From c28eb52862ee8d4cb75fde970b2d21081b169ec1 Mon Sep 17 00:00:00 2001
From: Gedion Woldeselassie <wolde034@x-134-84-3-175.vpn.umn.edu>
Date: Tue, 21 Jul 2015 14:24:16 -0500
Subject: [PATCH] MDL-50894 lib/conditionlib: Occasional cron error

Inhibit division by zero error warnings when rawgrademax and rawgrademin are
equal. The change does not affect existing functional behavior.
---
 availability/condition/grade/classes/condition.php | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/availability/condition/grade/classes/condition.php b/availability/condition/grade/classes/condition.php
index 8a4bd5bb996..440683cb05b 100644
--- a/availability/condition/grade/classes/condition.php
+++ b/availability/condition/grade/classes/condition.php
@@ -228,7 +228,9 @@ class condition extends \core_availability\condition {
                         WHERE
                             gi.courseid = ?', array($userid, $courseid));
                 foreach ($rs as $record) {
-                    if (is_null($record->finalgrade)) {
+                    // This function produces division by zero error warnings when rawgrademax and rawgrademin
+                    // are equal. Below change does not affect function behavior, just avoids the warning.
+                    if (is_null($record->finalgrade) || $record->rawgrademax == $record->rawgrademin) {
                         // No grade = false.
                         $cachedgrades[$record->id] = false;
                     } else {
@@ -249,7 +251,9 @@ class condition extends \core_availability\condition {
                 // Just get current grade.
                 $record = $DB->get_record('grade_grades', array(
                     'userid' => $userid, 'itemid' => $gradeitemid));
-                if ($record && !is_null($record->finalgrade)) {
+                // This function produces division by zero error warnings when rawgrademax and rawgrademin
+                // are equal. Below change does not affect function behavior, just avoids the warning.
+                if ($record && !is_null($record->finalgrade) && $record->rawgrademax != $record->rawgrademin) {
                     $score = (($record->finalgrade - $record->rawgrademin) * 100) /
                         ($record->rawgrademax - $record->rawgrademin);
                 } else {