Title: Plugin_Upgrader
Published: April 25, 2014
Last modified: February 24, 2026
---
# class Plugin_Upgrader {}
## In this article
* [Description](https://developer.wordpress.org/reference/classes/plugin_upgrader/?output_format=md#description)
- [See also](https://developer.wordpress.org/reference/classes/plugin_upgrader/?output_format=md#see-also)
* [Methods](https://developer.wordpress.org/reference/classes/plugin_upgrader/?output_format=md#methods)
* [Source](https://developer.wordpress.org/reference/classes/plugin_upgrader/?output_format=md#source)
* [Related](https://developer.wordpress.org/reference/classes/plugin_upgrader/?output_format=md#related)
* [Changelog](https://developer.wordpress.org/reference/classes/plugin_upgrader/?output_format=md#changelog)
[ Back to top](https://developer.wordpress.org/reference/classes/plugin_upgrader/?output_format=md#wp--skip-link--target)
Core class used for upgrading/installing plugins.
## [Description](https://developer.wordpress.org/reference/classes/plugin_upgrader/?output_format=md#description)
It is designed to upgrade/install plugins from a local zip, remote zip URL, or uploaded
zip file.
### [See also](https://developer.wordpress.org/reference/classes/plugin_upgrader/?output_format=md#see-also)
* [WP_Upgrader](https://developer.wordpress.org/reference/classes/wp_upgrader/)
## [Methods](https://developer.wordpress.org/reference/classes/plugin_upgrader/?output_format=md#methods)
| Name | Description |
| [Plugin_Upgrader::active_after](https://developer.wordpress.org/reference/classes/plugin_upgrader/active_after/) | Turns off maintenance mode after upgrading an active plugin. |
| [Plugin_Upgrader::active_before](https://developer.wordpress.org/reference/classes/plugin_upgrader/active_before/) | Turns on maintenance mode before attempting to background update an active plugin. |
| [Plugin_Upgrader::bulk_upgrade](https://developer.wordpress.org/reference/classes/plugin_upgrader/bulk_upgrade/) | Upgrades several plugins at once. |
| [Plugin_Upgrader::check_package](https://developer.wordpress.org/reference/classes/plugin_upgrader/check_package/) | Checks that the source package contains a valid plugin. |
| [Plugin_Upgrader::deactivate_plugin_before_upgrade](https://developer.wordpress.org/reference/classes/plugin_upgrader/deactivate_plugin_before_upgrade/) | Deactivates a plugin before it is upgraded. |
| [Plugin_Upgrader::delete_old_plugin](https://developer.wordpress.org/reference/classes/plugin_upgrader/delete_old_plugin/) | Deletes the old plugin during an upgrade. |
| [Plugin_Upgrader::install](https://developer.wordpress.org/reference/classes/plugin_upgrader/install/) | Install a plugin package. |
| [Plugin_Upgrader::install_strings](https://developer.wordpress.org/reference/classes/plugin_upgrader/install_strings/) | Initializes the installation strings. |
| [Plugin_Upgrader::plugin_info](https://developer.wordpress.org/reference/classes/plugin_upgrader/plugin_info/) | Retrieves the path to the file that contains the plugin info. |
| [Plugin_Upgrader::upgrade](https://developer.wordpress.org/reference/classes/plugin_upgrader/upgrade/) | Upgrades a plugin. |
| [Plugin_Upgrader::upgrade_strings](https://developer.wordpress.org/reference/classes/plugin_upgrader/upgrade_strings/) | Initializes the upgrade strings. |
## [Source](https://developer.wordpress.org/reference/classes/plugin_upgrader/?output_format=md#source)
```php
class Plugin_Upgrader extends WP_Upgrader {
/**
* Plugin upgrade result.
*
* @since 2.8.0
* @var array|WP_Error $result
*
* @see WP_Upgrader::$result
*/
public $result;
/**
* Whether a bulk upgrade/installation is being performed.
