diff --git a/MathFormatter.php b/MathFormatter.php
index d7c4826..93802ef 100644
--- a/MathFormatter.php
+++ b/MathFormatter.php
@@ -2,7 +2,6 @@
 
 use DataValues\StringValue;
 use ValueFormatters\Exceptions\MismatchingDataValueTypeException;
-use ValueFormatters\FormattingException;
 use ValueFormatters\ValueFormatter;
 use Wikibase\Lib\SnakFormatter;
 
@@ -17,22 +16,25 @@ use Wikibase\Lib\SnakFormatter;
 
 class MathFormatter implements ValueFormatter {
 
+	/**
+	 * @var string One of the SnakFormatter::FORMAT_... constants.
+	 */
 	private $format;
 
-	/*
+	/**
 	 * Loads format to distinguish the type of formatting
 	 *
-	 * @param string $format
+	 * @param string $format One of the SnakFormatter::FORMAT_... constants.
 	 *
 	 * @throws InvalidArgumentException
 	 */
 	public function __construct( $format ) {
 		switch ( $format ) {
-			case ( SnakFormatter::FORMAT_HTML ):
-			case ( SnakFormatter::FORMAT_HTML_DIFF ):
-			case ( SnakFormatter::FORMAT_HTML_WIDGET ):
-			case ( SnakFormatter::FORMAT_WIKI ):
-			case ( SnakFormatter::FORMAT_PLAIN ):
+			case SnakFormatter::FORMAT_PLAIN:
+			case SnakFormatter::FORMAT_WIKI:
+			case SnakFormatter::FORMAT_HTML:
+			case SnakFormatter::FORMAT_HTML_DIFF:
+			case SnakFormatter::FORMAT_HTML_WIDGET:
 				$this->format = $format;
 				break;
 			default:
@@ -40,44 +42,40 @@ class MathFormatter implements ValueFormatter {
 		}
 	}
 
-	/*
-	 *
+	/**
 	 * @param StringValue $value
 	 *
+	 * @throws MismatchingDataValueTypeException
 	 * @return string
-	 * @throws \ValueFormatters\Exceptions\MismatchingDataValueTypeException
 	 */
 	public function format( $value ) {
 		if ( !( $value instanceof StringValue ) ) {
 			throw new MismatchingDataValueTypeException( 'StringValue', get_class( $value ) );
 		}
+
 		$tex = $value->getValue();
 
 		switch ( $this->format ) {
-			case ( SnakFormatter::FORMAT_PLAIN ):
-				return "$tex";
-			case ( SnakFormatter::FORMAT_WIKI ):
+			case SnakFormatter::FORMAT_PLAIN:
+				return $tex;
+			case SnakFormatter::FORMAT_WIKI:
 				return "<math>$tex</math>";
-			case ( SnakFormatter::FORMAT_HTML ):
-			case ( SnakFormatter::FORMAT_HTML_WIDGET ):
-			case ( SnakFormatter::FORMAT_HTML_DIFF ):
+			default:
 				$renderer = new MathMathML( $tex );
-				if ( $renderer->checkTex() ) {
-					if ( $renderer->render() ) {
-						return $renderer->getHtmlOutput();
-					}
+				if ( $renderer->checkTex() && $renderer->render() ) {
+					return $renderer->getHtmlOutput();
 				}
+
 				// TeX string is not valid or rendering failed
 				return $renderer->getLastError();
 		}
 	}
 
 	/**
-	 *
-	 * @return format
+	 * @return string One of the SnakFormatter::FORMAT_... constants.
 	 */
-
 	public function getFormat() {
 		return $this->format;
 	}
+
 }
diff --git a/MathInputCheckRestbase.php b/MathInputCheckRestbase.php
index 0fd2bc5..eb70d66 100644
--- a/MathInputCheckRestbase.php
+++ b/MathInputCheckRestbase.php
@@ -9,8 +9,6 @@
  * @author Moritz Schubotz
  */
 
-use MediaWiki\Logger\LoggerFactory;
-
 class MathInputCheckRestbase extends MathInputCheck {
 	private $restbaseInterface;
 
diff --git a/tests/MathFormatterTest.php b/tests/MathFormatterTest.php
index 9a499ce..6e19c3b 100644
--- a/tests/MathFormatterTest.php
+++ b/tests/MathFormatterTest.php
@@ -9,12 +9,8 @@ use DataValues\StringValue;
 use DataValues\NumberValue;
 
 class MathFormatterTest extends MediaWikiTestCase {
-	const SOME_TEX = "a^2+b^2=c^2";
-	const FORMAT_PLAIN = 'text/plain';
-	const FORMAT_HTML = 'text/html';
-	const FORMAT_XWIKI = 'text/x-wiki';
-	const FORMAT_UNKNOWN = 'unknown/unknown';
-	const FORMAT_VALUE = "";
+
+	const SOME_TEX = 'a^2+b^2=c^2';
 
 	protected static $hasRestbase;
 
