XML-RPC returns invalid dates if the date is zero

[koke]

When a post has a 'pending' status, post_date_gmt is set to 0000-00-00 00:00:00 as a marker to update post_date when it's saved (see #5698).

mysql2date then proceeds to turn that date into a negative one, and IXR_Date destroys the thing a bit more, so 0000-00-00 00:00:00 turns into -0001113TT0::0::00, which is an invalid ISO8601 date

Added a patch which sets the post_date_gmt value to the converted post_date for pending and auto-draft posts.

Related #16985 #18998

Looks good to me.

Also, IXR_Date doesn't like "weird" dates.

• mysql2date returns -00011130T00:00:00. It looks weird but it makes sense: 0000-00-00 -> -1-12-00 -> -1-11-30
• IXR_Date works by taking substrings, and the leading '-' is what breaks everything.

Using a NULL for a 'zero' date might make sense, but I wonder how many things would break, probably including XML-RPC :(

Added a new patch at #18429 that also fixes this issue. Do need to test it tomorrow if it works as it should.

In [20153]:

XMLRPC: Intoduce a date generation helper method to improve the dates returned over XMLRPC when we have a 0 date stored for drafts.

This improves the ability of clients to work with the new wp Post APIs. See #18429 and #19733 props maxcutler.

Added a patch that applies the patch of maxcutler to all the methods. I didn't applied the code of the first patch of this ticket. Is that still needed?

I would really like to have the last patch in 3.4 but I also really don't want to commit it without us adding test cases because I just found a bunch of bugs in the featured image stuff we applied everywhere by writing the basic test cases for mw_(new|edit)_Post.

If someone wants to write up some tests to cover the date stuff that would be really helpful.

I applied the patch of koke in a way that it only applies for incorrect dates. No matter what the post status is.
I also applied it to all the new XML-RPC methods so everything has the same date handling.

A benefit for this patch is that _convert_date and _convert_date_gmt only return an IXR_Date.

I took a look at the last patch and all looks good apart from:

• _convert_mysql2date is a level of abstraction too far - lets just call mysql2date directly.
• $this-> _convert_date( $date_gmt ); - space in this.

@markoheijnen could you give the patch a refresh to address these?

Fixed that in patch-core-19733-5.diff

In [20353]:

XMLRPC: Make sure that we always return valid dates when no date is currently set - for example if the post is pending. Fixes #19733 props markoheijnen and koke.