diff --git a/local/qeupgradehelper/locallib.php b/local/qeupgradehelper/locallib.php
index 1e2b34f7027..8cba61c2a05 100755
--- a/local/qeupgradehelper/locallib.php
+++ b/local/qeupgradehelper/locallib.php
@@ -548,6 +548,7 @@ function local_qeupgradehelper_format_var($name, $var) {
     $out = preg_replace('/\n   (?! )/',       "\n            ", $out);
     $out = preg_replace('/\n  (?! )/',        "\n            ", $out);
     $out = preg_replace('/\n(?! )/',          "\n        ", $out);
+    $out = preg_replace('/\bNULL\b/', 'null', $out);
     return "        $name = $out;\n";
 }
 
diff --git a/question/category_class.php b/question/category_class.php
index b0c26e90c67..8881ce428a2 100644
--- a/question/category_class.php
+++ b/question/category_class.php
@@ -427,7 +427,7 @@ class question_category_object {
         }
 
         // Update the category record.
-        $cat = NULL;
+        $cat = null;
         $cat->id = $updateid;
         $cat->name = $newname;
         $cat->info = $newinfo;
diff --git a/question/editlib.php b/question/editlib.php
index b0b492105ce..d646644124a 100644
--- a/question/editlib.php
+++ b/question/editlib.php
@@ -1653,7 +1653,7 @@ function question_edit_setup($edittab, $baseurl, $requirecmid = false, $requirec
     $contextlist = join($contextlistarr, ' ,');
     if (!empty($pagevars['cat'])){
         $catparts = explode(',', $pagevars['cat']);
-        if (!$catparts[0] || (FALSE !== array_search($catparts[1], $contextlistarr)) ||
+        if (!$catparts[0] || (false !== array_search($catparts[1], $contextlistarr)) ||
                 !$DB->count_records_select("question_categories", "id = ? AND contextid = ?", array($catparts[0], $catparts[1]))) {
             print_error('invalidcategory', 'question');
         }
diff --git a/question/format.php b/question/format.php
index 41f52952e3e..23fbdcaaf2d 100644
--- a/question/format.php
+++ b/question/format.php
@@ -36,9 +36,9 @@ defined('MOODLE_INTERNAL') || die();
 class qformat_default {
 
     public $displayerrors = true;
-    public $category = NULL;
+    public $category = null;
     public $questions = array();
-    public $course = NULL;
+    public $course = null;
     public $filename = '';
     public $realfilename = '';
     public $matchgrades = 'error';
@@ -602,7 +602,7 @@ class qformat_default {
         $formatnotimplemented = get_string('formatnotimplemented', 'question');
         echo "<p>$formatnotimplemented</p>";
 
-        return NULL;
+        return null;
     }
 
     /**
@@ -834,7 +834,7 @@ class qformat_default {
         // if not overidden, then this is an error.
         $formatnotimplemented = get_string('formatnotimplemented', 'question');
         echo "<p>$formatnotimplemented</p>";
-        return NULL;
+        return null;
     }
 
     /**
diff --git a/question/type/calculated/edit_calculated_form.php b/question/type/calculated/edit_calculated_form.php
index ae336f7ff60..ee4c8aefe68 100644
--- a/question/type/calculated/edit_calculated_form.php
+++ b/question/type/calculated/edit_calculated_form.php
@@ -287,11 +287,11 @@ class qtype_calculated_edit_form extends qtype_numerical_edit_form {
         return $errors;
     }
 
-    function is_valid_answer($answer, $data) {
+    protected function is_valid_answer($answer, $data) {
         return !qtype_calculated_find_formula_errors($answer);
     }
 
-    function valid_answer_message($answer) {
+    protected function valid_answer_message($answer) {
         if (!$answer) {
             return get_string('mustenteraformulaorstar', 'qtype_numerical');
         } else {
diff --git a/question/type/calculated/question.php b/question/type/calculated/question.php
index b8edf48a0a1..327b365235e 100644
--- a/question/type/calculated/question.php
+++ b/question/type/calculated/question.php
@@ -81,7 +81,7 @@ class qtype_calculated_question extends qtype_numerical_question
  * is to work with {@link qtype_calculated_question_helper}.
  *
  * As well as this method, the class that implements this interface must have
- * fields 
+ * fields
  * public $datasetloader; // of type qtype_calculated_dataset_loader
  * public $vs; // of type qtype_calculated_variable_substituter
  *
@@ -322,7 +322,7 @@ class qtype_calculated_variable_substituter {
 
     /**
      * Return an array of the variables and their values.
-     * @return array name => value. 
+     * @return array name => value.
      */
     public function get_values() {
         return $this->values;
@@ -404,13 +404,13 @@ class qtype_calculated_variable_substituter {
         while (preg_match('~\\{[[:alpha:]][^>} <{"\']*\\}~', $formula, $regs)) {
             $formula = str_replace($regs[0], '1', $formula);
         }
-    
+
         // Strip away empty space and lowercase it
         $formula = strtolower(str_replace(' ', '', $formula));
-    
+
         $safeoperatorchar = '-+/*%>:^\~<?=&|!'; /* */
         $operatorornumber = "[$safeoperatorchar.0-9eE]";
-    
+
         while (preg_match("~(^|[$safeoperatorchar,(])([a-z0-9_]*)" .
                 "\\(($operatorornumber+(,$operatorornumber+((,$operatorornumber+)+)?)?)?\\)~",
             $formula, $regs)) {
@@ -421,14 +421,14 @@ class qtype_calculated_variable_substituter {
                         return get_string('illegalformulasyntax', 'qtype_calculated', $regs[0]);
                     }
                     break;
-    
+
                     // Zero argument functions
                 case 'pi':
                     if ($regs[3]) {
                         return get_string('functiontakesnoargs', 'qtype_calculated', $regs[2]);
                     }
                     break;
-    
+
                     // Single argument functions (the most common case)
                 case 'abs': case 'acos': case 'acosh': case 'asin': case 'asinh':
                 case 'atan': case 'atanh': case 'bindec': case 'ceil': case 'cos':
@@ -441,32 +441,33 @@ class qtype_calculated_variable_substituter {
                         return get_string('functiontakesonearg', 'qtype_calculated', $regs[2]);
                     }
                     break;
-    
+
                     // Functions that take one or two arguments
                 case 'log': case 'round':
                     if (!empty($regs[5]) || empty($regs[3])) {
-                        return get_string('functiontakesoneortwoargs', 'qtype_calculated', $regs[2]);
+                        return get_string('functiontakesoneortwoargs', 'qtype_calculated',
+                                $regs[2]);
                     }
                     break;
-    
+
                     // Functions that must have two arguments
                 case 'atan2': case 'fmod': case 'pow':
                     if (!empty($regs[5]) || empty($regs[4])) {
                         return get_string('functiontakestwoargs', 'qtype_calculated', $regs[2]);
                     }
                     break;
-    
+
                     // Functions that take two or more arguments
                 case 'min': case 'max':
                     if (empty($regs[4])) {
                         return get_string('functiontakesatleasttwo', 'qtype_calculated', $regs[2]);
                     }
                     break;
-    
+
                 default:
                     return get_string('unsupportedformulafunction', 'qtype_calculated', $regs[2]);
             }
-    
+
             // Exchange the function call with '1' and then chack for
             // another function call...
             if ($regs[1]) {
@@ -477,7 +478,7 @@ class qtype_calculated_variable_substituter {
                 $formula = preg_replace("~^$regs[2]\\([^)]*\\)~", '1', $formula);
             }
         }
-    
+
         if (preg_match("~[^$safeoperatorchar.0-9eE]+~", $formula, $regs)) {
             return get_string('illegalformulasyntax', 'qtype_calculated', $regs[0]);
         } else {
diff --git a/question/type/calculated/simpletest/helper.php b/question/type/calculated/simpletest/helper.php
index 4fdc0fc20ca..f4a1dca42de 100644
--- a/question/type/calculated/simpletest/helper.php
+++ b/question/type/calculated/simpletest/helper.php
@@ -54,7 +54,8 @@ class qtype_calculated_test_helper extends question_test_helper {
 
