Fixed php#7752, php#8101, #81660: DateTimeZone::getTransitions() returns insufficient data

Author: derickr

NEWS

@@ -2,6 +2,12 @@ PHP                                                                        NEWS
 |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
 ?? ??? ????, PHP 8.1.6
 
+- Date:
+  . Fixed bug GH-7752 (DateTimeZone::getTransitions() returns insufficient
+    data). (Derick)
+  . Fixed bug GH-8108 (Timezone doesn't work as intended). (Derick)
+  . Fixed bug #81660 (DateTimeZone::getTransitions() returns invalid data).
+    (Derick)
 
 31 Mar 2022, PHP 8.1.5
 

ext/date/php_date.c

@@ -3629,6 +3629,15 @@ PHP_FUNCTION(timezone_transitions_get)
 		add_assoc_string(&element, "abbr", &tzobj->tzi.tz->timezone_abbr[tzobj->tzi.tz->type[i].abbr_idx]); \
 		add_next_index_zval(return_value, &element);
 
+#define add_from_tto(to,ts) \
+		array_init(&element); \
+		add_assoc_long(&element, "ts",     ts); \
+		add_assoc_str(&element, "time", php_format_date(DATE_FORMAT_ISO8601, 13, ts, 0)); \
+		add_assoc_long(&element, "offset", (to)->offset); \
+		add_assoc_bool(&element, "isdst",  (to)->is_dst); \
+		add_assoc_string(&element, "abbr", (to)->abbr); \
+		add_next_index_zval(return_value, &element);
+
 #define add_last() add(tzobj->tzi.tz->bit64.timecnt - 1, timestamp_begin)
 
 	array_init(return_value);
@@ -3658,7 +3667,13 @@ PHP_FUNCTION(timezone_transitions_get)
 
 	if (!found) {
 		if (tzobj->tzi.tz->bit64.timecnt > 0) {
-			add_last();
+			if (tzobj->tzi.tz->posix_info && tzobj->tzi.tz->posix_info->dst_end) {
+				timelib_time_offset *tto = timelib_get_time_zone_info(timestamp_begin, tzobj->tzi.tz);
+				add_from_tto(tto, timestamp_begin);
+				timelib_time_offset_dtor(tto);
+			} else {
+				add_last();
+			}
 		} else {
 			add_nominal();
 		}
@@ -3671,31 +3686,34 @@ PHP_FUNCTION(timezone_transitions_get)
 				return;
 			}
 		}
-		if (tzobj->tzi.tz->posix_info && tzobj->tzi.tz->posix_info->dst_end) {
-			int i, j;
-			timelib_sll start_y, end_y, dummy_m, dummy_d;
-			timelib_sll last_transition_ts = tzobj->tzi.tz->trans[tzobj->tzi.tz->bit64.timecnt - 1];
+	}
+	if (tzobj->tzi.tz->posix_info && tzobj->tzi.tz->posix_info->dst_end) {
+		int i, j;
+		timelib_sll start_y, end_y, dummy_m, dummy_d;
+		timelib_sll last_transition_ts = tzobj->tzi.tz->trans[tzobj->tzi.tz->bit64.timecnt - 1];
 
-			/* Find out year for last transition */
-			timelib_unixtime2date(last_transition_ts, &start_y, &dummy_m, &dummy_d);
+		/* Find out year for last transition */
+		timelib_unixtime2date(last_transition_ts, &start_y, &dummy_m, &dummy_d);
 
-			/* Find out year for final boundary timestamp */
-			timelib_unixtime2date(timestamp_end, &end_y, &dummy_m, &dummy_d);
+		/* Find out year for final boundary timestamp */
+		timelib_unixtime2date(timestamp_end, &end_y, &dummy_m, &dummy_d);
 
-			for (i = start_y; i <= end_y; i++) {
-				timelib_posix_transitions transitions = { 0 };
+		for (i = start_y; i <= end_y; i++) {
+			timelib_posix_transitions transitions = { 0 };
 
