function testAddDocument()
 {
     $this->store->clear();
     $tokenizer = new Tokenizer\PorterTokenizer();
     $document = new Document('test', 'this is a test document');
     $document->id = 1;
     $document->tokens = $tokenizer->tokenize($document->content);
     $this->store->addDocument($document);
     $this->assertEquals(1, $this->store->size());
     $d = $this->store->getDocument(1);
     $this->assertEquals($document, $d);
     if (Env::isSQLite()) {
         $this->setExpectedException('Exception', "UNIQUE constraint failed");
     } else {
         $this->setExpectedException('Exception', "Duplicate entry '1' for key 'id'");
     }
     $this->store->addDocument($document);
     $this->store->clear();
     $this->assertEquals(0, $this->store->size());
 }