         $q->answers = array(
             13 => new qtype_numerical_answer(13, '{a} + {b}', 1.0, 'Very good.', FORMAT_HTML, 0),
-            14 => new qtype_numerical_answer(14, '{a} - {b}', 0.0, 'Add. not subtract!.', FORMAT_HTML, 0),
+            14 => new qtype_numerical_answer(14, '{a} - {b}', 0.0, 'Add. not subtract!.',
+                    FORMAT_HTML, 0),
             17 => new qtype_numerical_answer(17, '*', 0.0, 'Completely wrong.', FORMAT_HTML, 0),
         );
         foreach ($q->answers as $answer) {
diff --git a/question/type/calculatedmulti/simpletest/helper.php b/question/type/calculatedmulti/simpletest/helper.php
index ff81c3d17f9..408a7e6949e 100644
--- a/question/type/calculatedmulti/simpletest/helper.php
+++ b/question/type/calculatedmulti/simpletest/helper.php
@@ -54,7 +54,8 @@ class qtype_calculatedmulti_test_helper extends question_test_helper {
         $q->generalfeedback = 'Generalfeedback: {={a} + {b}} is the right answer.';
         $q->answers = array(
             13 => new qtype_numerical_answer(13, '{a} + {b}', 1.0, 'Very good.', FORMAT_HTML, 0),
-            14 => new qtype_numerical_answer(14, '{a} - {b}', 0.0, 'Add. not subtract!.', FORMAT_HTML, 0),
+            14 => new qtype_numerical_answer(14, '{a} - {b}', 0.0, 'Add. not subtract!.',
+                    FORMAT_HTML, 0),
             17 => new qtype_numerical_answer(17, '*', 0.0, 'Completely wrong.', FORMAT_HTML, 0),
         );
         $q->qtype = question_bank::get_qtype('calculated');
@@ -71,28 +72,3 @@ class qtype_calculatedmulti_test_helper extends question_test_helper {
         return $q;
     }
 }
-
-
-/**
- * Test implementation of {@link qtype_calculated_dataset_loader}. Gets the values
- * from an array passed to the constructor, rather than querying the database.
- *
- * @copyright  2011 The Open University
- * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- */
-class qtype_calculated_test_dataset_loader extends qtype_calculated_dataset_loader{
-    protected $valuesets;
-
-    public function __construct($questionid, array $valuesets) {
-        parent::__construct($questionid);
-        $this->valuesets = $valuesets;
-    }
-
-    public function get_number_of_items() {
-        return count($this->valuesets);
-    }
-
-    public function load_values($itemnumber) {
-        return $this->valuesets[$itemnumber - 1];
-    }
-}
diff --git a/question/type/calculatedsimple/simpletest/helper.php b/question/type/calculatedsimple/simpletest/helper.php
index 704d97964a2..1b5c0b8c18f 100644
--- a/question/type/calculatedsimple/simpletest/helper.php
+++ b/question/type/calculatedsimple/simpletest/helper.php
@@ -54,7 +54,8 @@ class qtype_calculatedsimple_test_helper extends question_test_helper {
 
