WordPress 4.4
[autoinstalls/wordpress.git] / wp-includes / class-wp-customize-setting.php
index c4cff0e29bc5a7dcd62d6b17e91a0e24c5af5025..434dec7c069e60944bec1f0788f854dd61a229cb 100644 (file)
 <?php
 /**
- * Customize Setting Class
+ * WordPress Customize Setting classes
  *
  * @package WordPress
  * @subpackage Customize
  * @since 3.4.0
  */
 
+/**
+ * Customize Setting class.
+ *
+ * Handles saving and sanitizing of settings.
+ *
+ * @since 3.4.0
+ *
+ * @see WP_Customize_Manager
+ */
 class WP_Customize_Setting {
+       /**
+        * @access public
+        * @var WP_Customize_Manager
+        */
        public $manager;
+
+       /**
+        * Unique string identifier for the setting.
+        *
+        * @access public
+        * @var string
+        */
        public $id;
 
-       public $type            = 'theme_mod';
-       public $capability      = 'edit_theme_options';
+       /**
+        * @access public
+        * @var string
+        */
+       public $type = 'theme_mod';
+
+       /**
+        * Capability required to edit this setting.
+        *
+        * @var string
+        */
+       public $capability = 'edit_theme_options';
+
+       /**
+        * Feature a theme is required to support to enable this setting.
+        *
+        * @access public
+        * @var string
+        */
        public $theme_supports  = '';
        public $default         = '';
        public $transport       = 'refresh';
 
+       /**
+        * Server-side sanitization callback for the setting's value.
+        *
+        * @var callback
+        */
        public $sanitize_callback    = '';
        public $sanitize_js_callback = '';
 
+       /**
+        * Whether or not the setting is initially dirty when created.
+        *
+        * This is used to ensure that a setting will be sent from the pane to the
+        * preview when loading the Customizer. Normally a setting only is synced to
+        * the preview if it has been changed. This allows the setting to be sent
+        * from the start.
+        *
+        * @since 4.2.0
+        * @access public
+        * @var bool
+        */
+       public $dirty = false;
+
+       /**
+        * @var array
+        */
        protected $id_data = array();
-       private $_post_value; // Cached, sanitized $_POST value.
+
+       /**
+        * Whether or not preview() was called.
+        *
+        * @since 4.4.0
+        * @access protected
+        * @var bool
+        */
+       protected $is_previewed = false;
+
+       /**
+        * Cache of multidimensional values to improve performance.
+        *
+        * @since 4.4.0
+        * @access protected
+        * @var array
+        * @static
+        */
+       protected static $aggregated_multidimensionals = array();
+
+       /**
+        * Whether the multidimensional setting is aggregated.
+        *
+        * @since 4.4.0
+        * @access protected
+        * @var bool
+        */
+       protected $is_multidimensional_aggregated = false;
 
        /**
         * Constructor.
         *
+        * Any supplied $args override class property defaults.
+        *
         * @since 3.4.0
         *
-        * @param string $id An specific ID of the setting. Can be a
-        *                   theme mod or option name.
-        * @param array $args Setting arguments.
+        * @param WP_Customize_Manager $manager
+        * @param string               $id      An specific ID of the setting. Can be a
+        *                                      theme mod or option name.
+        * @param array                $args    Setting arguments.
         */
-       function __construct( $manager, $id, $args = array() ) {
-               $keys = array_keys( get_class_vars( __CLASS__ ) );
+       public function __construct( $manager, $id, $args = array() ) {
+               $keys = array_keys( get_object_vars( $this ) );
                foreach ( $keys as $key ) {
-                       if ( isset( $args[ $key ] ) )
+                       if ( isset( $args[ $key ] ) ) {
                                $this->$key = $args[ $key ];
+                       }
                }
 
                $this->manager = $manager;
                $this->id = $id;
 
                // Parse the ID for array keys.
-               $this->id_data[ 'keys' ] = preg_split( '/\[/', str_replace( ']', '', $this->id ) );
-               $this->id_data[ 'base' ] = array_shift( $this->id_data[ 'keys' ] );
+               $this->id_data['keys'] = preg_split( '/\[/', str_replace( ']', '', $this->id ) );
+               $this->id_data['base'] = array_shift( $this->id_data['keys'] );
 
