build trigrams

src/Indexer/TNTIndexer.php

@@ -458,6 +458,17 @@ public function buildDictionary($filename, $count = -1, $hits = true, $docs = fa
         file_put_contents($filename, $dictionary, LOCK_EX);
     }
 
+    public function buildTrigrams($keyword)
+    {
+        $t        = "__" . $keyword . "__";
+        $trigrams = "";
+        for ($i = 0; $i < strlen($t) - 2; $i++) {
+            $trigrams .= substr($t, $i, 3) . " ";
+        }
+
+        return trim($trigrams);
+    }
+
     public function info($text)
     {
         if (!$this->disableOutput) {

tests/indexer/IndexerTest.php

@@ -1,18 +1,18 @@
 <?php
 
-use TeamTNT\TNTSearch\TNTSearch;
 use TeamTNT\TNTSearch\Indexer\TNTIndexer;
+use TeamTNT\TNTSearch\TNTSearch;
 
 class TNTIndexerTest extends PHPUnit_Framework_TestCase
-{   
+{
     protected $indexName = "testIndex";
-    protected $config = [
+    protected $config    = [
         'driver'   => 'sqlite',
-        'database' => __DIR__.'/../_files/articles.sqlite',
+        'database' => __DIR__ . '/../_files/articles.sqlite',
         'host'     => 'localhost',
         'username' => 'testUser',
         'password' => 'testPass',
-        'storage'  => __DIR__.'/../_files/'
+        'storage'  => __DIR__ . '/../_files/',
     ];
 
     public function testSearch()
@@ -21,14 +21,14 @@ public function testSearch()
 
         $tnt->loadConfig($this->config);
 
-        $indexer = $tnt->createIndex($this->indexName);
+        $indexer                = $tnt->createIndex($this->indexName);
         $indexer->disableOutput = true;
         $indexer->query('SELECT id, title, article FROM articles;');
         $indexer->run();
 
         $tnt->selectIndex($this->indexName);
         $tnt->asYouType = true;
-        $res = $tnt->search('Juliet');
+        $res            = $tnt->search('Juliet');
         $this->assertEquals([9, 5, 6, 7, 8, 10], $res['ids']);
 
         $res = $tnt->search('Queen Mab');
@@ -40,24 +40,24 @@ public function testBreakIntoTokens()
         $indexer = new TNTIndexer;
 
         $text = "This is some text";
-        $res = $indexer->breakIntoTokens($text);
+        $res  = $indexer->breakIntoTokens($text);
 
         $this->assertContains("This", $res);
         $this->assertContains("text", $res);
 
         $text = "123 123 123";
-        $res = $indexer->breakIntoTokens($text);
+        $res  = $indexer->breakIntoTokens($text);
         $this->assertContains("123", $res);
 
         $text = "Hi! This text contains an [email protected]. Test's email 123.";
-        $res = $indexer->breakIntoTokens($text);
+        $res  = $indexer->breakIntoTokens($text);
         $this->assertContains("test", $res);
         $this->assertContains("email", $res);
         $this->assertContains("contains", $res);
         $this->assertContains("123", $res);
 
         $text = "Superman (1941)";
-        $res = $indexer->breakIntoTokens($text);
+        $res  = $indexer->breakIntoTokens($text);
         $this->assertContains("Superman", $res);
         $this->assertContains("1941", $res);
     }
@@ -75,9 +75,9 @@ public function testIfCroatianStemmerIsSet()
         $indexer->run();
 
         $this->index = new PDO('sqlite:' . $this->config['storage'] . $this->indexName);
-        $query = "SELECT * FROM info WHERE key = 'stemmer'";
-        $docs = $this->index->query($query);
-        $value = $docs->fetch(PDO::FETCH_ASSOC)['value'];
+        $query       = "SELECT * FROM info WHERE key = 'stemmer'";
+        $docs        = $this->index->query($query);
+        $value       = $docs->fetch(PDO::FETCH_ASSOC)['value'];
         $this->assertEquals('croatian', $value);
     }
 
@@ -94,16 +94,41 @@ public function testIfGermanStemmerIsSet()
         $indexer->run();
 
         $this->index = new PDO('sqlite:' . $this->config['storage'] . $this->indexName);
-        $query = "SELECT * FROM info WHERE key = 'stemmer'";
-        $docs = $this->index->query($query);
-        $value = $docs->fetch(PDO::FETCH_ASSOC)['value'];
+        $query       = "SELECT * FROM info WHERE key = 'stemmer'";
+        $docs        = $this->index->query($query);
+        $value       = $docs->fetch(PDO::FETCH_ASSOC)['value'];
         $this->assertEquals('german', $value);
     }
 
+    public function testBuildTrigrams()
+    {
+        $indexer  = new TNTIndexer;
+        $trigrams = $indexer->buildTrigrams('created');
+        $this->assertEquals('__c _cr cre rea eat ate ted ed_ d__', $trigrams);
+
+        $trigrams = $indexer->buildTrigrams('mood');
+        $this->assertEquals('__m _mo moo ood od_ d__', $trigrams);
+
+        $trigrams = $indexer->buildTrigrams('death');
+        $this->assertEquals('__d _de dea eat ath th_ h__', $trigrams);
+
+        $trigrams = $indexer->buildTrigrams('behind');
+        $this->assertEquals('__b _be beh ehi hin ind nd_ d__', $trigrams);
+
+        $trigrams = $indexer->buildTrigrams('usually');
+        $this->assertEquals('__u _us usu sua ual all lly ly_ y__', $trigrams);
+
+        $trigrams = $indexer->buildTrigrams('created');
+        $this->assertEquals('__c _cr cre rea eat ate ted ed_ d__', $trigrams);
+
+    }
+
     public function tearDown()
     {
-        if(file_exists(__DIR__.'/../_files/'.$this->indexName))
-            unlink(__DIR__.'/../_files/'.$this->indexName);
+        if (file_exists(__DIR__ . '/../_files/' . $this->indexName)) {
+            unlink(__DIR__ . '/../_files/' . $this->indexName);
+        }
+
     }
 
-}
+}