         $q->answers = array(
             13 => new qtype_numerical_answer(13, '{a} + {b}', 1.0, 'Very good.', FORMAT_HTML, 0),
-            14 => new qtype_numerical_answer(14, '{a} - {b}', 0.0, 'Add. not subtract!.', FORMAT_HTML, 0),
+            14 => new qtype_numerical_answer(14, '{a} - {b}', 0.0, 'Add. not subtract!.',
+                    FORMAT_HTML, 0),
             17 => new qtype_numerical_answer(17, '*', 0.0, 'Completely wrong.', FORMAT_HTML, 0),
         );
         foreach ($q->answers as $answer) {
diff --git a/question/type/description/db/simpletest/testupgradelibnewqe.php b/question/type/description/db/simpletest/testupgradelibnewqe.php
index 9c8f8409f13..b9293df4e92 100644
--- a/question/type/description/db/simpletest/testupgradelibnewqe.php
+++ b/question/type/description/db/simpletest/testupgradelibnewqe.php
@@ -103,9 +103,9 @@ class qtype_description_attempt_upgrader_test extends question_attempt_upgrader_
             'generalfeedbackformat' => '1',
             'timecreated' => '0',
             'timemodified' => '0',
-            'createdby' => NULL,
-            'modifiedby' => NULL,
-            'unlimited' => NULL,
+            'createdby' => null,
+            'modifiedby' => null,
+            'unlimited' => null,
             'maxmark' => '1',
         );
         $qsession = (object) array(
@@ -248,9 +248,9 @@ class qtype_description_attempt_upgrader_test extends question_attempt_upgrader_
             'generalfeedbackformat' => '1',
             'timecreated' => '0',
             'timemodified' => '0',
-            'createdby' => NULL,
-            'modifiedby' => NULL,
-            'unlimited' => NULL,
+            'createdby' => null,
+            'modifiedby' => null,
+            'unlimited' => null,
             'maxmark' => '0',
         );
         $qsession = (object) array(
@@ -396,9 +396,9 @@ class qtype_description_attempt_upgrader_test extends question_attempt_upgrader_
             'generalfeedbackformat' => '1',
             'timecreated' => '0',
             'timemodified' => '0',
-            'createdby' => NULL,
-            'modifiedby' => NULL,
-            'unlimited' => NULL,
+            'createdby' => null,
+            'modifiedby' => null,
+            'unlimited' => null,
             'maxmark' => '0',
         );
         $qsession = (object) array(
diff --git a/question/type/essay/db/simpletest/testupgradelibnewqe.php b/question/type/essay/db/simpletest/testupgradelibnewqe.php
index 9f06bd4c061..141de82b312 100644
--- a/question/type/essay/db/simpletest/testupgradelibnewqe.php
+++ b/question/type/essay/db/simpletest/testupgradelibnewqe.php
@@ -337,9 +337,9 @@ class qtype_essay_attempt_upgrader_test extends question_attempt_upgrader_test_b
             'generalfeedbackformat' => '1',
             'timecreated' => '0',
             'timemodified' => '0',
-            'createdby' => NULL,
-            'modifiedby' => NULL,
-            'unlimited' => NULL,
+            'createdby' => null,
+            'modifiedby' => null,
+            'unlimited' => null,
             'maxmark' => '0',
             'options' => (object) array(
                 'answers' => array(
@@ -516,9 +516,9 @@ class qtype_essay_attempt_upgrader_test extends question_attempt_upgrader_test_b
             'generalfeedbackformat' => '1',
             'timecreated' => '0',
             'timemodified' => '0',
-            'createdby' => NULL,
-            'modifiedby' => NULL,
-            'unlimited' => NULL,
+            'createdby' => null,
+            'modifiedby' => null,
+            'unlimited' => null,
             'maxmark' => '0',
             'options' => (object) array(
                 'answers' => array(
diff --git a/question/type/match/db/simpletest/testupgradelibnewqe.php b/question/type/match/db/simpletest/testupgradelibnewqe.php
index 1b6f4f0084e..479bfe7d080 100644
--- a/question/type/match/db/simpletest/testupgradelibnewqe.php
+++ b/question/type/match/db/simpletest/testupgradelibnewqe.php
@@ -103,9 +103,9 @@ class qtype_match_attempt_upgrader_test extends question_attempt_upgrader_test_b
             'generalfeedbackformat' => '1',
             'timecreated' => '0',
             'timemodified' => '0',
-            'createdby' => NULL,
-            'modifiedby' => NULL,
-            'unlimited' => NULL,
+            'createdby' => null,
+            'modifiedby' => null,
+            'unlimited' => null,
             'maxmark' => '3',
             'options' => (object) array(
                 'id' => '27',
@@ -352,9 +352,9 @@ class qtype_match_attempt_upgrader_test extends question_attempt_upgrader_test_b
             'generalfeedbackformat' => '1',
             'timecreated' => '0',
             'timemodified' => '0',
-            'createdby' => NULL,
-            'modifiedby' => NULL,
-            'unlimited' => NULL,
+            'createdby' => null,
+            'modifiedby' => null,
+            'unlimited' => null,
             'maxmark' => '1',
             'options' => (object) array(
                 'id' => '35',
@@ -563,9 +563,9 @@ class qtype_match_attempt_upgrader_test extends question_attempt_upgrader_test_b
             'generalfeedbackformat' => '1',
             'timecreated' => '0',
             'timemodified' => '0',
-            'createdby' => NULL,
-            'modifiedby' => NULL,
-            'unlimited' => NULL,
+            'createdby' => null,
+            'modifiedby' => null,
+            'unlimited' => null,
             'maxmark' => '1',
             'options' => (object) array(
                 'id' => '279',
diff --git a/question/type/multichoice/db/simpletest/testupgradelibnewqe.php b/question/type/multichoice/db/simpletest/testupgradelibnewqe.php
index ff8540a4c4b..67c32e37367 100644
--- a/question/type/multichoice/db/simpletest/testupgradelibnewqe.php
+++ b/question/type/multichoice/db/simpletest/testupgradelibnewqe.php
@@ -162,17 +162,17 @@ class qtype_multichoice_attempt_upgrader_test extends question_attempt_upgrader_
                 1 => (object) array(
                     'hint' => 'First hint',
                     'questionid' => '2',
-                    'shownumcorrect' => NULL,
-                    'clearwrong' => NULL,
-                    'options' => NULL,
+                    'shownumcorrect' => null,
+                    'clearwrong' => null,
+                    'options' => null,
                     'id' => 1,
                 ),
                 2 => (object) array(
                     'hint' => 'Second hint',
                     'questionid' => '2',
-                    'shownumcorrect' => NULL,
-                    'clearwrong' => NULL,
-                    'options' => NULL,
+                    'shownumcorrect' => null,
+                    'clearwrong' => null,
+                    'options' => null,
                     'id' => 2,
                 ),
             ),
@@ -338,9 +338,9 @@ class qtype_multichoice_attempt_upgrader_test extends question_attempt_upgrader_
             'generalfeedbackformat' => '1',
             'timecreated' => '0',
             'timemodified' => '0',
-            'createdby' => NULL,
-            'modifiedby' => NULL,
-            'unlimited' => NULL,
+            'createdby' => null,
+            'modifiedby' => null,
+            'unlimited' => null,
             'maxmark' => '1',
             'options' => (object) array(
                 'id' => '44',
@@ -505,9 +505,9 @@ class qtype_multichoice_attempt_upgrader_test extends question_attempt_upgrader_
             'generalfeedbackformat' => '1',
             'timecreated' => '0',
             'timemodified' => '0',
-            'createdby' => NULL,
-            'modifiedby' => NULL,
-            'unlimited' => NULL,
+            'createdby' => null,
+            'modifiedby' => null,
+            'unlimited' => null,
             'maxmark' => '1',
             'options' => (object) array(
                 'id' => '152',
@@ -701,9 +701,9 @@ class qtype_multichoice_attempt_upgrader_test extends question_attempt_upgrader_
             'generalfeedbackformat' => '1',
             'timecreated' => '0',
             'timemodified' => '0',
-            'createdby' => NULL,
-            'modifiedby' => NULL,
-            'unlimited' => NULL,
+            'createdby' => null,
+            'modifiedby' => null,
+            'unlimited' => null,
             'maxmark' => '5',
             'options' => (object) array(
                 'id' => '943',
@@ -937,9 +937,9 @@ class qtype_multichoice_attempt_upgrader_test extends question_attempt_upgrader_
             'generalfeedbackformat' => '1',
             'timecreated' => '0',
             'timemodified' => '0',
-            'createdby' => NULL,
-            'modifiedby' => NULL,
-            'unlimited' => NULL,
+            'createdby' => null,
+            'modifiedby' => null,
+            'unlimited' => null,
             'maxmark' => '1',
             'options' => (object) array(
                 'id' => '44',
@@ -1071,9 +1071,9 @@ public function test_multichoice_deferredfeedback_qsession140() {
             'generalfeedbackformat' => '1',
             'timecreated' => '0',
             'timemodified' => '0',
-            'createdby' => NULL,
-            'modifiedby' => NULL,
-            'unlimited' => NULL,
+            'createdby' => null,
+            'modifiedby' => null,
+            'unlimited' => null,
             'maxmark' => '1',
             'options' => (object) array(
                 'id' => '71',
@@ -1520,7 +1520,7 @@ public function test_multichoice_deferredfeedback_qsession140() {
             'timemodified' => '1223623680',
             'createdby' => '26409',
             'modifiedby' => '351133',
-            'unlimited' => NULL,
+            'unlimited' => null,
             'maxmark' => '1',
             'options' => (object) array(
                 'id' => '23896',
@@ -1748,9 +1748,9 @@ public function test_multichoice_deferredfeedback_qsession140() {
             'generalfeedbackformat' => '1',
             'timecreated' => '0',
             'timemodified' => '0',
-            'createdby' => NULL,
-            'modifiedby' => NULL,
-            'unlimited' => NULL,
+            'createdby' => null,
+            'modifiedby' => null,
+            'unlimited' => null,
             'maxmark' => '1',
             'options' => (object) array(
                 'id' => '117',
@@ -2187,9 +2187,9 @@ public function test_multichoice_deferredfeedback_qsession140() {
             'generalfeedbackformat' => '1',
             'timecreated' => '0',
             'timemodified' => '0',
-            'createdby' => NULL,
-            'modifiedby' => NULL,
-            'unlimited' => NULL,
+            'createdby' => null,
+            'modifiedby' => null,
+            'unlimited' => null,
             'maxmark' => '5',
             'options' => (object) array(
                 'id' => '1439',
@@ -2408,9 +2408,9 @@ public function test_multichoice_deferredfeedback_qsession140() {
             'generalfeedbackformat' => '1',
             'timecreated' => '0',
             'timemodified' => '0',
-            'createdby' => NULL,
-            'modifiedby' => NULL,
-            'unlimited' => NULL,
+            'createdby' => null,
+            'modifiedby' => null,
+            'unlimited' => null,
             'maxmark' => '0',
             'options' => (object) array(
                 'id' => '180',
@@ -2618,9 +2618,9 @@ public function test_multichoice_deferredfeedback_qsession140() {
             'generalfeedbackformat' => '1',
             'timecreated' => '0',
             'timemodified' => '0',
-            'createdby' => NULL,
-            'modifiedby' => NULL,
-            'unlimited' => NULL,
+            'createdby' => null,
+            'modifiedby' => null,
+            'unlimited' => null,
             'maxmark' => '0',
             'options' => (object) array(
                 'id' => '175',
diff --git a/question/type/numerical/backup/moodle2/restore_qtype_numerical_plugin.class.php b/question/type/numerical/backup/moodle2/restore_qtype_numerical_plugin.class.php
index 44f3f3fc712..ef63583bd42 100644
--- a/question/type/numerical/backup/moodle2/restore_qtype_numerical_plugin.class.php
+++ b/question/type/numerical/backup/moodle2/restore_qtype_numerical_plugin.class.php
@@ -78,10 +78,6 @@ class restore_qtype_numerical_plugin extends restore_qtype_plugin {
             $data->answer = $this->get_mappingid('question_answer', $data->answer);
             // Insert record
             $newitemid = $DB->insert_record('question_numerical', $data);
-            // Create mapping (not needed, no files nor childs nor states here)
-            //$this->set_mapping('question_numerical', $oldid, $newitemid);
-        } else {
-            // Nothing to remap if the question already existed
         }
     }
 }
diff --git a/question/type/numerical/db/simpletest/testupgradelibnewqe.php b/question/type/numerical/db/simpletest/testupgradelibnewqe.php
index 680d620b57c..6b4a6e65bf0 100644
--- a/question/type/numerical/db/simpletest/testupgradelibnewqe.php
+++ b/question/type/numerical/db/simpletest/testupgradelibnewqe.php
@@ -135,9 +135,9 @@ class qtype_numerical_attempt_upgrader_test extends question_attempt_upgrader_te
             'generalfeedbackformat' => '1',
             'timecreated' => '0',
             'timemodified' => '0',
-            'createdby' => NULL,
-            'modifiedby' => NULL,
-            'unlimited' => NULL,
+            'createdby' => null,
+            'modifiedby' => null,
+            'unlimited' => null,
             'maxmark' => '1',
             'options' => (object) array(
                 'answers' => array(
diff --git a/question/type/numerical/db/upgrade.php b/question/type/numerical/db/upgrade.php
index 0f24ad95aa7..8e594ae084b 100644
--- a/question/type/numerical/db/upgrade.php
+++ b/question/type/numerical/db/upgrade.php
@@ -36,25 +36,32 @@ function xmldb_qtype_numerical_upgrade($oldversion) {
 