*
* @since 2.9.0
* @var bool $bulk
*/
public $bulk = false;
/**
* New plugin info.
*
* @since 5.5.0
* @var array $new_plugin_data
*
* @see check_package()
*/
public $new_plugin_data = array();
/**
* Initializes the upgrade strings.
*
* @since 2.8.0
*/
public function upgrade_strings() {
$this->strings['up_to_date'] = __( 'The plugin is at the latest version.' );
$this->strings['no_package'] = __( 'Update package not available.' );
/* translators: %s: Package URL. */
$this->strings['downloading_package'] = sprintf( __( 'Downloading update from %s…' ), '%s' );
$this->strings['unpack_package'] = __( 'Unpacking the update…' );
$this->strings['remove_old'] = __( 'Removing the old version of the plugin…' );
$this->strings['remove_old_failed'] = __( 'Could not remove the old plugin.' );
$this->strings['process_failed'] = __( 'Plugin update failed.' );
$this->strings['process_success'] = __( 'Plugin updated successfully.' );
$this->strings['process_bulk_success'] = __( 'Plugins updated successfully.' );
}
/**
* Initializes the installation strings.
*
* @since 2.8.0
*/
public function install_strings() {
$this->strings['no_package'] = __( 'Installation package not available.' );
/* translators: %s: Package URL. */
$this->strings['downloading_package'] = sprintf( __( 'Downloading installation package from %s…' ), '%s' );
$this->strings['unpack_package'] = __( 'Unpacking the package…' );
$this->strings['installing_package'] = __( 'Installing the plugin…' );
$this->strings['remove_old'] = __( 'Removing the current plugin…' );
$this->strings['remove_old_failed'] = __( 'Could not remove the current plugin.' );
$this->strings['no_files'] = __( 'The plugin contains no files.' );
$this->strings['process_failed'] = __( 'Plugin installation failed.' );
$this->strings['process_success'] = __( 'Plugin installed successfully.' );
/* translators: 1: Plugin name, 2: Plugin version. */
$this->strings['process_success_specific'] = __( 'Successfully installed the plugin %1$s %2$s.' );
if ( ! empty( $this->skin->overwrite ) ) {
if ( 'update-plugin' === $this->skin->overwrite ) {
$this->strings['installing_package'] = __( 'Updating the plugin…' );
$this->strings['process_failed'] = __( 'Plugin update failed.' );
$this->strings['process_success'] = __( 'Plugin updated successfully.' );
}
if ( 'downgrade-plugin' === $this->skin->overwrite ) {
$this->strings['installing_package'] = __( 'Downgrading the plugin…' );
$this->strings['process_failed'] = __( 'Plugin downgrade failed.' );
$this->strings['process_success'] = __( 'Plugin downgraded successfully.' );
}
}
}
/**
* Install a plugin package.
*
* @since 2.8.0
* @since 3.7.0 The `$args` parameter was added, making clearing the plugin update cache optional.
*
* @param string $package The full local path or URI of the package.
* @param array $args {
* Optional. Other arguments for installing a plugin package. Default empty array.
*
* @type bool $clear_update_cache Whether to clear the plugin updates cache if successful.
* Default true.
* }
* @return bool|WP_Error True if the installation was successful, false or a WP_Error otherwise.
*/
public function install( $package, $args = array() ) {
$defaults = array(
'clear_update_cache' => true,
'overwrite_package' => false, // Do not overwrite files.
