WP_REST_Request->get_params strips numeric keys

[sswells]

Right now, a numeric key is getting stripped.

Request Body = {"41150":"API value"}

$request->get_params = [1] => API value

So line 453 in class-wp-rest-request.php:
$params = array_merge( $params, (array) $this->params[ $type ] );

should be:
$params = $params + (array) $this->params[ $type ];

Any chance of getting this into 4.7?

[rachelbaker]

@sswells We cannot use the combine operator for the associative arrays because it does not merge arrays recursively. See ​https://3v4l.org/ultWd

It looks like the only way to patch this correctly needs to allow numeric array keys to be retained without being re-indexed, while still merging recursive data as well.

[sswells]

Thanks. I didn't think about that since my test data was flat. Looks like my fix won't cover it then.

[rachelbaker]

@joehoyle Saw you milestoned this as 4.7. Are you going to shepherd this ticket before beta?

[joehoyle]

@rachelbaker yes! Set myself as owner.

[rachelbaker]

While discussing this ticket with @joehoyle he pointed out that @sswells was using a numeric string in her array key, and that would result in the + operator recursively combining the arrays: ​https://3v4l.org/qdhJC

[joehoyle]

array_merge and the + operator are both issues, as even the + will make numeric keys integers after it's done. It seems the easiest and best way is to manually implement a foreach. Added unit test also.

[rmccue]

In 39087:

REST API: Change method of merging parameters.

array_merge() incorrectly reindexes numeric parameters, causing things like {"123": true} to be "dropped".

Props sswells, joehoyle.
Fixes #38306.