     $dbman = $DB->get_manager();
 
-//===== 1.9.0 upgrade line ======//
+    //===== 1.9.0 upgrade line ======//
     if ($oldversion < 2009100100 ) { //New version in version.php
 
-    /// Define table question_numerical_options to be created
+        // Define table question_numerical_options to be created
         $table = new xmldb_table('question_numerical_options');
 
-    /// Adding fields to table question_numerical_options
-        $table->add_field('id', XMLDB_TYPE_INTEGER, '10', XMLDB_UNSIGNED, XMLDB_NOTNULL, XMLDB_SEQUENCE, null);
-        $table->add_field('question', XMLDB_TYPE_INTEGER, '10', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, '0');
-        $table->add_field('instructions', XMLDB_TYPE_TEXT, 'small', null, null, null, null);
-        $table->add_field('showunits', XMLDB_TYPE_INTEGER, '4', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, '0');
-        $table->add_field('unitsleft', XMLDB_TYPE_INTEGER, '4', null, XMLDB_NOTNULL, null, '0');
-        $table->add_field('unitgradingtype', XMLDB_TYPE_INTEGER, '4', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, '0');
-        $table->add_field('unitpenalty', XMLDB_TYPE_NUMBER, '12, 7', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, '0.1');
+        // Adding fields to table question_numerical_options
+        $table->add_field('id', XMLDB_TYPE_INTEGER, '10', XMLDB_UNSIGNED,
+                XMLDB_NOTNULL, XMLDB_SEQUENCE, null);
+        $table->add_field('question', XMLDB_TYPE_INTEGER, '10', XMLDB_UNSIGNED,
+                XMLDB_NOTNULL, null, '0');
+        $table->add_field('instructions', XMLDB_TYPE_TEXT, 'small', null,
+                null, null, null);
+        $table->add_field('showunits', XMLDB_TYPE_INTEGER, '4', XMLDB_UNSIGNED,
+                XMLDB_NOTNULL, null, '0');
+        $table->add_field('unitsleft', XMLDB_TYPE_INTEGER, '4', null,
+                XMLDB_NOTNULL, null, '0');
+        $table->add_field('unitgradingtype', XMLDB_TYPE_INTEGER, '4', XMLDB_UNSIGNED,
+                XMLDB_NOTNULL, null, '0');
+        $table->add_field('unitpenalty', XMLDB_TYPE_NUMBER, '12, 7', XMLDB_UNSIGNED,
+                XMLDB_NOTNULL, null, '0.1');
 
-    /// Adding keys to table question_numerical_options
+        // Adding keys to table question_numerical_options
         $table->add_key('primary', XMLDB_KEY_PRIMARY, array('id'));
         $table->add_key('question', XMLDB_KEY_FOREIGN, array('question'), 'question', array('id'));
-    /// Conditionally launch create table for question_calculated_options
+        // Conditionally launch create table for question_calculated_options
         if (!$dbman->table_exists($table)) {
             // $dbman->create_table doesnt return a result, we just have to trust it
             $dbman->create_table($table);
@@ -66,7 +73,8 @@ function xmldb_qtype_numerical_upgrade($oldversion) {
 
