ISO8601 lolphp

gistfile1.txt

No it's not valid ISO8601

> ISO8601 has multiple valid representations

that is true, for example


    Basic format: YYYYMMDD Example: 19850412
    Extended format: YYYY-MM-DD Example: 1985-04-12



> making PHP's DateTime::ISO8601 completely within the specification of the standard

that's not true (or at the very least it's not true in ISO8601:2004, the only revision i have access to), the first part `1970-01-01T01:00:00` is a valid extended-format, and now for adding the timezone, in **BASIC** format, this is legal (per section `4.3.2 Complete representations`):

    YYYYMMDDThhmmss±hhmm 19850412T101530+0400
    YYYYMMDDThhmmss±hh 19850412T101530+04 

- that's legal in basic format, and is ***how PHP adds the timezone***, but that's not legal in extended format, here's how to add it in extended format:

 

    Extended format: YYYY-MM-DDThh:mm:ss Example: 1985-04-12T10:15:30
    YYYY-MM-DDThh:mm:ssZ 1985-04-12T10:15:30Z
    YYYY-MM-DDThh:mm:ss±hh:mm 1985-04-12T10:15:30+04:00
    YYYY-MM-DDThh:mm:ss±hh 1985-04-12T10:15:30+04


- now what does php do? it starts out with legal extended format illegal basic format `1970-01-01T01:00:00` ... and then it ends with legal basic format illegal extended format: `+0100` - in all of ISO8601:2004 i can't find a single example where the standard is ***mixing*** extended format with basic format, and i can't find a single statement saying "you're allowed to mix basic format with extended format" either. PHP's DateTime::ISO8601 format is a *mix* of starting with legal extended format, and ending with legal basic format, that mix is not allowed per ISO8601:2004.


edit: found this, which quite clearly states that mixing extended with basic is *NOT* legal, quoting section 4.3.3 of ISO8601:2004:

    For reduced accuracy, decimal or expanded representations of date and time of day, any of the
    representations in 4.1.2 (calendar dates), 4.1.3 (ordinal dates) or 4.1.4 (week dates) followed immediately by
    the time designator [T] may be combined with any of the representations in 4.2.2.2 through 4.2.2.4 (local time),
    4.2.4 (UTC of day) or 4.2.5.2 (local time and the difference from UTC) provided that
    (...skipped stuff...)
    d) the expression shall either be completely in basic format, in which case the minimum number of
    separators necessary for the required expression is used, or completely in extended format, in which case
    additional separators shall be used in accordance with 4.1 and 4.2.