94  // And roll one off the end if the results are too long
95  if ( count( $srchres ) > $limit ) {
96  array_pop( $srchres );
97  }
98  return $srchres;
99  }
100 
106  private function redirectTargetsToRedirect( array $titles ) {
107  $result = [];
108  foreach ( $titles as $key => $titleText ) {
109  $title = Title::newFromText( $titleText );
110  if ( !$title || !$title->isRedirect() ) {
111  continue;
112  }
113  $target = $this->getRedirectTarget( $title );
114  if ( !$target ) {
115  continue;
116  }
117  $result[$target] = $key;
118  }
119  return $result;
120  }
121 
129  private function pullFront( $key, array $array ) {
130  $cut = array_splice( $array, $key, 1 );
131  array_unshift( $array, $cut[0] );
132  return $array;
133  }
134 
140  private function getRedirectTarget( $title ) {
141  $redirectStore = MediaWikiServices::getInstance()->getRedirectStore();
142  $redir = $redirectStore->getRedirectTarget( $title );
143 
144  // Needed to get the text needed for display.
145  $redir = Title::castFromLinkTarget( $redir );
146  return $redir ? $redir->getPrefixedText() : null;
147  }
148 }
const NS_MAIN
Definition: Defines.php:64
Service locator for MediaWiki core services.
Represents a title within MediaWiki.
Definition: Title.php:76
An utility class to rescore search results by looking for an exact match in the db and add the page f...
rescore( $search, $namespaces, $srchres, $limit)
Default search backend does proper prefix searching, but custom backends may sort based on other algo...