         // Define field instructionsformat to be added to question_numerical_options
         $table = new xmldb_table('question_numerical_options');
-        $field = new xmldb_field('instructionsformat', XMLDB_TYPE_INTEGER, '2', null, XMLDB_NOTNULL, null, '0', 'instructions');
+        $field = new xmldb_field('instructionsformat', XMLDB_TYPE_INTEGER, '2', null,
+                XMLDB_NOTNULL, null, '0', 'instructions');
 
         // Conditionally launch add field instructionsformat
         if (!$dbman->field_exists($table, $field)) {
@@ -81,7 +89,8 @@ function xmldb_qtype_numerical_upgrade($oldversion) {
                 FROM {question_numerical_options} qno
                 JOIN {question} q ON qno.question = q.id');
         foreach ($rs as $record) {
-            if ($CFG->texteditors !== 'textarea' && $record->oldquestiontextformat == FORMAT_MOODLE) {
+            if ($CFG->texteditors !== 'textarea' &&
+                    $record->oldquestiontextformat == FORMAT_MOODLE) {
                 $record->instructions = text_to_html($record->questiontext, false, false, true);
                 $record->instructionsformat = FORMAT_HTML;
             } else {
@@ -159,7 +168,8 @@ function xmldb_qtype_numerical_upgrade($oldversion) {
                 }
 
                 $oldfiles = $fs->get_area_files($numericaloptions->contextid,
-                        'qtype_numerical', 'instruction', $numericaloptions->questionid, 'id', false);
+                        'qtype_numerical', 'instruction', $numericaloptions->questionid,
+                        'id', false);
                 foreach ($oldfiles as $oldfile) {
                     $filerecord = new stdClass();
                     $filerecord->component = 'question';
@@ -265,6 +275,7 @@ function qtype_numerical_convert_to_html($text, $oldformat) {
             return text_to_html($text, null, $options['para'], $options['newlines']);
 
         default:
-            throw new coding_exception('Unexpected text format when upgrading numerical questions.');
+            throw new coding_exception(
+                    'Unexpected text format when upgrading numerical questions.');
     }
 }
diff --git a/question/type/numerical/edit_numerical_form.php b/question/type/numerical/edit_numerical_form.php
index 633863345c0..17f32dcc1f8 100644
--- a/question/type/numerical/edit_numerical_form.php
+++ b/question/type/numerical/edit_numerical_form.php
@@ -243,7 +243,7 @@ class qtype_numerical_edit_form extends question_edit_form {
      * @param array $errors the errors array to add to.
      * @return array the updated errors array.
      */
-    function validate_answers($data, $errors) {
+    protected function validate_answers($data, $errors) {
         // Check the answers.
         $answercount = 0;
         $maxgrade = false;
@@ -282,14 +282,14 @@ class qtype_numerical_edit_form extends question_edit_form {
      * @param array $data the submitted data.
      * @return bool whether this is a valid answer.
      */
-    function is_valid_answer($answer, $data) {
+    protected function is_valid_answer($answer, $data) {
         return $answer == '*' || is_numeric($answer);
     }
 
     /**
      * @return string erre describing what an answer should be.
      */
-    function valid_answer_message($answer) {
+    protected function valid_answer_message($answer) {
         return get_string('answermustbenumberorstar', 'qtype_numerical');
     }
 
@@ -299,7 +299,7 @@ class qtype_numerical_edit_form extends question_edit_form {
      * @param array $errors the errors array to add to.
      * @return array the updated errors array.
      */
-    function validate_numerical_options($data, $errors) {
+    protected function validate_numerical_options($data, $errors) {
         if ($data['unitrole'] != qtype_numerical::UNITNONE && trim($data['unit'][0]) == '') {
             $errors['unit[0]'] = get_string('unitonerequired', 'qtype_numerical');
         }
diff --git a/question/type/numerical/question.php b/question/type/numerical/question.php
index b2d59583603..2300c6cd3d9 100644
--- a/question/type/numerical/question.php
+++ b/question/type/numerical/question.php
@@ -49,10 +49,6 @@ class qtype_numerical_question extends question_graded_automatically {
     /** @var qtype_numerical_answer_processor */
     public $ap;
 
-    public function __construct() {
-        parent::__construct();
-    }
-
     public function get_expected_data() {
         $expected = array('answer' => PARAM_RAW_TRIMMED);
         if ($this->unitdisplay == qtype_numerical::UNITSELECT) {
@@ -244,7 +240,7 @@ class qtype_numerical_question extends question_graded_automatically {
                 $this->apply_unit_penalty($ans->fraction, $unit)));
     }
 
-    function check_file_access($question, $state, $options, $contextid, $component,
+    public function check_file_access($question, $state, $options, $contextid, $component,
             $filearea, $args) {
         if ($component == 'question' && $filearea == 'answerfeedback') {
             $currentanswer = $qa->get_last_qt_var('answer');
@@ -256,7 +252,8 @@ class qtype_numerical_question extends question_graded_automatically {
             return $this->check_hint_file_access($qa, $options, $args);
 
         } else {
-            return parent::check_file_access($qa, $options, $component, $filearea, $args, $forcedownload);
+            return parent::check_file_access($qa, $options, $component, $filearea,
+                    $args, $forcedownload);
         }
     }
 }
diff --git a/question/type/numerical/questiontype.php b/question/type/numerical/questiontype.php
index fdf5ded9ac1..2852c3d5af2 100644
--- a/question/type/numerical/questiontype.php
+++ b/question/type/numerical/questiontype.php
@@ -27,8 +27,6 @@
 
 defined('MOODLE_INTERNAL') || die();
 
-//require_once($CFG->dirroot . '/question/type/numerical/question.php');
-
 
 /**
  * The numerical question type class.
@@ -130,7 +128,7 @@ class qtype_numerical extends question_type {
             if ($defaultunit = $this->get_default_numerical_unit($question)) {
                 $question->options->showunits = self::UNITINPUT;
             } else {
-                $question->options->showunits = self::UNITNONE ;
+                $question->options->showunits = self::UNITNONE;
             }
             $question->options->unitsleft = 0;
 
@@ -248,12 +246,13 @@ class qtype_numerical extends question_type {
      * as old question.
      *
      */
-    function save_unit_options($question) {
+    public function save_unit_options($question) {
         global $DB;
         $result = new stdClass();
 
-        $update = true ;
-        $options = $DB->get_record('question_numerical_options', array('question' => $question->id));
+        $update = true;
+        $options = $DB->get_record('question_numerical_options',
+                array('question' => $question->id));
         if (!$options) {
             $options = new stdClass();
             $options->question = $question->id;
@@ -264,7 +263,7 @@ class qtype_numerical extends question_type {
             $options->unitpenalty = $question->unitpenalty;
         } else {
             // Either an old question or a close question type.
-            $options->unitpenalty = 1 ;
+            $options->unitpenalty = 1;
         }
 
