Format constraint and date-time with fractions

[jenschude]

The date-time is not handling the fraction part of a datetime string correctly

To the FormatTest::getValidFormats should be added following cases:

        array('2000-05-01T12:12:12.123Z', 'date-time'),
        array('2000-05-01T12:12:12.123+01:00', 'date-time'),
        array('2000-05-01T12:12:12.123+0100', 'date-time'),
        array('2000-05-01T12:12:12.123456+01:00', 'date-time'),
        array('2000-05-01T12:12:12.123456+0100', 'date-time'),

And in the function FormatConstraint::check the case 'date-time' should be changed to:

        case 'date-time':
            if (!$this->validateDateTime($element, 'Y-m-d\TH:i:sT') &&
                !$this->validateDateTime($element, 'Y-m-d\TH:i:s.uT') &&
                !$this->validateDateTime($element, 'Y-m-d\TH:i:sP') &&
                !$this->validateDateTime($element, 'Y-m-d\TH:i:s.uP') &&
                !$this->validateDateTime($element, 'Y-m-d\TH:i:sO') &&
                !$this->validateDateTime($element, 'Y-m-d\TH:i:s.uO')
            ) {
                $this->addError($path, sprintf('Invalid date-time %s, expected format YYYY-MM-DDThh:mm:ssZ or YYYY-MM-DDThh:mm:ss+hh:mm', json_encode($element)));
            }
            break;

The T is better than \Z because this way the timezone part from the string will be correctly read. Important if the script is not running with UTC timezone. And the FormatConstraint::validateDateTime can now be changed to this, so that the tests will work:

protected function validateDateTime($datetime, $format)
{
    $dt = \DateTime::createFromFormat($format, $datetime);

    if (!$dt) {
        return false;
    }
    if (strpos($format, '.u') > 0 ) {
        $dtTest = new \DateTime($datetime);
        return $dt == $dtTest;
    }
    return $datetime === $dt->format($format);
}

So that when a fraction is included in the datetime string, it will be checked if reading from format and just a plain DateTime instance will have the same value.

[bighappyface]

Closed with #238

Please re-open if necessary.