Changeset 23618

Timestamp:

03/05/2013 04:14:14 PM (9 years ago)

Author:

nacin

Message:

Properly handle timezones in get_date_from_gmt() rather than relying on the implicit gmt_offset. This offset is only good for the current time, rather than the passed time, which causes problems when converting a DST date when DST is not in effect, or vice versa.

Update get_gmt_from_date() to make these functions match in formatting, as they are complementary and just reverse a few operations.

props scholesmafia
Tests: [1233/tests]

fixes #20328.

File:

• trunk/wp-includes/formatting.php (modified) (2 diffs)

trunk/wp-includes/formatting.php

@@ -1907 +1907 @@
  * Returns a date in the GMT equivalent.
  *
- * Requires and returns a date in the Y-m-d H:i:s format. Simply subtracts the
- * value of the 'gmt_offset' option. Return format can be overridden using the
- * $format parameter. The DateTime and DateTimeZone classes are used to respect
- * time zone differences in DST.
+ * Requires and returns a date in the Y-m-d H:i:s format. If there is a
+ * timezone_string available, the date is assumed to be in that timezone,
+ * otherwise it simply subtracts the value of the 'gmt_offset' option. Return
+ * format can be overridden using the $format parameter.
  *
  * @since 1.2.0
@@ -1919 +1919 @@
  * @return string GMT version of the date provided.
  */
-function get_gmt_from_date($string, $format = 'Y-m-d H:i:s') {
-    preg_match('#([0-9]{1,4})-([0-9]{1,2})-([0-9]{1,2}) ([0-9]{1,2}):([0-9]{1,2}):([0-9]{1,2})#', $string, $matches);
-    if ( ! $matches )
-        return date( $format, 0 );
-
-    $tz = get_option('timezone_string');
+function get_gmt_from_date( $string, $format = 'Y-m-d H:i:s' ) {
+    $tz = get_option( 'timezone_string' );
     if ( $tz ) {
-        date_default_timezone_set( $tz );
-        $datetime = date_create( $string );
+        $datetime = date_create( $string, new DateTimeZone( $tz ) );
+        if ( ! $datetime )
+            return gmdate( $format, 0 );
+        $datetime->setTimezone( new DateTimeZone( 'UTC' ) );
+        $string_gmt = $datetime->format( $format );
+    } else {
+        if ( ! preg_match( '#([0-9]{1,4})-([0-9]{1,2})-([0-9]{1,2}) ([0-9]{1,2}):([0-9]{1,2}):([0-9]{1,2})#', $string, $matches ) )
+            return gmdate( $format, 0 );
+        $string_time = gmmktime( $matches[4], $matches[5], $matches[6], $matches[2], $matches[3], $matches[1] );
+        $string_gmt = gmdate( $format, $string_time - get_option( 'gmt_offset' ) * HOUR_IN_SECONDS );
+    }
+    return $string_gmt;
+}
+
+/**
+ * Converts a GMT date into the correct format for the blog.
+ *
+ * Requires and returns a date in the Y-m-d H:i:s format. If there is a
+ * timezone_string available, the returned date is in that timezone, otherwise
+ * it simply adds the value of gmt_offset. Return format can be overridden
+ * using the $format parameter
+ *
+ * @since 1.2.0
+ *
+ * @param string $string The date to be converted.
+ * @param string $format The format string for the returned date (default is Y-m-d H:i:s)
+ * @return string Formatted date relative to the timezone / GMT offset.
+ */
+function get_date_from_gmt( $string, $format = 'Y-m-d H:i:s' ) {
+    $tz = get_option( 'timezone_string' );
+    if ( $tz ) {
+        $datetime = date_create( $string, new DateTimeZone( 'UTC' ) );
         if ( ! $datetime )
             return date( $format, 0 );
-
-        $datetime->setTimezone( new DateTimeZone('UTC') );
-        $offset = $datetime->getOffset();
-        $datetime->modify( '+' . $offset / HOUR_IN_SECONDS . ' hours');
-        $string_gmt = gmdate($format, $datetime->format('U'));
-
-        date_default_timezone_set('UTC');
+        $datetime->setTimezone( new DateTimeZone( $tz ) );
+        $string_localtime = $datetime->format( $format );
     } else {
-        $string_time = gmmktime($matches[4], $matches[5], $matches[6], $matches[2], $matches[3], $matches[1]);
-        $string_gmt = gmdate($format, $string_time - get_option('gmt_offset') * HOUR_IN_SECONDS);
-    }
-    return $string_gmt;
-}
-
-/**
- * Converts a GMT date into the correct format for the blog.
- *
- * Requires and returns in the Y-m-d H:i:s format. Simply adds the value of
- * gmt_offset.Return format can be overridden using the $format parameter
- *
- * @since 1.2.0
- *
- * @param string $string The date to be converted.
- * @param string $format The format string for the returned date (default is Y-m-d H:i:s)
- * @return string Formatted date relative to the GMT offset.
- */
-function get_date_from_gmt($string, $format = 'Y-m-d H:i:s') {
-    preg_match('#([0-9]{1,4})-([0-9]{1,2})-([0-9]{1,2}) ([0-9]{1,2}):([0-9]{1,2}):([0-9]{1,2})#', $string, $matches);
-    $string_time = gmmktime($matches[4], $matches[5], $matches[6], $matches[2], $matches[3], $matches[1]);
-    $string_localtime = gmdate($format, $string_time + get_option('gmt_offset') * HOUR_IN_SECONDS);
+        if ( ! preg_match('#([0-9]{1,4})-([0-9]{1,2})-([0-9]{1,2}) ([0-9]{1,2}):([0-9]{1,2}):([0-9]{1,2})#', $string, $matches) )
+            return date( $format, 0 );
+        $string_time = gmmktime( $matches[4], $matches[5], $matches[6], $matches[2], $matches[3], $matches[1] );
+        $string_localtime = gmdate( $format, $string_time + get_option( 'gmt_offset' ) * HOUR_IN_SECONDS );
+    }
     return $string_localtime;
 }