         $options->unitgradingtype = 0;
@@ -370,7 +369,7 @@ class qtype_numerical extends question_type {
         return new qtype_numerical_answer_processor($cleanedunits, $unitsleft);
     }
 
-    function delete_question($questionid, $contextid) {
+    public function delete_question($questionid, $contextid) {
         global $DB;
         $DB->delete_records('question_numerical', array('question' => $questionid));
         $DB->delete_records('question_numerical_options', array('question' => $questionid));
@@ -379,202 +378,6 @@ class qtype_numerical extends question_type {
         parent::delete_question($questionid, $contextid);
     }
 
-    /**
-    * This function has been reinserted in numerical/questiontype.php to simplify
-    * the separate rendering of number and unit
-    */
-    function print_question_formulation_and_controls(&$question, &$state, $cmoptions, $options) {
-        global $CFG, $OUTPUT;
-
-        $context = $this->get_context_by_category_id($question->category);
-        $readonly = empty($options->readonly) ? '' : 'readonly="readonly"';
-        $formatoptions = new stdClass();
-        $formatoptions->noclean = true;
-        $formatoptions->para = false;
-        $nameprefix = $question->name_prefix;
-        /// Print question text and media
-
-        $questiontext = format_text($question->questiontext,
-                $question->questiontextformat, $formatoptions, $cmoptions->course);
-
-        /// Print input controls
-        // as the entry is controlled the question type here is numerical
-        // In all cases there is a text input for the number
-        // If $question->options->showunits == NUMERICALQUESTIONUNITTEXTDISPLAY
-        // there is an additional text input for the unit
-        // If $question->options->showunits == NUMERICALQUESTIONUNITMULTICHOICEDISPLAY"
-        // radio elements display the defined unit
-        // The code allows the input number elememt to be displayed
-        // before i.e. at left or after at rigth of the unit variants.
-        $nameanswer = "name=\"".$question->name_prefix."answer\"";
-        $nameunit   = "name=\"".$question->name_prefix."unit\"";
-        // put old answer data in $state->responses['answer'] and $state->responses['unit']
-        if (isset($state->responses['']) && $state->responses[''] != '' && !isset($state->responses['answer'])) {
-              $this->split_old_answer($state->responses[''], $question->options->units, $state->responses['answer'] ,$state->responses['unit'] );
-        }
-        // prepare the values of the input elements to be dispalyed answer i.e. number  and unit
-        if (isset($state->responses['answer']) && $state->responses['answer']!='') {
-            $valueanswer = ' value="'.s($state->responses['answer']).'" ';
-        } else {
-            $valueanswer = ' value="" ';
-        }
-        if (isset($state->responses['unit']) && $state->responses['unit']!='') {
-            $valueunit = ' value="'.s($state->responses['unit']).'" ';
-        } else {
-            $valueunit = ' value="" ';
-            if ($question->options->showunits == NUMERICALQUESTIONUNITTEXTDISPLAY ) {
-              $valueunit = ' value="'.s($question->options->units[0]->unit).'" ';
-            }
-        }
-
-        $feedback = '';
-        $class = '';
-        $classunit = '' ;
-        $classunitvalue = '' ;
-        $feedbackimg = '';
-        $feedbackimgunit = '' ;
-        $answerasterisk = false ;
-        $response = '' ;
-        $valid_numerical_unit = false ;
-        $valid_numerical_unit_index = -1 ;
-        $unit_in_numerical_answer = false ;
-        $rawgrade = 0 ;
-        if ($options->feedback) {
-            $class = question_get_feedback_class(0);
-            $classunit = question_get_feedback_class(0);
-            $feedbackimg = question_get_feedback_image(0);
-            $feedbackimgunit = question_get_feedback_image(0);
-            $classunitvalue = 0 ;
-            $valid_numerical_unit_index = -1 ;
-            // if there is unit in answer and unitgradingtype = 0
-            // the grade is 0
-            //this is OK for the first answer with a good response
-            // having to test for * so response as long as not empty
-           // $response = $this->extract_numerical_response($state->responses['answer']);
-            // test for a greater than 0 grade
-            foreach($question->options->answers as $answer) {
-                if ($this->test_response($question, $state, $answer)) {
-                    // Answer was correct or partially correct.
-                    if ( $answer->answer === '*') {
-                        $answerasterisk = true ;
-                    }
-                    // in all cases
-                    $class = question_get_feedback_class($answer->fraction);
-                    $feedbackimg = question_get_feedback_image($answer->fraction);
-                    if ($question->options->unitgradingtype == 0 || ($question->options->unitgradingtype == 0 && $answer->answer === '*')) {
-                        // if * then unit has the $answer->fraction value
-                        // if $question->options->unitgradingtype == 0 everything has been checked
-                        // if $question->options->showunits == NUMERICALQUESTIONUNITTEXTINPUTDISPLAY
-                        // then number - unit combination has been used to test response
-                        // so the unit should have same color
-                        $classunit = question_get_feedback_class($answer->fraction);
-                        $feedbackimgunit = question_get_feedback_image($answer->fraction);
-                        $rawgrade = $answer->fraction ;
-
-
-                    }else {
-                        /* so we need to apply unit grading i.e. to check if the number-unit combination
-                        * was the rigth one
-                        * on NUMERICALQUESTIONUNITTEXTINPUTDISPLAY we need only to ckeck if applyunit will test OK
-                        * with the $state->responses['unit'] value which cannot be empty
-                        * if $state->responses['unit']
-                        * if apply-unit is true with a specific unit as long as the unit as been written either in the
-                        * we need the numerical response and test it with the available units
-                        * if the unit used is good then it should be set OK
-                        * however the unit could have been put in the number element in this case
-                        * the unit penalty should be apllied.
-                        * testing apply_unit with no units will get us a false response if there is any text in it
-                        * testing apply_unit with a given unit will get a good value if the number is good with this unit
-                        * apply unit will return the numerical if
-                        * we need to know which conditions let to a good numerical value that were done in the
-                        */
-                        $valid_numerical_unit = false ;
-                        $rawgrade = $answer->fraction ;
-                        $valid_numerical_unit_index = -1 ;
-                        $invalid_unit_in_numerical_answer = false ;
-                        if ( $answerasterisk ) {
-                            $classunit = question_get_feedback_class($answer->fraction);
-                            $feedbackimgunit = question_get_feedback_image($answer->fraction);
-                            $valid_numerical_unit = true ;//everything is true with *
-                        } else {
-                          //  if( isset($state->responses['unit']) && $state->responses['unit'] != '' ) {// unit should be written in the unit input or checked in multichoice
-                            // we need to see if something was written in the answer field that was not in the number
-                            // although we cannot actually detect units put before the number which will cause bad numerical.
-                            // use extract response
-                            $response = $this->extract_numerical_response($state->responses['answer']);
-                            if(isset($response->unit ) && $response->unit != '') {
-                                $unit_in_numerical_answer = true ;
-                            }else {
-                                $unit_in_numerical_answer = false ;
-                            }
-
-                            // the we let the testing to the two cases either
-                            // NUMERICALQUESTIONUNITTEXTINPUTDISPLAY or
-                            // NUMERICALQUESTIONUNITMULTICHOICEDISPLAY
-                            if( !isset($state->responses['unit']) || $state->responses['unit'] == '' ) {
-                                // unit should be written in the unit input or checked in multichoice
-                                $valid_numerical_unit = false ;
-                                $classunit = question_get_feedback_class(0);
-                                $feedbackimgunit = question_get_feedback_image(0);
-                                $empty_unit = true ;
-                            } else {
-                               // echo"<p> some unit answer <pre>";print_r($answer) ;echo"</pre></p>";
-                               // echo"<p> some unit answer <pre>";print_r($answer) ;echo"</pre></p>";
-                                $empty_unit = false ;
-                                $valid_numerical_unit = false ;
-
-                                foreach ($question->options->units as $key => $unit) {
-                                    if ($unit->unit == $state->responses['unit']) {
-                                    //    $response = $this->apply_unit($state->responses['answer'].$unit->unit, array($question->options->units[$key])) ;
-                                //       echo "<p> avant false valid_numerical_unit_index $valid_numerical_unit_index  ".$state->responses['answer']."</p>";
-                                        $invalid_unit_found = 0 ;
-                                        if ($response->number !== false) {
-                                //echo "<p> avanr get valid_numerical_unit_index $valid_numerical_unit_index  </p>";
-                                       //     $this->get_tolerance_interval($answer);
-                                       $testresponse = $response->number /$unit->multiplier ;
-                                            if($answer->min <= $testresponse && $testresponse <= $answer->max) {
-                                //echo "<p> apres min max  valid_numerical_unit_index $valid_numerical_unit_index  </p>";
-                                                $classunit = question_get_feedback_class($answer->fraction) ; //question_get_feedback_class(1);
-                                                $feedbackimgunit = question_get_feedback_image($rawgrade);
-                                                $valid_numerical_unit = true ;
-                                                $valid_numerical_unit_index = $key ;
-                                                break ;
-                                            }
-                                        }
-                                    }
-                                }
-                            }
-                        }
-                    }
-                    if ($answer->feedback) {
-                        $answer->feedback = quiz_rewrite_question_urls($answer->feedback, 'pluginfile.php', $context->id, 'question', 'answerfeedback', array($state->attempt, $state->question), $answer->id);
-                        $feedback = format_text($answer->feedback, $answer->feedbackformat, $formatoptions, $cmoptions->course);
-                    }
-
-                    break;
-                }
-            }
-    }
-        $state->options->raw_unitpenalty = 0 ;
-        $raw_unitpenalty = 0 ;
-        if( $question->options->showunits == NUMERICALQUESTIONUNITNODISPLAY ||
-                $question->options->showunits == NUMERICALQUESTIONUNITTEXTDISPLAY ) {
-                    $classunitvalue = 1 ;
-        }
-
-        if(! $answerasterisk  && $question->options->unitgradingtype != 0 && (! $valid_numerical_unit || $unit_in_numerical_answer)) {
-            if($question->options->unitgradingtype == 1) {
-                $raw_unitpenalty = $question->options->unitpenalty * $rawgrade ;
-            }else {
-                $raw_unitpenalty = $question->options->unitpenalty ;
-            }
-            $state->options->raw_unitpenalty = $raw_unitpenalty ;
-        }
-
-        /// Removed correct answer, to be displayed later MDL-7496
-        include("$CFG->dirroot/question/type/numerical/display.html");
-    }
-
     public function get_random_guess_score($questiondata) {
         foreach ($questiondata->options->answers as $aid => $answer) {
             if ('*' == trim($answer->answer)) {
@@ -641,13 +444,13 @@ class qtype_numerical extends question_type {
      * @return float               The rawresponse with the unit taken into
      *                             account as a float.
      */
-    function apply_unit($rawresponse, $units, $unitsleft) {
+    public function apply_unit($rawresponse, $units, $unitsleft) {
         $ap = $this->make_answer_processor($units, $unitsleft);
         list($value, $unit) = $ap->apply_units($rawresponse);
         return $value;
     }
 