);
$parsed_args = wp_parse_args( $args, $defaults );
$this->init();
$this->install_strings();
add_filter( 'upgrader_source_selection', array( $this, 'check_package' ) );
if ( $parsed_args['clear_update_cache'] ) {
// Clear cache so wp_update_plugins() knows about the new plugin.
add_action( 'upgrader_process_complete', 'wp_clean_plugins_cache', 9, 0 );
}
$this->run(
array(
'package' => $package,
'destination' => WP_PLUGIN_DIR,
'clear_destination' => $parsed_args['overwrite_package'],
'clear_working' => true,
'hook_extra' => array(
'type' => 'plugin',
'action' => 'install',
),
)
);
remove_action( 'upgrader_process_complete', 'wp_clean_plugins_cache', 9 );
remove_filter( 'upgrader_source_selection', array( $this, 'check_package' ) );
if ( ! $this->result || is_wp_error( $this->result ) ) {
return $this->result;
}
// Force refresh of plugin update information.
wp_clean_plugins_cache( $parsed_args['clear_update_cache'] );
if ( $parsed_args['overwrite_package'] ) {
/**
* Fires when the upgrader has successfully overwritten a currently installed
* plugin or theme with an uploaded zip package.
*
* @since 5.5.0
*
* @param string $package The package file.
* @param array $data The new plugin or theme data.
* @param string $package_type The package type ('plugin' or 'theme').
*/
do_action( 'upgrader_overwrote_package', $package, $this->new_plugin_data, 'plugin' );
}
return true;
}
/**
* Upgrades a plugin.
*
* @since 2.8.0
* @since 3.7.0 The `$args` parameter was added, making clearing the plugin update cache optional.
*
* @param string $plugin Path to the plugin file relative to the plugins directory.
* @param array $args {
* Optional. Other arguments for upgrading a plugin package. Default empty array.
*
* @type bool $clear_update_cache Whether to clear the plugin updates cache if successful.
* Default true.
* }
* @return bool|WP_Error True if the upgrade was successful, false or a WP_Error object otherwise.
*/
public function upgrade( $plugin, $args = array() ) {
$defaults = array(
'clear_update_cache' => true,
);
$parsed_args = wp_parse_args( $args, $defaults );
$this->init();
$this->upgrade_strings();
$current = get_site_transient( 'update_plugins' );
if ( ! isset( $current->response[ $plugin ] ) ) {
$this->skin->before();
$this->skin->set_result( false );
$this->skin->error( 'up_to_date' );
$this->skin->after();
return false;
}
// Get the URL to the zip file.
$upgrade_data = $current->response[ $plugin ];
add_filter( 'upgrader_pre_install', array( $this, 'deactivate_plugin_before_upgrade' ), 10, 2 );
add_filter( 'upgrader_pre_install', array( $this, 'active_before' ), 10, 2 );
add_filter( 'upgrader_clear_destination', array( $this, 'delete_old_plugin' ), 10, 4 );
add_filter( 'upgrader_post_install', array( $this, 'active_after' ), 10, 2 );
/*
* There's a Trac ticket to move up the directory for zips which are made a bit differently, useful for non-.org plugins.
* 'source_selection' => array( $this, 'source_selection' ),
*/
if ( $parsed_args['clear_update_cache'] ) {
// Clear cache so wp_update_plugins() knows about the new plugin.
add_action( 'upgrader_process_complete', 'wp_clean_plugins_cache', 9, 0 );
}
$this->run(
array(
'package' => $upgrade_data->package,
'destination' => WP_PLUGIN_DIR,
'clear_destination' => true,
'clear_working' => true,
'hook_extra' => array(
'plugin' => $plugin,
'type' => 'plugin',
'action' => 'update',
'temp_backup' => array(
'slug' => dirname( $plugin ),
'src' => WP_PLUGIN_DIR,
'dir' => 'plugins',
),
),
)
);
// Cleanup our hooks, in case something else does an upgrade on this connection.
remove_action( 'upgrader_process_complete', 'wp_clean_plugins_cache', 9 );
remove_filter( 'upgrader_pre_install', array( $this, 'deactivate_plugin_before_upgrade' ) );
remove_filter( 'upgrader_pre_install', array( $this, 'active_before' ) );
remove_filter( 'upgrader_clear_destination', array( $this, 'delete_old_plugin' ) );
remove_filter( 'upgrader_post_install', array( $this, 'active_after' ) );
if ( ! $this->result || is_wp_error( $this->result ) ) {
return $this->result;
}
// Force refresh of plugin update information.
wp_clean_plugins_cache( $parsed_args['clear_update_cache'] );
/*
* Ensure any future auto-update failures trigger a failure email by removing
* the last failure notification from the list when plugins update successfully.
