src/Core/TypeManager.php
protected function valueToDate($format, $value)
    {
        // ISO format YYYY-MM-DD as input
        if ($value == "0000-00-00") {
            return "";
        }
        if (!$value) {
            return "";
        }
        if (strlen(trim($value)) < 1) {
            return "";
        }
        $tt = strtotime($value);
        if ($tt != - 1) {
            return strftime($format, strtotime($value));
        }
        return "";
    }
protected function valueToDate($format, $value)
    {
        // ISO format YYYY-MM-DD as input
        if ($value == "0000-00-00") {
            return "";
        }
        if (!$value) {
            return "";
        }
        if (strlen(trim($value)) < 1) {
            return "";
        }
        $tt = strtotime($value);
        if ($tt != - 1) {
            return strftime($format, strtotime($value));
        }
        return "";
    }
Format value to date

@param string $format - type format
@param string $value - value
@return string - Empty string or formatted Time/Date