From b46badb1308c862ecf99a48c4cbf1cbe585fbebf Mon Sep 17 00:00:00 2001
From: Marina Glancy <marina@moodle.com>
Date: Wed, 17 Feb 2021 12:41:12 +0100
Subject: [PATCH] MDL-70926 core: getuserdate() shoud show debugging if null
 was passed

passing null to getdate() has different results in PHP7 and PHP8
---
 .../local/event/factories/event_abstract_factory.php      | 2 +-
 calendar/tests/helpers.php                                | 2 +-
 lib/excellib.class.php                                    | 2 +-
 lib/form/defaultcustom.php                                | 2 +-
 lib/moodlelib.php                                         | 8 ++++++++
 lib/tests/moodlelib_test.php                              | 6 ++++++
 6 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/calendar/classes/local/event/factories/event_abstract_factory.php b/calendar/classes/local/event/factories/event_abstract_factory.php
index b964673cf35..dccd2dc831b 100644
--- a/calendar/classes/local/event/factories/event_abstract_factory.php
+++ b/calendar/classes/local/event/factories/event_abstract_factory.php
@@ -192,7 +192,7 @@ abstract class event_abstract_factory implements event_factory_interface {
                 (new \DateTimeImmutable())->setTimestamp($dbrow->timestart + $dbrow->timeduration),
                 (new \DateTimeImmutable())->setTimestamp($dbrow->timesort ? $dbrow->timesort : $dbrow->timestart),
                 (new \DateTimeImmutable())->setTimestamp($dbrow->timemodified),
-                (new \DateTimeImmutable())->setTimestamp(usergetmidnight($dbrow->timesort))
+                (new \DateTimeImmutable())->setTimestamp($dbrow->timesort ? usergetmidnight($dbrow->timesort) : 0)
             ),
             !empty($dbrow->visible),
             $subscription,
diff --git a/calendar/tests/helpers.php b/calendar/tests/helpers.php
index 5c373dc0a2e..46eaff79f01 100644
--- a/calendar/tests/helpers.php
+++ b/calendar/tests/helpers.php
@@ -230,7 +230,7 @@ class action_event_test_factory implements event_factory_interface {
                 (new \DateTimeImmutable())->setTimestamp($record->timestart + $record->timeduration),
                 (new \DateTimeImmutable())->setTimestamp($record->timesort ? $record->timesort : $record->timestart),
                 (new \DateTimeImmutable())->setTimestamp($record->timemodified),
-                (new \DateTimeImmutable())->setTimestamp(usergetmidnight($record->timesort))
+                (new \DateTimeImmutable())->setTimestamp($record->timesort ? usergetmidnight($record->timesort) : 0)
             ),
             !empty($record->visible),
             $subscription,
diff --git a/lib/excellib.class.php b/lib/excellib.class.php
index 2bd4a0f8eed..6950fbbdc44 100644
--- a/lib/excellib.class.php
+++ b/lib/excellib.class.php
@@ -246,7 +246,7 @@ class MoodleExcelWorksheet {
      * Write one date somewhere in the worksheet.
      * @param integer $row    Zero indexed row
      * @param integer $col    Zero indexed column
-     * @param string  $date   The date to write in UNIX timestamp format
+     * @param int     $date   The date to write in UNIX timestamp format
      * @param mixed   $format The XF format for the cell
      */
     public function write_date($row, $col, $date, $format = null) {
diff --git a/lib/form/defaultcustom.php b/lib/form/defaultcustom.php
index 16a263d1399..300f2d837bb 100644
--- a/lib/form/defaultcustom.php
+++ b/lib/form/defaultcustom.php
@@ -103,7 +103,7 @@ class MoodleQuickForm_defaultcustom extends MoodleQuickForm_group {
      */
     protected function timestamp_to_date_array($value) {
         $calendartype = \core_calendar\type_factory::get_calendar_instance();
-        $currentdate = $calendartype->timestamp_to_date_array($value, $this->_options['timezone']);
+        $currentdate = $calendartype->timestamp_to_date_array((int)$value, $this->_options['timezone']);
         return array(
             'minute' => $currentdate['minutes'],
             'hour' => $currentdate['hours'],
diff --git a/lib/moodlelib.php b/lib/moodlelib.php
index b6e9e2f2e63..bfbfaaedea4 100644
--- a/lib/moodlelib.php
+++ b/lib/moodlelib.php
@@ -2354,6 +2354,14 @@ function date_format_string($date, $format, $tz = 99) {
  * @return array An array that represents the date in user time
  */
 function usergetdate($time, $timezone=99) {
+    if ($time === null) {
+        // PHP8 and PHP7 return different results when getdate(null) is called.
+        // Display warning and cast to 0 to make sure the usergetdate() behaves consistently on all versions of PHP.
+        // In the future versions of Moodle we may consider adding a strict typehint.
+        debugging('usergetdate() expects parameter $time to be int, null given', DEBUG_DEVELOPER);
+        $time = 0;
+    }
+
     date_default_timezone_set(core_date::get_user_timezone($timezone));
     $result = getdate($time);
     core_date::set_default_server_timezone();
diff --git a/lib/tests/moodlelib_test.php b/lib/tests/moodlelib_test.php
index 34f2f1c0a7d..4357f5a2825 100644
--- a/lib/tests/moodlelib_test.php
+++ b/lib/tests/moodlelib_test.php
@@ -1317,6 +1317,12 @@ class core_moodlelib_testcase extends advanced_testcase {
         $this->assertSame(356, $yday);
         $this->assertSame('Wednesday', $weekday);
         $this->assertSame('December', $month);
+
+        // Edge cases - 0 and null - they all mean 1st Jan 1970. Null shows debugging message.
+        $this->assertSame(1970, usergetdate(0)['year']);
+        $this->assertDebuggingNotCalled();
+        $this->assertSame(1970, usergetdate(null)['year']);
+        $this->assertDebuggingCalled(null, DEBUG_DEVELOPER);
     }
 
     public function test_mark_user_preferences_changed() {