From ce46c290e89a6f5d909830e23a54df297832fd4f Mon Sep 17 00:00:00 2001
From: Angel Fernando Quiroz Campos <angelfqc.18@gmail.com>
Date: Mon, 19 Oct 2015 16:53:56 -0500
Subject: [PATCH] Fix fatal error by use method return value in write context -
 refs #7907

---
 plugin/buycourses/src/buy_course_plugin.class.php | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/plugin/buycourses/src/buy_course_plugin.class.php b/plugin/buycourses/src/buy_course_plugin.class.php
index 1bafd0cb3f..10fae52ffa 100644
--- a/plugin/buycourses/src/buy_course_plugin.class.php
+++ b/plugin/buycourses/src/buy_course_plugin.class.php
@@ -1164,13 +1164,17 @@ class BuyCoursesPlugin extends Plugin
             'price' => 0.00
         ];
 
-        if (!empty($session->getDisplayStartDate())) {
+        $displayStartDate = $session->getDisplayStartDate();
+
+        if (!empty($displayStartDate)) {
             $sessionItem['session_display_start_date'] = api_format_date(
                 $session->getDisplayStartDate()->format('Y-m-d h:i:s')
             );
         }
 
-        if (!empty($session->getDisplayEndDate())) {
+        $displayEndDate = $session->getDisplayEndDate();
+
+        if (!empty($displayEndDate)) {
             $sessionItem['session_display_end_date'] = api_format_date(
                 $session->getDisplayEndDate()->format('Y-m-d h:i:s'),
                 DATE_TIME_FORMAT_LONG_24H