Fixed GH-10447: 'p' format specifier does not yield 'Z' for 00:00

Author: derickr

ext/date/php_date.c

@@ -716,7 +716,7 @@ static zend_string *date_format(const char *format, size_t format_len, timelib_t
 			/* timezone */
 			case 'I': length = slprintf(buffer, sizeof(buffer), "%d", localtime ? offset->is_dst : 0); break;
 			case 'p':
-				if (!localtime || strcmp(offset->abbr, "UTC") == 0 || strcmp(offset->abbr, "Z") == 0) {
+				if (!localtime || strcmp(offset->abbr, "UTC") == 0 || strcmp(offset->abbr, "Z") == 0 || strcmp(offset->abbr, "GMT+0000") == 0) {
 					length = slprintf(buffer, sizeof(buffer), "%s", "Z");
 					break;
 				}

ext/date/tests/gh10447.phpt

@@ -0,0 +1,13 @@
+--TEST--
+Bug GH-10447 ('p' format specifier does not yield 'Z' for 00:00)
+--FILE--
+<?php
+$date = new \DateTimeImmutable('2023-01-25T00:00:00+00:00');
+echo $date->format('Y-m-d\TH:i:sp'), "\n";
+
+$date = new \DateTimeImmutable('2023-01-25T00:00:00-00:00');
+echo $date->format('Y-m-d\TH:i:sp'), "\n";
+?>
+--EXPECT--
+2023-01-25T00:00:00Z
+2023-01-25T00:00:00Z