From 20482f9d41ac20bcc9dd9be31cfcadf4bb6ed688 Mon Sep 17 00:00:00 2001
From: Tim Hunt <T.J.Hunt@open.ac.uk>
Date: Mon, 25 Jun 2018 15:05:33 +0100
Subject: [PATCH 1/2] MDL-62792 filter_mathjaxloader: don't use statics for
 once-only items

---
 filter/mathjaxloader/filter.php | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/filter/mathjaxloader/filter.php b/filter/mathjaxloader/filter.php
index a6010bfbcad..50e568e45d2 100644
--- a/filter/mathjaxloader/filter.php
+++ b/filter/mathjaxloader/filter.php
@@ -79,10 +79,8 @@ class filter_mathjaxloader extends moodle_text_filter {
      * @param context $context The current context.
      */
     public function setup($page, $context) {
-        // This only requires execution once per request.
-        static $jsinitialised = false;
 
-        if (empty($jsinitialised)) {
+        if ($page->requires->should_create_one_time_item_now('filter_mathjaxloader-scripts')) {
             $url = get_config('filter_mathjaxloader', 'httpsurl');
             $lang = $this->map_language_code(current_language());
             $url = new moodle_url($url, array('delayStartupUntil' => 'configured'));
@@ -102,8 +100,6 @@ class filter_mathjaxloader extends moodle_text_filter {
             $params = array('mathjaxconfig' => $config, 'lang' => $lang);
 
             $page->requires->yui_module('moodle-filter_mathjaxloader-loader', 'M.filter_mathjaxloader.configure', array($params));
-
-            $jsinitialised = true;
         }
     }
 

From 9f38628abc23e76f06a76f9f8e44655545c65669 Mon Sep 17 00:00:00 2001
From: Tim Hunt <T.J.Hunt@open.ac.uk>
Date: Mon, 25 Jun 2018 15:16:23 +0100
Subject: [PATCH 2/2] MDL-62792 filters: fix some bad PHPdocs

---
 lib/filterlib.php | 34 +++++++++++++++++++++++++++-------
 1 file changed, 27 insertions(+), 7 deletions(-)

diff --git a/lib/filterlib.php b/lib/filterlib.php
index 0a9753ba4f6..693922cd25f 100644
--- a/lib/filterlib.php
+++ b/lib/filterlib.php
@@ -302,15 +302,36 @@ class filter_manager {
  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 class null_filter_manager {
+    /**
+     * As for the equivalent {@link filter_manager} method.
+     *
+     * @param string $text The text to filter
+     * @param context $context not used.
+     * @param array $options not used
+     * @param array $skipfilters not used
+     * @return string resulting text.
+     */
     public function filter_text($text, $context, array $options = array(),
             array $skipfilters = null) {
         return $text;
     }
 
+    /**
+     * As for the equivalent {@link filter_manager} method.
+     *
+     * @param string $string The text to filter
+     * @param context $context not used.
+     * @return string resulting string
+     */
     public function filter_string($string, $context) {
         return $string;
     }
 
+    /**
+     * As for the equivalent {@link filter_manager} method.
+     *
+     * @deprecated Since Moodle 3.0 MDL-50491.
+     */
     public function text_filtering_hash() {
         throw new coding_exception('filter_manager::text_filtering_hash() can not be used any more');
     }
@@ -429,9 +450,9 @@ abstract class moodle_text_filter {
     /**
      * Override this function to actually implement the filtering.
      *
-     * @param $text some HTML content.
+     * @param string $text some HTML content to process.
      * @param array $options options passed to the filters
-     * @return the HTML content after the filtering has been applied.
+     * @return string the HTML content after the filtering has been applied.
      */
     public abstract function filter($text, array $options = array());
 }
@@ -520,8 +541,6 @@ function filter_get_name($filter) {
  * sorted in alphabetical order of name.
  */
 function filter_get_all_installed() {
-    global $CFG;
-
     $filternames = array();
     foreach (core_component::get_plugin_list('filter') as $filter => $fulldir) {
         if (is_readable("$fulldir/filter.php")) {
@@ -1428,9 +1447,10 @@ function filter_phrases($text, &$link_array, $ignoretagsopen=NULL, $ignoretagscl
 }
 
 /**
- * @todo Document this function
- * @param array $linkarray
- * @return array
+ * Remove duplicate from a list of {@link filterobject}.
+ *
+ * @param filterobject[] $linkarray a list of filterobject.
+ * @return filterobject[] the same list, but with dupicates removed.
  */
 function filter_remove_duplicates($linkarray) {