MediaWiki  master
SearchExactMatchRescorer.php
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1 <?php
25 
44  public function rescore( $search, $namespaces, $srchres, $limit ) {
45  // Pick namespace (based on PrefixSearch::defaultSearchBackend)
46  $ns = in_array( NS_MAIN, $namespaces ) ? NS_MAIN : reset( $namespaces );
47  $t = Title::newFromText( $search, $ns );
48  if ( !$t || !$t->exists() ) {
49  // No exact match so just return the search results
50  return $srchres;
51  }
52  $string = $t->getPrefixedText();
53  $key = array_search( $string, $srchres );
54  if ( $key !== false ) {
55  // Exact match was in the results so just move it to the front
56  return $this->pullFront( $key, $srchres );
57  }
58  // Exact match not in the search results so check for some redirect handling cases
59  if ( $t->isRedirect() ) {
60  $target = $this->getRedirectTarget( $t );
61  $key = array_search( $target, $srchres );
62  if ( $key !== false ) {
63  // Exact match is a redirect to one of the returned matches so pull the
64  // returned match to the front. This might look odd but the alternative
65  // is to put the redirect in front and drop the match. The name of the
66  // found match is often more descriptive/better formed than the name of
67  // the redirect AND by definition they share a prefix. Hopefully this
68  // choice is less confusing and more helpful. But it might not be. But
69  // it is the choice we're going with for now.
70  return $this->pullFront( $key, $srchres );
71  }
72  $redirectTargetsToRedirect = $this->redirectTargetsToRedirect( $srchres );
73  if ( isset( $redirectTargetsToRedirect[$target] ) ) {
74  // The exact match and something in the results list are both redirects
75  // to the same thing! In this case we'll pull the returned match to the
76  // top following the same logic above. Again, it might not be a perfect
77  // choice but it'll do.
78  return $this->pullFront( $redirectTargetsToRedirect[$target], $srchres );
79  }
80  } else {
81  $redirectTargetsToRedirect = $this->redirectTargetsToRedirect( $srchres );
82  if ( isset( $redirectTargetsToRedirect[$string] ) ) {
83  // The exact match is the target of a redirect already in the results list so remove
84  // the redirect from the results list and push the exact match to the front
85  array_splice( $srchres, $redirectTargetsToRedirect[$string], 1 );
86  array_unshift( $srchres, $string );
87  return $srchres;
88  }
89  }
90 
91  // Exact match is totally unique from the other results so just add it to the front
92  array_unshift( $srchres, $string );
93  // And roll one off the end if the results are too long
94  if ( count( $srchres ) > $limit ) {
95  array_pop( $srchres );
96  }
97  return $srchres;
98  }
99 
105  private function redirectTargetsToRedirect( array $titles ) {
106  $result = [];
107  foreach ( $titles as $key => $titleText ) {
108  $title = Title::newFromText( $titleText );
109  if ( !$title || !$title->isRedirect() ) {
110  continue;
111  }
112  $target = $this->getRedirectTarget( $title );
113  if ( !$target ) {
114  continue;
115  }
116  $result[$target] = $key;
117  }
118  return $result;
119  }
120 
128  private function pullFront( $key, array $array ) {
129  $cut = array_splice( $array, $key, 1 );
130  array_unshift( $array, $cut[0] );
131  return $array;
132  }
133 
139  private function getRedirectTarget( $title ) {
140  $redirectStore = MediaWikiServices::getInstance()->getRedirectStore();
141  $redir = $redirectStore->getRedirectTarget( $title );
142 
143  // Needed to get the text needed for display.
144  $redir = Title::castFromLinkTarget( $redir );
145  return $redir ? $redir->getPrefixedText() : null;
146  }
147 }
const NS_MAIN
Definition: Defines.php:64
MediaWikiServices is the service locator for the application scope of MediaWiki.
An utility class to rescore search results by looking for an exact match in the db and add the page f...
getRedirectTarget( $title)
Get a redirect's destination from a title.
rescore( $search, $namespaces, $srchres, $limit)
Default search backend does proper prefix searching, but custom backends may sort based on other algo...
pullFront( $key, array $array)
Returns an array where the element of $array at index $key becomes the first element.
static castFromLinkTarget( $linkTarget)
Same as newFromLinkTarget, but if passed null, returns null.
Definition: Title.php:306
static newFromText( $text, $defaultNamespace=NS_MAIN)
Create a new Title from text, such as what one would find in a link.
Definition: Title.php:370