-				timelib_get_transitions_for_year(tzobj->tzi.tz, i, &transitions);
+			timelib_get_transitions_for_year(tzobj->tzi.tz, i, &transitions);
 
-				for (j = 0; j < transitions.count; j++) {
-					if (transitions.times[j] <= last_transition_ts) {
-						continue;
-					}
-					if (transitions.times[j] > timestamp_end) {
-						return;
-					}
-					add_by_index(transitions.types[j], transitions.times[j]);
+			for (j = 0; j < transitions.count; j++) {
+				if (transitions.times[j] <= last_transition_ts) {
+					continue;
+				}
+				if (transitions.times[j] < timestamp_begin) {
+					continue;
+				}
+				if (transitions.times[j] > timestamp_end) {
+					return;
 				}
+				add_by_index(transitions.types[j], transitions.times[j]);
 			}
 		}
 	}

ext/date/tests/DateTimeZone_getTransitions_bug1.phpt

@@ -0,0 +1,58 @@
+--TEST--
+GH-7752: DateTimeZone::getTransitions() does not return enough information
+--FILE--
+<?php
+function showTransitions(string $tzid, int $from)
+{
+	$to = $from + ((2.5 * 366) * 24 * 60 * 60);
+
+	echo "{$tzid} from @{$from}-@{$to}:\n\n";
+
+	$tz = new DateTimeZone($tzid);
+	foreach ($tz->getTransitions($from, $to) as $t) {
+		printf("%12d %s %6d %s %s\n", $t['ts'], $t['time'], $t['offset'], $t['isdst'] ? "DST" : " x ", $t['abbr']);
+	}
+	echo "\n";
+}
+
+
+showTransitions('Europe/London', 1648342200);
+showTransitions('America/Los_Angeles', 1648557596); // GH Issue 7752
+showTransitions('America/Chicago', 1293861600);     // PHP Bug 81660
+showTransitions('Europe/Paris', 1645095600);        // GH Issue 8108
+?>
+--EXPECT--
+Europe/London from @1648342200-@1727398200:
+
+  1648342200 2022-03-27T00:50:00+0000      0  x  GMT
+  1648342800 2022-03-27T01:00:00+0000   3600 DST BST
+  1667091600 2022-10-30T01:00:00+0000      0  x  GMT
+  1679792400 2023-03-26T01:00:00+0000   3600 DST BST
+  1698541200 2023-10-29T01:00:00+0000      0  x  GMT
+  1711846800 2024-03-31T01:00:00+0000   3600 DST BST
+
+America/Los_Angeles from @1648557596-@1727613596:
+
+  1648557596 2022-03-29T12:39:56+0000 -25200 DST PDT
+  1667725200 2022-11-06T09:00:00+0000 -28800  x  PST
+  1678615200 2023-03-12T10:00:00+0000 -25200 DST PDT
+  1699174800 2023-11-05T09:00:00+0000 -28800  x  PST
+  1710064800 2024-03-10T10:00:00+0000 -25200 DST PDT
+
+America/Chicago from @1293861600-@1372917600:
+
+  1293861600 2011-01-01T06:00:00+0000 -21600  x  CST
+  1300003200 2011-03-13T08:00:00+0000 -18000 DST CDT
+  1320562800 2011-11-06T07:00:00+0000 -21600  x  CST
+  1331452800 2012-03-11T08:00:00+0000 -18000 DST CDT
+  1352012400 2012-11-04T07:00:00+0000 -21600  x  CST
+  1362902400 2013-03-10T08:00:00+0000 -18000 DST CDT
+
+Europe/Paris from @1645095600-@1724151600:
+
+  1645095600 2022-02-17T11:00:00+0000   3600  x  CET
+  1648342800 2022-03-27T01:00:00+0000   7200 DST CEST
+  1667091600 2022-10-30T01:00:00+0000   3600  x  CET
+  1679792400 2023-03-26T01:00:00+0000   7200 DST CEST
+  1698541200 2023-10-29T01:00:00+0000   3600  x  CET
+  1711846800 2024-03-31T01:00:00+0000   7200 DST CEST