diff -aurN a/HTML/Template/Sigma.php b/HTML/Template/Sigma.php
--- a/HTML/Template/Sigma.php	2014-01-13 04:33:52.000000000 -0500
+++ b/HTML/Template/Sigma.php	2018-02-19 09:29:52.995013991 -0500
@@ -384,6 +384,26 @@
      *
      * @see   setRoot(), setCacheRoot()
      */
+    function __construct($root = '', $cacheRoot = '')
+    {
+        // the class is inherited from PEAR to be able to use $this->setErrorHandling()
+        parent::__construct();
+        $this->variablesRegExp       = '@' . $this->openingDelimiter . '(' . $this->variablenameRegExp . ')' .
+                                       '(:(' . $this->functionnameRegExp . '))?' . $this->closingDelimiter . '@sm';
+        $this->removeVariablesRegExp = '@' . $this->openingDelimiter . '\s*(' . $this->variablenameRegExp . ')\s*'
+                                       . $this->closingDelimiter . '@sm';
+        $this->blockRegExp           = '@<!--\s+BEGIN\s+(' . $this->blocknameRegExp
+                                       . ')\s+-->(.*)<!--\s+END\s+\1\s+-->@sm';
+        $this->functionRegExp        = '@' . $this->functionPrefix . '(' . $this->functionnameRegExp . ')\s*\(@sm';
+        $this->setRoot($root);
+        $this->setCacheRoot($cacheRoot);
+
+        $this->setCallbackFunction('h', array(&$this, '_htmlspecialchars'));
+        $this->setCallbackFunction('e', array(&$this, '_htmlentities'));
+        $this->setCallbackFunction('u', 'urlencode');
+        $this->setCallbackFunction('r', 'rawurlencode');
+        $this->setCallbackFunction('j', array(&$this, '_jsEscape'));
+    }
     function HTML_Template_Sigma($root = '', $cacheRoot = '')
     {
         // the class is inherited from PEAR to be able to use $this->setErrorHandling()
diff -aurN a/tests/AllTests.php b/tests/AllTests.php
--- a/tests/AllTests.php	2014-01-13 04:33:52.000000000 -0500
+++ b/tests/AllTests.php	2018-02-19 09:37:14.071972780 -0500
@@ -24,8 +24,6 @@
     define('PHPUnit_MAIN_METHOD', 'HTML_Template_Sigma_AllTests::main');
 }
 
-require_once 'PHPUnit/Autoload.php';
-
 /**
  * Class for file / directory manipulation from PEAR package
  */