*/
$past_failure_emails = get_option( 'auto_plugin_theme_update_emails', array() );
if ( isset( $past_failure_emails[ $plugin ] ) ) {
unset( $past_failure_emails[ $plugin ] );
update_option( 'auto_plugin_theme_update_emails', $past_failure_emails );
}
return true;
}
/**
* Upgrades several plugins at once.
*
* @since 2.8.0
* @since 3.7.0 The `$args` parameter was added, making clearing the plugin update cache optional.
*
* @param string[] $plugins Array of paths to plugin files relative to the plugins directory.
* @param array $args {
* Optional. Other arguments for upgrading several plugins at once.
*
* @type bool $clear_update_cache Whether to clear the plugin updates cache if successful. Default true.
* }
* @return array|false An array of results indexed by plugin file, or false if unable to connect to the filesystem.
*/
public function bulk_upgrade( $plugins, $args = array() ) {
$wp_version = wp_get_wp_version();
$defaults = array(
'clear_update_cache' => true,
);
$parsed_args = wp_parse_args( $args, $defaults );
$this->init();
$this->bulk = true;
$this->upgrade_strings();
$current = get_site_transient( 'update_plugins' );
add_filter( 'upgrader_clear_destination', array( $this, 'delete_old_plugin' ), 10, 4 );
$this->skin->header();
// Connect to the filesystem first.
$connected = $this->fs_connect( array( WP_CONTENT_DIR, WP_PLUGIN_DIR ) );
if ( ! $connected ) {
$this->skin->footer();
return false;
}
$this->skin->bulk_header();
/*
* Only start maintenance mode if:
* - running Multisite and there are one or more plugins specified, OR
* - a plugin with an update available is currently active.
* @todo For multisite, maintenance mode should only kick in for individual sites if at all possible.
*/
$maintenance = ( is_multisite() && ! empty( $plugins ) );
foreach ( $plugins as $plugin ) {
$maintenance = $maintenance || ( is_plugin_active( $plugin ) && isset( $current->response[ $plugin ] ) );
}
if ( $maintenance ) {
$this->maintenance_mode( true );
}
$results = array();
$this->update_count = count( $plugins );
$this->update_current = 0;
foreach ( $plugins as $plugin ) {
++$this->update_current;
$this->skin->plugin_info = get_plugin_data( WP_PLUGIN_DIR . '/' . $plugin, false, true );
if ( ! isset( $current->response[ $plugin ] ) ) {
$this->skin->set_result( 'up_to_date' );
$this->skin->before();
$this->skin->feedback( 'up_to_date' );
$this->skin->after();
$results[ $plugin ] = true;
continue;
}
// Get the URL to the zip file.
