PHPUnit a testovanie existujúcich metod

<?
class Article {

    public function createNewArticle($title, $HTMLtext, $author, $category_id) { // add a new article to DB
        $db = mysqli_connect("localhost", "root", "", "webicon_articles");
        $query = mysqli_query($db, "INSERT INTO articles (title, HTMLtext, author, category_id) VALUES 
                             ('".$title."', '".$HTMLtext."', '".$author."', '".$category_id."')");
        if($query)
            echo "The article was saved...";
        else 
            echo "ERROR! Article wasn't saved";
    }

    public function printArticle($article_id) {
        $db = mysqli_connect("localhost", "root", "", "webicon_articles");
        $query = mysqli_query($db, "SELECT * FROM articles WHERE article_id = ".$article_id);
        $row = mysqli_fetch_assoc($query);
        print "
            Title: <h2>".$row["title"]."</h2>
            <p>".$row["HTMLtext"]."</p>
            <b>Author:</b> ".$row["author"]."<br>
            <b>Category ID:</b> ".$row["category_id"]."
        ";
    }

    static function returnAllArticles() {
        $db = mysqli_connect("localhost", "root", "", "webicon_articles");
        $query = mysqli_query($db, "SELECT * FROM articles");
        print "<table>";
        while($row = mysqli_fetch_object($query)) {
            print "
                <tr><td>".$row->title."
                    <td>".$row->HTMLtext."  
                    <td>".$row->author."
                    <td>".$row->category_id."
                </tr>
            ";
        }
        print "</table>";
    }

}

<?php
class ArticleTest extends PHPUnit_Framework_TestCase {
    public function testCreateNewArticle() {
        $title = "New Article No.1";
        $HTMLtext = "In ac iaculis tellus, id sagittis ex. Donec quis lorem quam. Sed vel sem nec odio gravida lobortis. Suspendisse varius cursus elementum. In nec aliquam ipsum, a vulputate magna. Vivamus hendrerit, nulla id efficitur lobortis, tortor erat ultrices leo, vel molestie nulla erat sed est. Curabitur et tellus sed est fermentum iaculis sed at est.";
        $author = "Issac Newton";
        $category_id = 12;
        $this->createNewArticle($title, $HTMLtext, $author, $category_id);
    }
}
?>