diff --git a/composer.json b/composer.json
index cc00a4dbf..409ce8a38 100644
--- a/composer.json
+++ b/composer.json
@@ -30,7 +30,7 @@
         "sebastian/version": ">=1.0.0"
     },
     "require-dev": {
-        "phpunit/phpunit": "4.0.*@dev",
+        "phpunit/phpunit": "4.1.*@dev",
         "ext-xdebug": ">=2.1.4"
     },
     "suggest": {
diff --git a/src/CodeCoverage/Filter.php b/src/CodeCoverage/Filter.php
index 361ca48a2..4f9f8055f 100644
--- a/src/CodeCoverage/Filter.php
+++ b/src/CodeCoverage/Filter.php
@@ -218,7 +218,8 @@ public function removeFileFromWhitelist($filename)
     /**
      * Checks whether a filename is a real filename.
      *
-     * @param string $filename
+     * @param  string $filename
+     * @return boolean
      */
     public function isFile($filename)
     {
@@ -240,8 +241,7 @@ public function isFile($filename)
      * When the whitelist is empty (default), blacklisting is used.
      * When the whitelist is not empty, whitelisting is used.
      *
-     * @param  string                     $filename
-     * @param  boolean                    $ignoreWhitelist
+     * @param  string $filename
      * @return boolean
      * @throws PHP_CodeCoverage_Exception
      */
@@ -314,6 +314,7 @@ private function prefillBlacklist()
         $this->addDirectoryContainingClassToBlacklist('Symfony\Component\Yaml\Yaml');
         $this->addDirectoryContainingClassToBlacklist('SebastianBergmann\Diff');
         $this->addDirectoryContainingClassToBlacklist('SebastianBergmann\Environment\Runtime');
+        $this->addDirectoryContainingClassToBlacklist('SebastianBergmann\Comparator\Comparator');
         $this->addDirectoryContainingClassToBlacklist('SebastianBergmann\Exporter\Exporter');
         $this->addDirectoryContainingClassToBlacklist('SebastianBergmann\Version');
         $this->addDirectoryContainingClassToBlacklist('Composer\Autoload\ClassLoader');
diff --git a/src/CodeCoverage/Report/Factory.php b/src/CodeCoverage/Report/Factory.php
index c8cb63b4b..72b974a84 100644
--- a/src/CodeCoverage/Report/Factory.php
+++ b/src/CodeCoverage/Report/Factory.php
@@ -57,7 +57,8 @@
 class PHP_CodeCoverage_Report_Factory
 {
     /**
-     * @param PHP_CodeCoverage $coverage
+     * @param  PHP_CodeCoverage $coverage
+     * @return PHP_CodeCoverage_Report_Node_Directory
      */
     public function create(PHP_CodeCoverage $coverage)
     {
diff --git a/src/CodeCoverage/Report/HTML/Renderer.php b/src/CodeCoverage/Report/HTML/Renderer.php
index 90f8aa4cb..598b10a7e 100644
--- a/src/CodeCoverage/Report/HTML/Renderer.php
+++ b/src/CodeCoverage/Report/HTML/Renderer.php
@@ -99,7 +99,7 @@ abstract class PHP_CodeCoverage_Report_HTML_Renderer
      */
     public function __construct($templatePath, $generator, $date, $lowUpperBound, $highLowerBound)
     {
-        $version = new SebastianBergmann\Version('2.0', __DIR__);
+        $version = new SebastianBergmann\Version('2.1', __DIR__);
 
         $this->templatePath   = $templatePath;
         $this->generator      = $generator;
@@ -211,6 +211,10 @@ protected function setCommonTemplateVariables(Text_Template $template, PHP_CodeC
         );
     }
 
+    /**
+     * @param  PHP_CodeCoverage_Report_Node $node
+     * @return string
+     */
     protected function getBreadcrumbs(PHP_CodeCoverage_Report_Node $node)
     {
         $breadcrumbs = '';
@@ -239,6 +243,10 @@ protected function getBreadcrumbs(PHP_CodeCoverage_Report_Node $node)
         return $breadcrumbs;
     }
 
+    /**
+     * @param  PHP_CodeCoverage_Report_Node $node
+     * @return string
+     */
     protected function getActiveBreadcrumb(PHP_CodeCoverage_Report_Node $node)
     {
         $buffer = sprintf(
@@ -253,6 +261,11 @@ protected function getActiveBreadcrumb(PHP_CodeCoverage_Report_Node $node)
         return $buffer;
     }
 