$upgrade_data = $current->response[ $plugin ];
$this->skin->plugin_active = is_plugin_active( $plugin );
if ( isset( $upgrade_data->requires ) && ! is_wp_version_compatible( $upgrade_data->requires ) ) {
$result = new WP_Error(
'incompatible_wp_required_version',
sprintf(
/* translators: 1: Current WordPress version, 2: WordPress version required by the new plugin version. */
__( 'Your WordPress version is %1$s, however the new plugin version requires %2$s.' ),
$wp_version,
$upgrade_data->requires
)
);
$this->skin->before( $result );
$this->skin->error( $result );
$this->skin->after();
} elseif ( isset( $upgrade_data->requires_php ) && ! is_php_version_compatible( $upgrade_data->requires_php ) ) {
$result = new WP_Error(
'incompatible_php_required_version',
sprintf(
/* translators: 1: Current PHP version, 2: PHP version required by the new plugin version. */
__( 'The PHP version on your server is %1$s, however the new plugin version requires %2$s.' ),
PHP_VERSION,
$upgrade_data->requires_php
)
);
$this->skin->before( $result );
$this->skin->error( $result );
$this->skin->after();
} else {
add_filter( 'upgrader_source_selection', array( $this, 'check_package' ) );
$result = $this->run(
array(
'package' => $upgrade_data->package,
'destination' => WP_PLUGIN_DIR,
'clear_destination' => true,
'clear_working' => true,
'is_multi' => true,
'hook_extra' => array(
'plugin' => $plugin,
'temp_backup' => array(
'slug' => dirname( $plugin ),
'src' => WP_PLUGIN_DIR,
'dir' => 'plugins',
),
),
)
);
remove_filter( 'upgrader_source_selection', array( $this, 'check_package' ) );
}
$results[ $plugin ] = $result;
// Prevent credentials auth screen from displaying multiple times.
if ( false === $result ) {
break;
}
} // End foreach $plugins.
$this->maintenance_mode( false );
// Force refresh of plugin update information.
wp_clean_plugins_cache( $parsed_args['clear_update_cache'] );
/** This action is documented in wp-admin/includes/class-wp-upgrader.php */
do_action(
'upgrader_process_complete',
$this,
array(
'action' => 'update',
'type' => 'plugin',
'bulk' => true,
'plugins' => $plugins,
)
);
$this->skin->bulk_footer();
$this->skin->footer();
// Cleanup our hooks, in case something else does an upgrade on this connection.
remove_filter( 'upgrader_clear_destination', array( $this, 'delete_old_plugin' ) );
/*
* Ensure any future auto-update failures trigger a failure email by removing
* the last failure notification from the list when plugins update successfully.
*/
$past_failure_emails = get_option( 'auto_plugin_theme_update_emails', array() );
foreach ( $results as $plugin => $result ) {
// Maintain last failure notification when plugins failed to update manually.
if ( ! $result || is_wp_error( $result ) || ! isset( $past_failure_emails[ $plugin ] ) ) {
continue;
}
unset( $past_failure_emails[ $plugin ] );
}
update_option( 'auto_plugin_theme_update_emails', $past_failure_emails );
return $results;
}
/**
* Checks that the source package contains a valid plugin.
*
* Hooked to the 'upgrader_source_selection' filter by Plugin_Upgrader::install().
*
* @since 3.3.0
*
* @global WP_Filesystem_Base $wp_filesystem WordPress filesystem subclass.
*
* @param string $source The path to the downloaded package source.
* @return string|WP_Error The source as passed, or a WP_Error object on failure.
*/
public function check_package( $source ) {
global $wp_filesystem;
$wp_version = wp_get_wp_version();
$this->new_plugin_data = array();
if ( is_wp_error( $source ) ) {
return $source;
}
$working_directory = str_replace( $wp_filesystem->wp_content_dir(), trailingslashit( WP_CONTENT_DIR ), $source );
if ( ! is_dir( $working_directory ) ) { // Confidence check, if the above fails, let's not prevent installation.
return $source;
}
// Check that the folder contains at least 1 valid plugin.