@@ -23,19 +19,12 @@ class MathFormatterTest extends MediaWikiTestCase {
 		self::$hasRestbase = $rbi->checkBackend( true );
 	}
 
-	/**
-	 * Sets up the fixture, for example, opens a network connection.
-	 * This method is called before a test is executed.
-	 */
 	protected function setUp() {
 		parent::setUp();
-		if ( !self::$hasRestbase ) {
-			$this->markTestSkipped( "Can not connect to Restbase Math interface." );
-		}
-	}
 
-	protected function tearDown() {
-		parent::tearDown();
+		if ( !self::$hasRestbase ) {
+			$this->markTestSkipped( 'Can not connect to Restbase Math interface.' );
+		}
 	}
 
 	/**
@@ -43,16 +32,16 @@ class MathFormatterTest extends MediaWikiTestCase {
 	 * @covers MathFormatter::__construct()
 	 */
 	public function testBasics() {
-		$formatter = new MathFormatter( self::FORMAT_PLAIN );
+		$formatter = new MathFormatter( 'text/plain' );
 		// check if the format input was corretly passed to the class
-		$this->assertEquals( self::FORMAT_PLAIN, $formatter->getFormat(), 'test getFormat' );
+		$this->assertSame( 'text/plain', $formatter->getFormat(), 'test getFormat' );
 	}
 
 	/**
 	 * @expectedException ValueFormatters\Exceptions\MismatchingDataValueTypeException
 	 */
 	public function testNotStringValue() {
-		$formatter = new MathFormatter( self::FORMAT_PLAIN );
+		$formatter = new MathFormatter( 'text/plain' );
 		$formatter->format( new NumberValue( 0 ) );
 	}
 
@@ -60,7 +49,7 @@ class MathFormatterTest extends MediaWikiTestCase {
 	 * @expectedException ValueFormatters\Exceptions\MismatchingDataValueTypeException
 	 */
 	public function testNullValue() {
-		$formatter = new MathFormatter( self::FORMAT_PLAIN );
+		$formatter = new MathFormatter( 'text/plain' );
 		$formatter->format( null );
 	}
 
@@ -68,33 +57,29 @@ class MathFormatterTest extends MediaWikiTestCase {
 	 * @expectedException InvalidArgumentException
 	 */
 	public function testUnknownFormat() {
-		$formatter = new MathFormatter( self::FORMAT_UNKNOWN );
+		new MathFormatter( 'unknown/unknown' );
 	}
 
 	public function testFormatPlain() {
-		$formatter = new MathFormatter( self::FORMAT_PLAIN );
+		$formatter = new MathFormatter( 'text/plain' );
 		$value = new StringValue( self::SOME_TEX );
 		$resultFormat = $formatter->format( $value );
-		$this->assertEquals( self::SOME_TEX, $resultFormat,
-			'Results should be equal' );
-
+		$this->assertSame( self::SOME_TEX, $resultFormat );
 	}
 
 	public function testFormatHtml() {
-		$formatter = new MathFormatter( self::FORMAT_HTML );
+		$formatter = new MathFormatter( 'text/html' );
 		$value = new StringValue( self::SOME_TEX );
 		$resultFormat = $formatter->format( $value );
-		$this->assertContains( '</math>', $resultFormat,
-			'Result must contain math-tag' );
+		$this->assertContains( '</math>', $resultFormat, 'Result must contain math-tag' );
 	}
 
 	public function testFormatXWiki() {
 		$tex = self::SOME_TEX;
-		$formatter = new MathFormatter( self::FORMAT_XWIKI );
+		$formatter = new MathFormatter( 'text/x-wiki' );
 		$value = new StringValue( self::SOME_TEX );
 		$resultFormat = $formatter->format( $value );
-		$this->assertEquals( "<math>$tex</math>", $resultFormat,
-			'Tex wasn\'t properly wrapped' );
-
+		$this->assertSame( "<math>$tex</math>", $resultFormat, 'Tex wasn\'t properly wrapped' );
 	}
+
 }