+    /**
+     * @param  PHP_CodeCoverage_Report_Node $node
+     * @param  $pathToRoot
+     * @return string
+     */
     protected function getInactiveBreadcrumb(PHP_CodeCoverage_Report_Node $node, $pathToRoot)
     {
         return sprintf(
@@ -262,6 +275,10 @@ protected function getInactiveBreadcrumb(PHP_CodeCoverage_Report_Node $node, $pa
         );
     }
 
+    /**
+     * @param  PHP_CodeCoverage_Report_Node $node
+     * @return string
+     */
     protected function getPathToRoot(PHP_CodeCoverage_Report_Node $node)
     {
         $id    = $node->getId();
@@ -275,6 +292,10 @@ protected function getPathToRoot(PHP_CodeCoverage_Report_Node $node)
         return str_repeat('../', $depth);
     }
 
+    /**
+     * @param  float $percent
+     * @return string
+     */
     protected function getCoverageBar($percent)
     {
         $level = $this->getColorLevel($percent);
diff --git a/src/CodeCoverage/Report/HTML/Renderer/Dashboard.php b/src/CodeCoverage/Report/HTML/Renderer/Dashboard.php
index dbf21252e..1c2f1fd55 100644
--- a/src/CodeCoverage/Report/HTML/Renderer/Dashboard.php
+++ b/src/CodeCoverage/Report/HTML/Renderer/Dashboard.php
@@ -175,7 +175,7 @@ protected function coverageDistribution(array $classes)
         );
 
         foreach ($classes as $class) {
-            foreach ($class['methods'] as $methodName => $method) {
+            foreach ($class['methods'] as $method) {
                 if ($method['coverage'] == 0) {
                     $result['method']['0%']++;
                 } elseif ($method['coverage'] == 100) {
@@ -318,6 +318,10 @@ protected function projectRisks(array $classes)
         return $result;
     }
 
+    /**
+     * @param  PHP_CodeCoverage_Report_Node $node
+     * @return string
+     */
     protected function getActiveBreadcrumb(PHP_CodeCoverage_Report_Node $node)
     {
         return sprintf(
diff --git a/src/CodeCoverage/Report/HTML/Renderer/File.php b/src/CodeCoverage/Report/HTML/Renderer/File.php
index 8c73f8f63..b8a119655 100644
--- a/src/CodeCoverage/Report/HTML/Renderer/File.php
+++ b/src/CodeCoverage/Report/HTML/Renderer/File.php
@@ -272,6 +272,8 @@ protected function renderFunctionItems(array $functions, Text_Template $template
 
     /**
      * @param  Text_Template $template
+     * @param  array         $item
+     * @param  string        $indent
      * @return string
      */
     protected function renderFunctionOrMethodItem(Text_Template $template, array $item, $indent = '')
@@ -329,7 +331,6 @@ protected function renderSource(PHP_CodeCoverage_Report_Node_File $node)
         $i            = 1;
 
         foreach ($codeLines as $line) {
-            $numTests       = '';
             $trClass        = '';
             $popoverContent = '';
             $popoverTitle   = '';
diff --git a/src/CodeCoverage/Util.php b/src/CodeCoverage/Util.php
index f17904279..8cf922389 100644
--- a/src/CodeCoverage/Util.php
+++ b/src/CodeCoverage/Util.php
@@ -57,8 +57,10 @@
 class PHP_CodeCoverage_Util
 {
     /**
-     * @param  float $a
-     * @param  float $b
+     * @param  float   $a
+     * @param  float   $b
+     * @param  boolean $asString
+     * @param  boolean $fixedWidth
      * @return float ($a / $b) * 100
      */
     public static function percent($a, $b, $asString = false, $fixedWidth = false)
diff --git a/src/CodeCoverage/Util/InvalidArgumentHelper.php b/src/CodeCoverage/Util/InvalidArgumentHelper.php
index 6637a978d..7cd5e712c 100644
--- a/src/CodeCoverage/Util/InvalidArgumentHelper.php
+++ b/src/CodeCoverage/Util/InvalidArgumentHelper.php
@@ -58,9 +58,10 @@
 class PHP_CodeCoverage_Util_InvalidArgumentHelper
 {
     /**
-     * @param integer $argument
-     * @param string  $type
-     * @param mixed   $value
+     * @param  integer $argument
+     * @param  string  $type
+     * @param  mixed   $value
+     * @return PHP_CodeCoverage_Exception
      */
     public static function factory($argument, $type, $value = null)
     {