A proof-of-concept WordPress plugin for ensuring URLs are unique, avoiding collisions.

This plugin is intended for WordPress core contributors to consider ways we can improve wp_unique_post_slug() internally. It is not intended for production use.

WordPress' algorithm for ensuring slug uniqueness could use some help.

• If posts and pages share the same permalink structure (e.g. example.com/%postname%/), a post and a page can have colliding slugs (see #13459).
• If there's a static blog prefix (e.g. example.com/blog/%postname%/), a page's slug can collide with a blog post.

The plugin uses WordPress' internal rewriting API to check if a desired URL is occupied.

This would fix the previously mentioned issues as well as these other cases

• A page with the desired slug /category/uncategorized/ would collide with the Uncategorized category term archive, and assume the slug /category/uncategorized-2/.
• A page with the desired slug book would collide with a custom post type archive for "book," and assume the slug /book-2/.
• Any other conflict with an existing rewrite rule.