WP_Posts_List_Table::prepare_items()

Compatibility

Present in every tracked release (6.7.7 to 7.1.0), and compiles on PHP 7.4 through 8.6-dev.

Performance profile

How much work a call to WP_Posts_List_Table::prepare_items() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.

Cost class

Heavy

Reads stored settings via get_option(), cached per request but not free on a cold cache.

Scaling

Scales with input

The body loops, so the work grows with how much data it finds.

Instructions

54–109

Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 130.

Plugin surface

1 hook

Third-party callbacks on 'edit_posts_per_page' run inside this call, and their cost is not bounded by anything here.

Called by

0

Nothing in core calls this; the cost is only what you spend yourself.

What it touches

• hookthird-party callbacksapply_filters()called directly
• optionoption read or writeget_option()one call below WP_Posts_List_Table::prepare_items()
• cacheobject cachewp_cache_get()one call below WP_Posts_List_Table::prepare_items()

Further down the call graph this can also reach serialize, query and transient. Those are the worst case, several calls deep and usually down an error path, not what a normal call pays.

What one call costs · 12 distinct outcomes

One number would be a lie: the work depends on which branch runs. These are every distinct cost WP_Posts_List_Table::prepare_items() can have, taken from its control-flow graph on PHP 8.5.

Hooks and filters fired · 1

One hook fires while WP_Posts_List_Table::prepare_items() runs, in this order:

1. 1
   apply_filters( edit_posts_per_page )filterline 176 (+22 into the body)

   Filters the number of posts displayed per page when specifically listing "posts".

Uses · 12

• set_user_setting()Adds or updates user interface setting.
• get_user_setting()Retrieves user interface setting value based on setting name.
• wp_edit_posts_query()Runs the query to fetch the posts for listing on the edit posts page.
• is_post_type_hierarchical()Determines whether the post type is hierarchical.
• apply_filters()Calls the callback functions that have been added to a filter hook.
• wp_count_posts()Counts number of posts of a post type and if user has permissions to view.
• get_current_user_id()Gets the current user's ID.
• get_post_stati()Gets a list of post statuses.
• WP_Posts_List_Table::set_hierarchical_display()Sets whether the table layout should be hierarchical or not.
• WP_Posts_List_Table::get_items_per_page()
• WP_Posts_List_Table::get_pagenum()
• WP_Posts_List_Table::set_pagination_args()

Source code

View on Trac ↗View on GitHub ↗

154	public function prepare_items() {155		global $mode, $avail_post_stati, $wp_query, $per_page;156 157		if ( ! empty( $_REQUEST['mode'] ) ) {158			$mode = 'excerpt' === $_REQUEST['mode'] ? 'excerpt' : 'list';159			set_user_setting( 'posts_list_mode', $mode );160		} else {161			$mode = get_user_setting( 'posts_list_mode', 'list' );162		}163 164		// Is going to call wp().165		$avail_post_stati = wp_edit_posts_query();166 167		$this->set_hierarchical_display(168			is_post_type_hierarchical( $this->screen->post_type )169			&& 'menu_order title' === $wp_query->query['orderby']170		);171 172		$post_type = $this->screen->post_type;173		$per_page  = $this->get_items_per_page( 'edit_' . $post_type . '_per_page' );174 175		/** This filter is documented in wp-admin/includes/post.php */176		$per_page = apply_filters( 'edit_posts_per_page', $per_page, $post_type );177 178		if ( $this->hierarchical_display ) {179			$total_items = $wp_query->post_count;180		} elseif ( $wp_query->found_posts || $this->get_pagenum() === 1 ) {181			$total_items = $wp_query->found_posts;182		} else {183			$post_counts = (array) wp_count_posts( $post_type, 'readable' );184 185			if ( isset( $_REQUEST['post_status'] ) && in_array( $_REQUEST['post_status'], $avail_post_stati, true ) ) {186				$total_items = $post_counts[ $_REQUEST['post_status'] ];187			} elseif ( isset( $_REQUEST['show_sticky'] ) && $_REQUEST['show_sticky'] ) {188				$total_items = $this->sticky_posts_count;189			} elseif ( isset( $_GET['author'] ) && get_current_user_id() === (int) $_GET['author'] ) {190				$total_items = $this->user_posts_count;191			} else {192				$total_items = array_sum( $post_counts );193 194				// Subtract post types that are not included in the admin all list.195				foreach ( get_post_stati( array( 'show_in_admin_all_list' => false ) ) as $state ) {196					$total_items -= $post_counts[ $state ];197				}198			}199		}200 201		$this->is_trash = isset( $_REQUEST['post_status'] ) && 'trash' === $_REQUEST['post_status'];202 203		$this->set_pagination_args(204			array(205				'total_items' => $total_items,206				'per_page'    => $per_page,207			)208		);209	}

Changelog

Unchanged from 6.7.7 through 7.1.0.

1. 6.7.7
2. 6.8.8
3. 6.9.7
4. 7.0.4
5. 7.1.0

Signature, return type and hooks compared across 5 parsed releases.

About this page

Parsed data

Generated from the wordpress-develop 7.0.4 tag, from src/wp-admin/includes/class-wp-posts-list-table.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.

Corrections

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