get_mu_plugins(): array[]
- Since
- 3.0.0
- Source
wp-admin/includes/plugin.php:365
Description
WordPress only includes mu-plugin files in the base mu-plugins directory (wp-content/mu-plugins).
Compatibility
- WordPress
- since 3.0.0
- PHP
- 7.4–8.6-dev
- 6.7.7
- 6.8.8
- 6.9.7
- 7.0.4
- 7.1.0
Present in every tracked release (6.7.7 to 7.1.0), and compiles on PHP 7.4 through 8.6-dev.
Return value
array[]- Array of arrays of mu-plugin data, keyed by plugin file name. See get_plugin_data().
Performance profile
How much work a call to get_mu_plugins() 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
- Scaling
- Scales with input
- Instructions
- 8–46
- Plugin surface
- None
- Called by
- 2
Reads or writes the filesystem via is_dir().
The body loops, so the work grows with how much data it finds.
Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 79.
Nothing here hands control to plugin code.
2 places in core call this, so the cost is paid more often than your own code shows.
What it touches
- filesystemfilesystem access
is_dir()called directly
Further down the call graph this can also reach hook, query, option, cache, serialize 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 · 5 distinct outcomes
One number would be a lie: the work depends on which branch runs. These are every distinct cost get_mu_plugins() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
!is_dir() | 8 | is_dir() |
is_dir() | 16 | is_dir(), opendir() |
is_dir() && $file === false && empty($plugin_files) | 29 | is_dir(), opendir(), readdir(), closedir() |
is_dir() && $file === false && !empty($plugin_files) && !isset($wp_plugins) | 37–38 | is_dir(), opendir(), readdir(), closedir(), uasort() |
is_dir() && $file === false && !empty($plugin_files) && isset($wp_plugins) | 44–46 | is_dir(), opendir(), readdir(), closedir(), filesize(), uasort() |
Across PHP versions
| PHP | Compiled | Executed | Branches | Notes |
|---|---|---|---|---|
| 8.6-dev | 79 | 8–46 | 11 | |
| 8.5 | 79 | 8–46 | 11 | |
| 8.4 | 79 | 8–46 | 11 | |
| 8.3 | 79 | 8–46 | 11 | |
| 8.2 | 79 | 8–46 | 11 | 2 more instructions than PHP 8.1 |
| 8.1 | 77 | 8–51 | 11 | |
| 7.4 | 77 | 8–51 | 11 |
An instruction is not a fixed amount of time, so a matching count is not necessarily the same speed; what it rules out is a difference in the work itself.
Uses · 2
- str_ends_with()Polyfill for `str_ends_with()` function added in PHP 8.0.
- get_plugin_data()Parses the plugin contents to retrieve plugin's metadata.
Used by · 2
- WP_Debug_Data::get_wp_mu_plugins()Gets the WordPress MU plugins section of the debug data.
- WP_Plugins_List_Table::prepare_items()Prepares the list of items for displaying.
Source code
function get_mu_plugins() { $wp_plugins = array(); $plugin_files = array(); if ( ! is_dir( WPMU_PLUGIN_DIR ) ) { return $wp_plugins; } // Files in wp-content/mu-plugins directory. $plugins_dir = @opendir( WPMU_PLUGIN_DIR ); if ( $plugins_dir ) { while ( ( $file = readdir( $plugins_dir ) ) !== false ) { if ( str_ends_with( $file, '.php' ) ) { $plugin_files[] = $file; } } } else { return $wp_plugins; } closedir( $plugins_dir ); if ( empty( $plugin_files ) ) { return $wp_plugins; } foreach ( $plugin_files as $plugin_file ) { if ( ! is_readable( WPMU_PLUGIN_DIR . "/$plugin_file" ) ) { continue; } // Do not apply markup/translate as it will be cached. $plugin_data = get_plugin_data( WPMU_PLUGIN_DIR . "/$plugin_file", false, false ); if ( empty( $plugin_data['Name'] ) ) { $plugin_data['Name'] = $plugin_file; } $wp_plugins[ $plugin_file ] = $plugin_data; } if ( isset( $wp_plugins['index.php'] ) && filesize( WPMU_PLUGIN_DIR . '/index.php' ) <= 30 ) { // Silence is golden. unset( $wp_plugins['index.php'] ); } uasort( $wp_plugins, '_sort_uname_callback' ); return $wp_plugins;}Changelog
Introduced in 3.0.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
About this page
- Parsed data
- Generated from the wordpress-develop 7.1.0 tag, from
src/wp-admin/includes/plugin.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it. - Corrections
- Something wrong on this page? Report it and it gets fixed in the next regeneration.