diff --git a/min_unit_tests/test_Minify_HTML_Helper.php b/min_unit_tests/test_Minify_HTML_Helper.php
deleted file mode 100644
index 47ea1ac..0000000
--- a/min_unit_tests/test_Minify_HTML_Helper.php
+++ /dev/null
@@ -1,72 +0,0 @@
-<?php
-require_once '_inc.php';
-
-function test_Minify_HTML_Helper()
-{
-    global $thisDir;
-    
-    $realDocRoot = $_SERVER['DOCUMENT_ROOT'];
-    $_SERVER['DOCUMENT_ROOT'] = $thisDir;
-
-    $file1 = $thisDir . '/_test_files/css/paths_prepend.css';
-    $file2 = $thisDir . '/_test_files/css/styles.css';
-    $maxTime = max(filemtime($file1), filemtime($file2));
-
-    $uri1 = '//_test_files/css/paths_prepend.css';
-    $uri2 = '//_test_files/css/styles.css';
-
-    $expected = "/min/b=_test_files/css&amp;f=paths_prepend.css,styles.css&amp;{$maxTime}";
-    $actual = Minify_HTML_Helper::getUri(array($uri1, $uri2));
-    $passed = assertTrue($actual === $expected, 'Minify_HTML_Helper : given URIs');
-
-    $expected = "/min/b=_test_files/css&amp;f=paths_prepend.css,styles.css&amp;{$maxTime}";
-    $actual = Minify_HTML_Helper::getUri(array($file1, $file2));
-    $passed = assertTrue($actual === $expected, 'Minify_HTML_Helper : given filepaths');
-
-    $expected = "/min/g=notRealGroup&amp;debug";
-    $actual = Minify_HTML_Helper::getUri('notRealGroup', array('debug' => true));
-    $passed = assertTrue($actual === $expected, 'Minify_HTML_Helper : non-existent group & debug');
-
-    $expected = "/myApp/min/?g=css&amp;{$maxTime}";
-    $actual = Minify_HTML_Helper::getUri('css', array(
-        'rewriteWorks' => false
-        ,'minAppUri' => '/myApp/min/'
-        ,'groupsConfigFile' => $thisDir . '/_test_files/htmlHelper_groupsConfig.php'
-    ));
-    $passed = assertTrue($actual === $expected, 'Minify_HTML_Helper : existing group');
-
-    $utilsFile = dirname(__DIR__) . '/min/utils.php';
-    if (is_file($utilsFile)) {
-        require_once $utilsFile;
-
-        $fiveSecondsAgo = $_SERVER['REQUEST_TIME'] - 5;
-        $obj = new Minify_Source(array(
-            'id' => '1',
-            'content' => '1',
-            'lastModified' => $fiveSecondsAgo,
-        ));
-
-        $output = Minify_mtime(array(
-            $uri1
-            ,$uri2
-            ,$obj
-        ));
-        $passed = assertTrue($output === $fiveSecondsAgo, 'utils.php : Minify_mtime w/ files & obj');
-
-        $obj = new Minify_Source(array(
-            'id' => '2',
-            'content' => '2',
-            'lastModified' => strtotime('2000-01-01'),
-        ));
-        $output = Minify_mtime(array(
-            $obj
-            ,'css'
-        ), $thisDir . '/_test_files/htmlHelper_groupsConfig.php');
-        $passed = assertTrue($output === $maxTime, 'utils.php : Minify_mtime w/ obj & group');
-
-    }
-
-    $_SERVER['DOCUMENT_ROOT'] = $realDocRoot;
-}
-
-test_Minify_HTML_Helper();
\ No newline at end of file
diff --git a/min_unit_tests/test_all.php b/min_unit_tests/test_all.php
index 7197c4c..b4e5436 100644
--- a/min_unit_tests/test_all.php
+++ b/min_unit_tests/test_all.php
@@ -1,7 +1,6 @@
 <?php
 
