Theme_Upgrader::upgrade( string $theme, array $args = array() ): bool|WP_Error

Compatibility

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

Parameters

$themestring

The theme slug.

$argsarrayoptional

Other arguments for upgrading a theme. Default empty array.Default: array()

• $clear_update_cachebooldefault: true

  Whether to clear the update cache if successful.

Return value

bool|WP_Error

True if the upgrade was successful, false or a WP_Error object otherwise.

Performance profile

How much work a call to Theme_Upgrader::upgrade() 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

Moderate

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

Scaling

Constant

No loop in the body: the same number of instructions runs whatever you pass in.

Instructions

34–130

Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 147.

Plugin surface

None

Nothing here hands control to plugin code.

Called by

0

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

What it touches

• transienttransientget_site_transient()called directly
• optionoption read or writeget_option()called directly
• hookthird-party callbacksapply_filters()one call below Theme_Upgrader::upgrade()
• cacheobject cachewp_cache_get()one call below Theme_Upgrader::upgrade()
• serializeserialisationmaybe_unserialize()one call below Theme_Upgrader::upgrade()

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

What one call costs · 9 distinct outcomes

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

Uses · 14

• wp_parse_args()Merges user defined arguments into defaults array.
• get_site_transient()Retrieves the value of a site transient.
• add_filter()Adds a callback function to a filter hook.
• add_action()Adds a callback function to an action hook.
• get_theme_root()Retrieves path to themes directory.
• remove_action()Removes a callback function from an action hook.
• remove_filter()Removes a callback function from a filter hook.
• is_wp_error()Checks whether the given variable is a WordPress Error.
• wp_clean_themes_cache()Clears the cache held by get_theme_roots() and WP_Theme.
• get_option()Retrieves an option value based on an option name.
• update_option()Updates the value of an option that was already added.
• Theme_Upgrader::init()

Source code

View on Trac ↗View on GitHub ↗

295	public function upgrade( $theme, $args = array() ) {296		$defaults    = array(297			'clear_update_cache' => true,298		);299		$parsed_args = wp_parse_args( $args, $defaults );300 301		$this->init();302		$this->upgrade_strings();303 304		// Is an update available?305		$current = get_site_transient( 'update_themes' );306		if ( ! isset( $current->response[ $theme ] ) ) {307			$this->skin->before();308			$this->skin->set_result( false );309			$this->skin->error( 'up_to_date' );310			$this->skin->after();311			return false;312		}313 314		$r = $current->response[ $theme ];315 316		add_filter( 'upgrader_pre_install', array( $this, 'current_before' ), 10, 2 );317		add_filter( 'upgrader_post_install', array( $this, 'current_after' ), 10, 2 );318		add_filter( 'upgrader_clear_destination', array( $this, 'delete_old_theme' ), 10, 4 );319		if ( $parsed_args['clear_update_cache'] ) {320			// Clear cache so wp_update_themes() knows about the new theme.321			add_action( 'upgrader_process_complete', 'wp_clean_themes_cache', 9, 0 );322		}323 324		$this->run(325			array(326				'package'           => $r['package'],327				'destination'       => get_theme_root( $theme ),328				'clear_destination' => true,329				'clear_working'     => true,330				'hook_extra'        => array(331					'theme'       => $theme,332					'type'        => 'theme',333					'action'      => 'update',334					'temp_backup' => array(335						'slug' => $theme,336						'src'  => get_theme_root( $theme ),337						'dir'  => 'themes',338					),339				),340			)341		);342 343		remove_action( 'upgrader_process_complete', 'wp_clean_themes_cache', 9 );344		remove_filter( 'upgrader_pre_install', array( $this, 'current_before' ) );345		remove_filter( 'upgrader_post_install', array( $this, 'current_after' ) );346		remove_filter( 'upgrader_clear_destination', array( $this, 'delete_old_theme' ) );347 348		if ( ! $this->result || is_wp_error( $this->result ) ) {349			return $this->result;350		}351 352		wp_clean_themes_cache( $parsed_args['clear_update_cache'] );353 354		/*355		 * Ensure any future auto-update failures trigger a failure email by removing356		 * the last failure notification from the list when themes update successfully.357		 */358		$past_failure_emails = get_option( 'auto_plugin_theme_update_emails', array() );359 360		if ( isset( $past_failure_emails[ $theme ] ) ) {361			unset( $past_failure_emails[ $theme ] );362			update_option( 'auto_plugin_theme_update_emails', $past_failure_emails );363		}364 365		return true;366	}

Changelog

Introduced in 2.8.0. 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 6.8.8 tag, from src/wp-admin/includes/class-theme-upgrader.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.

Corrections

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