Req #53831 [Opn->Ver]: DateInterval constructor does not handle valid ISO 8601 strings

Edit report at https://bugs.php.net/bug.php?id=53831&edit=1 ID: 53831 Updated by: googleguy@php.net Reported by: pallinger at dsd dot sztaki dot hu Summary: DateInterval constructor does not handle valid ISO 8601 strings -Status: Open +Status: Verified Type: Feature/Change Request Package: Date/time related Operating System: ubuntu linux 10.10 PHP Version: 5.3.5 -Assigned To: +Assigned To: derick Block user comment: N Private report: N New Comment: This may be considered more of a feature request than a bug, however, I'm assigning to Derrick and pinging them here. When I looked at "Appendix A. ISO 8601 Collected ABNF" of RFC3339, I only see the definition of Seconds Duration as DIGIT, not fraction: Durations: dur-second = 1*DIGIT "S" dur-minute = 1*DIGIT "M" [dur-second] dur-hour = 1*DIGIT "H" [dur-minute] dur-time = "T" (dur-hour / dur-minute / dur-second) dur-day = 1*DIGIT "D" dur-week = 1*DIGIT "W" dur-month = 1*DIGIT "M" [dur-day] dur-year = 1*DIGIT "Y" [dur-month] dur-date = (dur-day / dur-month / dur-year) [dur-time] Additionally, section 5.3 of the RFC may seem to indicate that this not required by the specification: --- 5.3. Rarely Used Options A format which includes rarely used options is likely to cause interoperability problems. This is because rarely used options are less likely to be used in alpha or beta testing, so bugs in parsing are less likely to be discovered. Rarely used options should be made mandatory or omitted for the sake of interoperability whenever possible. The format defined below includes only one rarely used option: fractions of a second. It is expected that this will be used only by applications which require strict ordering of date/time stamps or which have an unusual precision requirement. --- However, I'll leave this to Derick to decide. It does seem to be a highly sought after feature and it would make sense to add it in the interval spec. Derick, any thoughts on this? Previous Comments: ------------------------------------------------------------------------ [2019-01-10 19:15:05] mdwyer at michaelmdwyer dot com This appears to still be an issue with PHP 7.2, despite them adding a microseconds field to DateInterval. My current workaround is: $fractional = new DateInterval('PT0S'); $fractional->f = ".{$microseconds}"; $fractional->invert = $seconds < 0; return (new DateTime("@{$seconds}"))->add($fractional); ------------------------------------------------------------------------ [2017-12-05 22:46:04] sloanlance+php dot net at gmail dot com I'm surprised this bug has persisted since 2011-01-24. This seems to have been implemented incorrectly from the beginning. ISO 8601 has mentioned support for fractional parts since at least 2004. That is, it supports a decimal fraction to the smallest time value in a representation. For example, the following representations are valid ISO 8601 intervals, but will cause the DateInterval constructor to throw exceptions: P0.5Y P2.3D P1DT1.5H PT585.829S I appreciate the attempted workaround by "jdp2234 at hotmail dot com", but it appears to only support milliseconds. It doesn't seem to address fractions in other parts of interval representations. ------------------------------------------------------------------------ [2012-04-02 10:47:20] jdp2234 at hotmail dot com http://joshp.me/dateinterval-milliseconds/ Quick class to get around it, while the bug still exists... class DateIntervalFractions extends DateInterval { public $milliseconds; public function __construct($interval_spec) { $this->milliseconds = 0; $matches = array(); preg_match_all("#([0-9]*[.,]?[0-9]*) [S]#",$interval_spec,$matches); foreach ($matches[0] as $result) { $original = $result; list($seconds,$milliseconds) = explode(".",substr($result,0,-1)); $this->milliseconds = $milliseconds / pow(10,strlen($milliseconds) - 3); // Replace the milliseconds back to seconds, // and let the original constructor do the rest. $interval_spec = str_replace($original,$seconds . "S",$interval_spec); } parent::__construct($interval_spec); } } ------------------------------------------------------------------------ [2011-10-12 16:09:31] dagguh at gmail dot com http://en.wikipedia.org/wiki/Iso8601#Durations This decimal fraction may be specified with either a comma or a full stop, as in "P0,5Y" or "P0.5Y". Remember to accept both comma and a full stop. ------------------------------------------------------------------------ [2011-01-24 18:41:19] pallinger at dsd dot sztaki dot hu Description: ------------ --- From manual page: http://www.php.net/dateinterval.construct --- The documentation says that "Each duration period is represented by an integer value followed by a period designator.", however, the ISO 8601 allows non-integer values for the last number (http://en.wikipedia.org/wiki/ISO_8601#Durations). This is quite important if I want to parse XML data which contains millisecond-precision durations, as the seconds will surely not be integers. Test script: --------------- <?php var_dump(new DateInterval('PT1.1S')); ?> Expected result: ---------------- Should print out a valid DateInterval object, eg.: object(DateInterval)#1 (8) { ["y"]=> int(0) ["m"]=> int(0) ["d"]=> int(0) ["h"]=> int(0) ["i"]=> int(0) ["s"]=> float(1.1) ["invert"]=> int(0) ["days"]=> bool(false) } It could also include a millisecond/microsecond/nanosecond field to accomodate additional precision. However, if the durations that are stored are still integers, it would be difficult to handle durations like "P0.5Y". Actual result: -------------- PHP Fatal error: Uncaught exception 'Exception' with message 'DateInterval::__construct(): Unknown or bad format (PT1.1S)' in -:1 Stack trace: #0 -(1): DateInterval->__construct('PT1.1S') #1 {main} thrown in - on line 1 ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=53831&edit=1