$files = glob( $working_directory . '*.php' );
if ( $files ) {
foreach ( $files as $file ) {
$new_plugin_data = get_plugin_data( $file, false, false );
if ( ! empty( $new_plugin_data['Name'] ) ) {
$this->new_plugin_data = $new_plugin_data;
break;
}
}
}
if ( empty( $this->new_plugin_data ) ) {
return new WP_Error( 'incompatible_archive_no_plugins', $this->strings['incompatible_archive'], __( 'No valid plugins were found.' ) );
}
$requires_php = isset( $new_plugin_data['RequiresPHP'] ) ? $new_plugin_data['RequiresPHP'] : null;
$requires_wp = isset( $new_plugin_data['RequiresWP'] ) ? $new_plugin_data['RequiresWP'] : null;
if ( ! is_php_version_compatible( $requires_php ) ) {
$error = sprintf(
/* translators: 1: Current PHP version, 2: Version required by the uploaded plugin. */
__( 'The PHP version on your server is %1$s, however the uploaded plugin requires %2$s.' ),
PHP_VERSION,
$requires_php
);
return new WP_Error( 'incompatible_php_required_version', $this->strings['incompatible_archive'], $error );
}
if ( ! is_wp_version_compatible( $requires_wp ) ) {
$error = sprintf(
/* translators: 1: Current WordPress version, 2: Version required by the uploaded plugin. */
__( 'Your WordPress version is %1$s, however the uploaded plugin requires %2$s.' ),
$wp_version,
$requires_wp
);
return new WP_Error( 'incompatible_wp_required_version', $this->strings['incompatible_archive'], $error );
}
return $source;
}
/**
* Retrieves the path to the file that contains the plugin info.
*
* This isn't used internally in the class, but is called by the skins.
*
* @since 2.8.0
*
* @return string|false The full path to the main plugin file, or false.
*/
public function plugin_info() {
if ( ! is_array( $this->result ) ) {
return false;
}
if ( empty( $this->result['destination_name'] ) ) {
return false;
}
// Ensure to pass with leading slash.
$plugin = get_plugins( '/' . $this->result['destination_name'] );
if ( empty( $plugin ) ) {
return false;
}
// Assume the requested plugin is the first in the list.
$plugin_files = array_keys( $plugin );
return $this->result['destination_name'] . '/' . $plugin_files[0];
}
/**
* Deactivates a plugin before it is upgraded.
*
* Hooked to the 'upgrader_pre_install' filter by Plugin_Upgrader::upgrade().
*
* @since 2.8.0
* @since 4.1.0 Added a return value.
*
* @param bool|WP_Error $response The installation response before the installation has started.
* @param array $plugin Plugin package arguments.
* @return bool|WP_Error The original `$response` parameter or WP_Error.
*/
public function deactivate_plugin_before_upgrade( $response, $plugin ) {
if ( is_wp_error( $response ) ) { // Bypass.
return $response;
}
// When in cron (background updates) don't deactivate the plugin, as we require a browser to reactivate it.
if ( wp_doing_cron() ) {
return $response;
}
$plugin = isset( $plugin['plugin'] ) ? $plugin['plugin'] : '';
if ( empty( $plugin ) ) {
return new WP_Error( 'bad_request', $this->strings['bad_request'] );
}
if ( is_plugin_active( $plugin ) ) {
// Deactivate the plugin silently, Prevent deactivation hooks from running.
deactivate_plugins( $plugin, true );
}
return $response;
}
/**
* Turns on maintenance mode before attempting to background update an active plugin.
*
* Hooked to the 'upgrader_pre_install' filter by Plugin_Upgrader::upgrade().
*
* @since 5.4.0
*
* @param bool|WP_Error $response The installation response before the installation has started.
* @param array $plugin Plugin package arguments.
* @return bool|WP_Error The original `$response` parameter or WP_Error.
*/
public function active_before( $response, $plugin ) {
if ( is_wp_error( $response ) ) {
return $response;
}
// Only enable maintenance mode when in cron (background update).
if ( ! wp_doing_cron() ) {
return $response;
}
$plugin = isset( $plugin['plugin'] ) ? $plugin['plugin'] : '';
// Only run if plugin is active.
if ( ! is_plugin_active( $plugin ) ) {
return $response;
}
// Change to maintenance mode. Bulk edit handles this separately.
if ( ! $this->bulk ) {
$this->maintenance_mode( true );
}
return $response;
}
/**
* Turns off maintenance mode after upgrading an active plugin.
*
* Hooked to the 'upgrader_post_install' filter by Plugin_Upgrader::upgrade().
*
* @since 5.4.0
*
* @param bool|WP_Error $response The installation response after the installation has finished.