-    function move_files($questionid, $oldcontextid, $newcontextid) {
+    public function move_files($questionid, $oldcontextid, $newcontextid) {
         $fs = get_file_storage();
 
         parent::move_files($questionid, $oldcontextid, $newcontextid);
@@ -681,7 +484,8 @@ class qtype_numerical_answer_processor {
 
     protected $regex = null;
 
-    public function __construct($units, $unitsbefore = false, $decsep = null, $thousandssep = null) {
+    public function __construct($units, $unitsbefore = false, $decsep = null,
+            $thousandssep = null) {
         if (is_null($decsep)) {
             $decsep = get_string('decsep', 'langconfig');
         }
diff --git a/question/type/numerical/simpletest/helper.php b/question/type/numerical/simpletest/helper.php
index bb1554448f3..fa463defd6c 100644
--- a/question/type/numerical/simpletest/helper.php
+++ b/question/type/numerical/simpletest/helper.php
@@ -51,11 +51,16 @@ class qtype_numerical_test_helper extends question_test_helper {
         $num->questiontext = 'What is pi to two d.p.?';
         $num->generalfeedback = 'Generalfeedback: 3.14 is the right answer.';
         $num->answers = array(
-            13 => new qtype_numerical_answer(13, '3.14', 1.0, 'Very good.', FORMAT_HTML, 0),
-            14 => new qtype_numerical_answer(14, '3.142', 0.0, 'Too accurate.', FORMAT_HTML, 0.005),
-            15 => new qtype_numerical_answer(15, '3.1', 0.0, 'Not accurate enough.', FORMAT_HTML, 0.05),
-            16 => new qtype_numerical_answer(16, '3', 0.0, 'Not accurate enough.', FORMAT_HTML, 0.5),
-            17 => new qtype_numerical_answer(17, '*', 0.0, 'Completely wrong.', FORMAT_HTML, 0),
+            13 => new qtype_numerical_answer(13, '3.14',  1.0, 'Very good.',
+                    FORMAT_HTML, 0),
+            14 => new qtype_numerical_answer(14, '3.142', 0.0, 'Too accurate.',
+                    FORMAT_HTML, 0.005),
+            15 => new qtype_numerical_answer(15, '3.1',   0.0, 'Not accurate enough.',
+                    FORMAT_HTML, 0.05),
+            16 => new qtype_numerical_answer(16, '3',     0.0, 'Not accurate enough.',
+                    FORMAT_HTML, 0.5),
+            17 => new qtype_numerical_answer(17, '*',     0.0, 'Completely wrong.',
+                    FORMAT_HTML, 0),
         );
         $num->qtype = question_bank::get_qtype('numerical');
         $num->unitdisplay = qtype_numerical::UNITOPTIONAL;
diff --git a/question/type/numerical/simpletest/testanswerprocessor.php b/question/type/numerical/simpletest/testanswerprocessor.php
index cb43fab4dce..40e988aeb56 100644
--- a/question/type/numerical/simpletest/testanswerprocessor.php
+++ b/question/type/numerical/simpletest/testanswerprocessor.php
@@ -95,7 +95,8 @@ class qtype_numerical_answer_processor_test extends UnitTestCase {
 
     public function test_apply_units() {
         $ap = new qtype_numerical_answer_processor(
-                array('m/s' => 1, 'c' => 3.3356409519815E-9, 'mph' => 2.2369362920544), false, '.', ',');
+                array('m/s' => 1, 'c' => 3.3356409519815E-9,
+                        'mph' => 2.2369362920544), false, '.', ',');
 