 require 'test_Minify.php';
-require 'test_Minify_HTML_Helper.php';
 require 'test_Minify_CSS.php';
 require 'test_Minify_CSS_UriRewriter.php';
 require 'test_Minify_HTML.php';
diff --git a/tests/MinifyHTMLHelperTest.php b/tests/MinifyHTMLHelperTest.php
new file mode 100644
index 0000000..14bd7d4
--- /dev/null
+++ b/tests/MinifyHTMLHelperTest.php
@@ -0,0 +1,75 @@
+<?php
+
+class MinifyHTMLHelperTest extends TestCase
+{
+    private $realDocRoot;
+
+    public function setUp()
+    {
+        $this->realDocRoot = $_SERVER['DOCUMENT_ROOT'];
+        $_SERVER['DOCUMENT_ROOT'] = self::$document_root;
+    }
+
+    // TODO: this is probably not needed if backupGlobals is enabled?
+    public function tearDown()
+    {
+        $_SERVER['DOCUMENT_ROOT'] = $this->realDocRoot;
+    }
+
+    public function test1()
+    {
+        $file1 = self::$test_files . '/css/paths_prepend.css';
+        $file2 = self::$test_files . '/css/styles.css';
+        $maxTime = max(filemtime($file1), filemtime($file2));
+
+        $uri1 = '//_test_files/css/paths_prepend.css';
+        $uri2 = '//_test_files/css/styles.css';
+
+        $expected = "/min/b=_test_files/css&amp;f=paths_prepend.css,styles.css&amp;{$maxTime}";
+        $actual = Minify_HTML_Helper::getUri(array($uri1, $uri2));
+        $this->assertEquals($expected, $actual, 'given URIs');
+
+        $expected = "/min/b=_test_files/css&amp;f=paths_prepend.css,styles.css&amp;{$maxTime}";
+        $actual = Minify_HTML_Helper::getUri(array($file1, $file2));
+        $this->assertEquals($expected, $actual, 'given filepaths');
+
+        $expected = "/min/g=notRealGroup&amp;debug";
+        $actual = Minify_HTML_Helper::getUri('notRealGroup', array('debug' => true));
+        $this->assertEquals($expected, $actual, 'non-existent group & debug');
+
+        $expected = "/myApp/min/?g=css&amp;{$maxTime}";
+        $actual = Minify_HTML_Helper::getUri('css', array(
+            'rewriteWorks' => false
+        , 'minAppUri' => '/myApp/min/'
+        , 'groupsConfigFile' => self::$test_files . '/htmlHelper_groupsConfig.php'
+        ));
+        $this->assertEquals($expected, $actual, 'existing group');
+
+
+        $utilsFile = dirname(__DIR__) . '/min/utils.php';
+        if (is_file($utilsFile)) {
+            require_once $utilsFile;
+
+            $fiveSecondsAgo = $_SERVER['REQUEST_TIME'] - 5;
+            $obj = new Minify_Source(array(
+                'id' => '1',
+                'content' => '1',
+                'lastModified' => $fiveSecondsAgo,
+            ));
+
+            $output = Minify_mtime(array($uri1, $uri2, $obj));
+            $this->assertEquals($fiveSecondsAgo, $output, 'utils.php : Minify_mtime w/ files & obj');
+
+            $obj = new Minify_Source(array(
+                'id' => '2',
+                'content' => '2',
+                'lastModified' => strtotime('2000-01-01'),
+            ));
+            $output = Minify_mtime(array(
+                $obj
+            , 'css'
+            ), self::$test_files . '/htmlHelper_groupsConfig.php');
+            $this->assertEquals($maxTime, $output, 'utils.php : Minify_mtime w/ obj & group');
+        }
+    }
+}
\ No newline at end of file
diff --git a/tests/TestCase.php b/tests/TestCase.php
index 0653a82..6891dbe 100644
--- a/tests/TestCase.php
+++ b/tests/TestCase.php
@@ -2,12 +2,15 @@
 
 class TestCase extends PHPUnit_Framework_TestCase
 {
+    /** @var string */
+    protected static $document_root;
     /** @var string */
     protected static $test_files;
 
     public static function setupBeforeClass()
     {
-        self::$test_files = __DIR__ . '/../min_unit_tests/_test_files';
+        self::$document_root = __DIR__ . '/../min_unit_tests';
+        self::$test_files = self::$document_root . '/_test_files';
     }
 
     /**