Import nav_menu_item fails on PHP 7

[RavanH]

When I do a WordPress Export and then an Import it on another WordPress install, all menus are imported as expected but they are empty. It appears menu items are skipped for some reason.

Looking through the export xml file, I find all items of post-type nav_menu_item are there, so the problem must lie with the import.

[RavanH]

WP_DEBUG log shows these notices

[28-Apr-2017 14:45:56 UTC] PHP Notice:  Undefined variable: _menu_item_type in /home/grainsdihq/www/wp-content/plugins/wordpress-importer/wordpress-importer.php on line 886
[28-Apr-2017 14:45:56 UTC] PHP Notice:  Undefined variable: _menu_item_type in /home/grainsdihq/www/wp-content/plugins/wordpress-importer/wordpress-importer.php on line 888
[28-Apr-2017 14:45:56 UTC] PHP Notice:  Undefined variable: _menu_item_type in /home/grainsdihq/www/wp-content/plugins/wordpress-importer/wordpress-importer.php on line 890

but no errors are reported. This is on PHP7, will test on PHP5.6 now...

[RavanH]

On PHP 5.6 it turns out there is no problem with importing menu items. Issue seems PHP 7 (7.0 and 7.1) related only.

[mixoet]

Meta variables are undefined, because syntax of variable variables changed in PHP7. So if you change line 884 in wordpress-importer.php

<?php
$$meta['key'] = $meta['value'];

to

<?php
${$meta['key']} = $meta['value'];

should do the trick. Unable to test it myself.

[RavanH]

Tested and confirmed. Thanks @mixoet :)

[netweb]

For has-patch we need a patch uploaded to this ticket :)

Details on creating and uploading patches can be found in our handbook ​here.

[dd32]

Duplicate of #36281.