get_next_post/get_previous_post category exclusions still broken

[stewartjohnson]

This was broken up until version 2.1 (see the history of it at ​RonR's site).

It's still broken in WP 2.1.3. For WP 2.1.3 the code in get_next_post and get_previous_post has some harmless bugs (for example $sql_exclude_cats is declared and never used) but there's one bug preventing the fourth parameter from working correctly at all.

There’s a one line fix for WP2.1.3 to get this code to work. In both functions, this line (lines 294 and 331 in link-template.php):

$sql_cat_ids = " OR pc.category_ID = '$category'";

should be changed to

$sql_cat_ids .= " OR pc.category_ID = '$category'";

(changed = to .=)

I have tested this fix on my own installation and it works correctly.

SVN patch to fix the bug, and add some missing error checking on intval()

Your ticket was first, but it's so old that it's using the old category structure, so I'm closing as a dupe of #6551