* @param array $plugin Plugin package arguments.
* @return bool|WP_Error The original `$response` parameter or WP_Error.
*/
public function active_after( $response, $plugin ) {
if ( is_wp_error( $response ) ) {
return $response;
}
// Only disable maintenance mode when in cron (background update).
if ( ! wp_doing_cron() ) {
return $response;
}
$plugin = isset( $plugin['plugin'] ) ? $plugin['plugin'] : '';
// Only run if plugin is active.
if ( ! is_plugin_active( $plugin ) ) {
return $response;
}
// Time to remove maintenance mode. Bulk edit handles this separately.
if ( ! $this->bulk ) {
$this->maintenance_mode( false );
}
return $response;
}
/**
* Deletes the old plugin during an upgrade.
*
* Hooked to the 'upgrader_clear_destination' filter by
* Plugin_Upgrader::upgrade() and Plugin_Upgrader::bulk_upgrade().
*
* @since 2.8.0
*
* @global WP_Filesystem_Base $wp_filesystem WordPress filesystem subclass.
*
* @param bool|WP_Error $removed Whether the destination was cleared.
* True on success, WP_Error on failure.
* @param string $local_destination The local package destination.
* @param string $remote_destination The remote package destination.
* @param array $plugin Extra arguments passed to hooked filters.
* @return bool|WP_Error
*/
public function delete_old_plugin( $removed, $local_destination, $remote_destination, $plugin ) {
global $wp_filesystem;
if ( is_wp_error( $removed ) ) {
return $removed; // Pass errors through.
}
$plugin = isset( $plugin['plugin'] ) ? $plugin['plugin'] : '';
if ( empty( $plugin ) ) {
return new WP_Error( 'bad_request', $this->strings['bad_request'] );
}
$plugins_dir = $wp_filesystem->wp_plugins_dir();
$this_plugin_dir = trailingslashit( dirname( $plugins_dir . $plugin ) );
if ( ! $wp_filesystem->exists( $this_plugin_dir ) ) { // If it's already vanished.
return $removed;
}
/*
* If plugin is in its own directory, recursively delete the directory.
* Base check on if plugin includes directory separator AND that it's not the root plugin folder.
*/
if ( strpos( $plugin, '/' ) && $this_plugin_dir !== $plugins_dir ) {
$deleted = $wp_filesystem->delete( $this_plugin_dir, true );
} else {
$deleted = $wp_filesystem->delete( $plugins_dir . $plugin );
}
if ( ! $deleted ) {
return new WP_Error( 'remove_old_failed', $this->strings['remove_old_failed'] );
}
return true;
}
}
```
[View all references](https://developer.wordpress.org/reference/files/wp-admin/includes/class-plugin-upgrader.php/)
[View on Trac](https://core.trac.wordpress.org/browser/tags/6.9.4/src/wp-admin/includes/class-plugin-upgrader.php#L21)
[View on GitHub](https://github.com/WordPress/wordpress-develop/blob/6.9.4/src/wp-admin/includes/class-plugin-upgrader.php#L21-L710)
## [Related](https://developer.wordpress.org/reference/classes/plugin_upgrader/?output_format=md#related)
| Uses | Description |
| [WP_Upgrader](https://developer.wordpress.org/reference/classes/wp_upgrader/)`wp-admin/includes/class-wp-upgrader.php` | |
## [Changelog](https://developer.wordpress.org/reference/classes/plugin_upgrader/?output_format=md#changelog)
| Version | Description |
| [4.6.0](https://developer.wordpress.org/reference/since/4.6.0/) | Moved to its own file from wp-admin/includes/class-wp-upgrader.php. |
| [2.8.0](https://developer.wordpress.org/reference/since/2.8.0/) | Introduced. |
## User Contributed Notes
You must [log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fdeveloper.wordpress.org%2Freference%2Fclasses%2Fplugin_upgrader%2F)
before being able to contribute a note or feedback.