improvements for submitting new categories via wp-admin/categories.php

[prokurator]

There are 2 things I would like to improve wile submitting new category into WP.

1. If user by accident chose category name which is already exists in the system
2. If user by accident hit submit without entering any category name (category name is empty).

In order to fix this problems 3 files need to be updated.

1. wp-admin/admin-ajax.php

add after line 132 (case 'add-cat')
following code:
##################

$cat = wp_insert_category($_POST);
if ( !$cat ) #= wp_insert_category( $_POST ) )

die('4');

$rr = $cat;
if (is_string($rr) && preg_match('/same/',$rr))

die('5');

# if ( !$cat = wp_insert_category( $_POST ) )
# die('0');
##################

2. wp-admin/admin-db.php

add in the function wp_insert_category($catarr)
after line 85
following code:
#############

$ccat = $wpdb->get_var("SELECT COUNT(*) FROM $wpdb->categories WHERE cat_name = '$cat_name'");
if ($ccat)

return 'same';

#############

3. /wp-includes/js/wp-ajax-js.php

add after line 61 (in ParseAjaxResponse)
following code or make adjustment to existing error definition:
else if ( 4 == r ) {

Element.update(this.myResponseElement,"<div class='error'><p><?php _e("Something strange happened. Category field is empty."); ?></p></div>");
return false;

} else if ( 5 == r ) {

Element.update(this.myResponseElement,"<div class='error'><p><?php _e("Something strange happened. The same category name already exists."); ?></p></div>");
return false;

}

Patch it up!

But instead of:

"Something strange happened. The same category name already exists."

Do:

"The same category name already exists."

We know what happened... no need to attribute it to mystical forces. :-)

I think this fixes #3683 too but I'm not in a position to test at the moment.

On trunk you get visual feedback if the box is empty already.

But you can add an identically named category but you don't end up with two.

Uploading a patch which stops duplicate category creation.

However the current ajax code doesn't seem to display any errors that are returned.

mdawaffe any clues?

Updated patch for trunk

It's because of a JS error in wp-ajax-response.

Attached fixes the error and tells wp-ajax-response what field to turn red on error.

(In [7336]) Don't allow duplicate category creation. Props westi and mdawaffe. fixes #3799