public function testMatchPhrasePrefix()
 {
     $phrase = str_repeat(uniqid(' '), 4);
     $maxExpansions = rand(1, 5);
     $expectedQuery = ['match_phrase_prefix' => ['description' => ['query' => $phrase, 'max_expansions' => $maxExpansions]]];
     $this->queryBuilder->matchPhrasePrefix('description', $phrase, $maxExpansions);
     $this->assertExpectedQuery($expectedQuery);
 }