         $this->verify_value_and_unit(3e8, 'm/s', $ap, '3x10^8 m/s');
         $this->verify_value_and_unit(3e8, '', $ap, '3x10^8');
@@ -108,7 +109,8 @@ class qtype_numerical_answer_processor_test extends UnitTestCase {
 
     public function test_apply_units_separate_unit() {
         $ap = new qtype_numerical_answer_processor(
-                array('m/s' => 1, 'c' => 3.3356409519815E-9, 'mph' => 2.2369362920544), false, '.', ',');
+                array('m/s' => 1, 'c' => 3.3356409519815E-9,
+                        'mph' => 2.2369362920544), false, '.', ',');
 
         $this->verify_value_and_unit(3e8, 'm/s', $ap, '3x10^8', 'm/s');
         $this->verify_value_and_unit(3e8, '', $ap, '3x10^8', '');
diff --git a/question/type/random/db/simpletest/testupgradelibnewqe.php b/question/type/random/db/simpletest/testupgradelibnewqe.php
index d580b7f6e26..4986c17c80c 100644
--- a/question/type/random/db/simpletest/testupgradelibnewqe.php
+++ b/question/type/random/db/simpletest/testupgradelibnewqe.php
@@ -670,7 +670,7 @@ class qtype_random_attempt_upgrader_test extends question_attempt_upgrader_test_
             'timecreated' => '1262959197',
             'timemodified' => '0',
             'createdby' => '123783',
-            'modifiedby' => NULL,
+            'modifiedby' => null,
             'unlimited' => '0',
             'options' => (object) array(
                 'answers' => array(
@@ -726,13 +726,13 @@ class qtype_random_attempt_upgrader_test extends question_attempt_upgrader_test_
                 44315 => (object) array(
                         'questionid' => '83248',
                         'hint' => 'See Unit 2, Subsection 2.3.',
-                        'rest' => NULL,
+                        'rest' => null,
                         'id' => 44315,
                 ),
                 44316 => (object) array(
                         'questionid' => '83248',
                         'hint' => '<p> Find the measurement on the horizontal axis, draw a line vertically up to meet the conversion line and read off the corresponding value on the vertical axis. </p><p>See Unit 2, Subsection 2.3. </p>',
-                        'rest' => NULL,
+                        'rest' => null,
                         'id' => 44316,
                 ),
             ),
diff --git a/question/type/shortanswer/db/simpletest/testupgradelibnewqe.php b/question/type/shortanswer/db/simpletest/testupgradelibnewqe.php
index 07805b3382d..c327bd8f4b9 100644
--- a/question/type/shortanswer/db/simpletest/testupgradelibnewqe.php
+++ b/question/type/shortanswer/db/simpletest/testupgradelibnewqe.php
@@ -105,9 +105,9 @@ class qtype_shortanswer_attempt_upgrader_test extends question_attempt_upgrader_
             'generalfeedbackformat' => '1',
             'timecreated' => '0',
             'timemodified' => '0',
-            'createdby' => NULL,
-            'modifiedby' => NULL,
-            'unlimited' => NULL,
+            'createdby' => null,
+            'modifiedby' => null,
+            'unlimited' => null,
             'maxmark' => '1',
             'options' => (object) array(
                 'answers' => array(
@@ -313,9 +313,9 @@ class qtype_shortanswer_attempt_upgrader_test extends question_attempt_upgrader_
             'generalfeedbackformat' => '1',
             'timecreated' => '0',
             'timemodified' => '0',
-            'createdby' => NULL,
-            'modifiedby' => NULL,
-            'unlimited' => NULL,
+            'createdby' => null,
+            'modifiedby' => null,
+            'unlimited' => null,
             'maxmark' => '1',
             'options' => (object) array(
                 'answers' => array(
@@ -486,9 +486,9 @@ class qtype_shortanswer_attempt_upgrader_test extends question_attempt_upgrader_
             'generalfeedbackformat' => '1',
             'timecreated' => '0',
             'timemodified' => '0',
-            'createdby' => NULL,
-            'modifiedby' => NULL,
-            'unlimited' => NULL,
+            'createdby' => null,
+            'modifiedby' => null,
+            'unlimited' => null,
             'maxmark' => '1',
             'options' => (object) array(
                 'answers' => array(
diff --git a/question/type/truefalse/db/simpletest/testupgradelibnewqe.php b/question/type/truefalse/db/simpletest/testupgradelibnewqe.php
index 6b64bbcd483..e62e89be85e 100644
--- a/question/type/truefalse/db/simpletest/testupgradelibnewqe.php
+++ b/question/type/truefalse/db/simpletest/testupgradelibnewqe.php
@@ -103,9 +103,9 @@ class qtype_truefalse_attempt_upgrader_test extends question_attempt_upgrader_te
             'generalfeedbackformat' => '1',
             'timecreated' => '0',
             'timemodified' => '0',
-            'createdby' => NULL,
-            'modifiedby' => NULL,
-            'unlimited' => NULL,
+            'createdby' => null,
+            'modifiedby' => null,
+            'unlimited' => null,
             'maxmark' => '5',
             'options' => (object) array(
                 'id' => '98',
@@ -302,7 +302,7 @@ class qtype_truefalse_attempt_upgrader_test extends question_attempt_upgrader_te
             'generalfeedbackformat' => '1',
             'timecreated' => '0',
             'timemodified' => '1204646598',
-            'createdby' => NULL,
+            'createdby' => null,
             'modifiedby' => '97230',
             'unlimited' => '0',
             'maxmark' => '1',
@@ -470,9 +470,9 @@ class qtype_truefalse_attempt_upgrader_test extends question_attempt_upgrader_te
             'generalfeedbackformat' => '1',
             'timecreated' => '0',
             'timemodified' => '0',
-            'createdby' => NULL,
-            'modifiedby' => NULL,
-            'unlimited' => NULL,
+            'createdby' => null,
+            'modifiedby' => null,
+            'unlimited' => null,
             'maxmark' => '1',
             'options' => (object) array(
                 'id' => '24',