Twenty Twelve: hide category and tag output in post meta if only 1 term

[lancewillett]

Props ryanimel and iandstewart for the report and idea for fix.

First patch attached.

Patch from ryanimel

In ​21479.2.patch, I've simplified and cleaned up the function in several ways:

• I don't think it helps anything to cache the function in a transient as get_categories calls get_terms which has caching built-in
• Renamed the function to 'twentytwelve_is_categorized_site' to be a bit more descriptive about what it does
• Renamed the variable $all_the_cool_cats to $non_empty_categories to be a bit more descriptive about it is
• Simplified the if statements

Modifying ryanimel's patch to flush out the cool cats when a user delete's categories too (and props to ryanimel for catching that right away)

jkudish FTW. Much simpler.

In [21444]:

Twenty Twelve: hide category and tag output in post meta if only 1 term. Props ryanimel, jkudish and fixes #21479.

In [21449]:

Twenty Twelve: check for empty variable for simpler logic, props jkudish. See #21479.

In [21489]:

Twenty Twelve: make twentytwelve_is_categorized_site() pluggable, see #21479.

This looks like it would be running extra queries on the frontend. We should be sure they are necessary.

! empty( $categories_list ) can simply be $categories_list. Also, count() is unnecessary when empty() is already there.

Replying to nacin:

! empty( $categories_list ) can simply be $categories_list.

Agreed.

Also, count() is unnecessary when empty() is already there.

The check is supposed to return false if only 1 category exists. So, the check should be count( $non_empty_categories ) < 2 instead, right?

Simpler check and correct logic for 0 or 1 category existing

We could use wp_count_terms(), which performs a faster query (SELECT COUNT(*) instead of requesting all the category data, 0.8ms vs. 4.0ms on my install).

21479.4.patch​ also simplifies the $tag_list check.

21479.5.diff​ builds on @SergeyBiryukov's patch, further simplifying the is_categorized() check.

Replying to SergeyBiryukov:

We could use wp_count_terms(), which performs a faster query (SELECT COUNT(*) instead of requesting all the category data, 0.8ms vs. 4.0ms on my install).

Nice. :)

Ryan and Ian — can you weigh in on why you think this UX improvement is worth adding extra queries to each page load?

Discussing today in #wordpress-dev IRC Nacin is voting to remove this and "just live with Uncategorized."

If no votes for why the UX is important for the default theme to hide "Uncategorized" from display, we'll revert and punt this to a better fix on the core side, meaning only 1 category and it's named Uncategorized will be the same as having 0 categories on the front end.

Better to fix it in core for all themes than just one theme here.

Replying to lancewillett:

can you weigh in on why you think this UX improvement is worth adding extra queries to each page load?

It doesn't make sense to display only 1 category if every post is in that category. One category is no categories, imo. I think it's confusing for new users and worse, just plain ugly if that category is uncategorized -- though I'd feel the same way no matter what that one category was named. It's also annoying for users using WordPress as a small CMS for brochure sites where they may not be using any categories at all. We do it with tags, we should do it with categories.

+1 for this being in core and available for every theme -- with a new template tag. Themes need to be able to make markup for category lists conditional on there actually being categories to theme.

Better in core than a theme, absolutely. It would be nice if the theme could have it in, just for the sake of working that way sooner, but I understand not wanting to add extra queries. +1 for core too.

In [21543]:

Twenty Twelve: remove twentytwelve_is_categorized_site() in favor of a theme-agnostic future core fix for this issue, see #21479.

Also simplify the logic for checking tag and categories, props SergeyBiryukov and obenland.

See #14901 for a possibly related discussion for hiding Uncategorized in front-end display.

Closing this as the solution should not be in the theme itself.