                // Rebuild the ID.
                $this->id = $this->id_data[ 'base' ];
-               if ( ! empty( $this->id_data[ 'keys' ] ) )
-                       $this->id .= '[' . implode( '][', $this->id_data[ 'keys' ] ) . ']';
+               if ( ! empty( $this->id_data[ 'keys' ] ) ) {
+                       $this->id .= '[' . implode( '][', $this->id_data['keys'] ) . ']';
+               }
 
-               if ( $this->sanitize_callback )
+               if ( $this->sanitize_callback ) {
                        add_filter( "customize_sanitize_{$this->id}", $this->sanitize_callback, 10, 2 );
-
-               if ( $this->sanitize_js_callback )
+               }
+               if ( $this->sanitize_js_callback ) {
                        add_filter( "customize_sanitize_js_{$this->id}", $this->sanitize_js_callback, 10, 2 );
+               }
+
+               if ( 'option' === $this->type || 'theme_mod' === $this->type ) {
+                       // Other setting types can opt-in to aggregate multidimensional explicitly.
+                       $this->aggregate_multidimensional();
+
+                       // Allow option settings to indicate whether they should be autoloaded.
+                       if ( 'option' === $this->type && isset( $args['autoload'] ) ) {
+                               self::$aggregated_multidimensionals[ $this->type ][ $this->id_data['base'] ]['autoload'] = $args['autoload'];
+                       }
+               }
+       }
 
-               return $this;
+       /**
+        * Get parsed ID data for multidimensional setting.
+        *
+        * @since 4.4.0
+        * @access public
+        *
+        * @return array {
+        *     ID data for multidimensional setting.
+        *
+        *     @type string $base ID base
+        *     @type array  $keys Keys for multidimensional array.
+        * }
+        */
+       final public function id_data() {
+               return $this->id_data;
        }
 
        /**
-        * Handle previewing the setting.
+        * Set up the setting for aggregated multidimensional values.
+        *
+        * When a multidimensional setting gets aggregated, all of its preview and update
+        * calls get combined into one call, greatly improving performance.
+        *
+        * @since 4.4.0
+        * @access protected
+        */
+       protected function aggregate_multidimensional() {
+               $id_base = $this->id_data['base'];
+               if ( ! isset( self::$aggregated_multidimensionals[ $this->type ] ) ) {
+                       self::$aggregated_multidimensionals[ $this->type ] = array();
+               }
+               if ( ! isset( self::$aggregated_multidimensionals[ $this->type ][ $id_base ] ) ) {
+                       self::$aggregated_multidimensionals[ $this->type ][ $id_base ] = array(
+                               'previewed_instances'       => array(), // Calling preview() will add the $setting to the array.
+                               'preview_applied_instances' => array(), // Flags for which settings have had their values applied.
+                               'root_value'                => $this->get_root_value( array() ), // Root value for initial state, manipulated by preview and update calls.
+                       );
+               }
+
+               if ( ! empty( $this->id_data['keys'] ) ) {
+                       // Note the preview-applied flag is cleared at priority 9 to ensure it is cleared before a deferred-preview runs.
+                       add_action( "customize_post_value_set_{$this->id}", array( $this, '_clear_aggregated_multidimensional_preview_applied_flag' ), 9 );
+                       $this->is_multidimensional_aggregated = true;
+               }
+       }
+
+       /**
+        * The ID for the current blog when the preview() method was called.
+        *
+        * @since 4.2.0
+        * @access protected
+        * @var int
+        */
+       protected $_previewed_blog_id;
+
+       /**
+        * Return true if the current blog is not the same as the previewed blog.
+        *
+        * @since 4.2.0
+        * @access public
+        *
+        * @return bool If preview() has been called.
+        */
+       public function is_current_blog_previewed() {
+               if ( ! isset( $this->_previewed_blog_id ) ) {
+                       return false;
+               }
+               return ( get_current_blog_id() === $this->_previewed_blog_id );
+       }
+
+       /**
+        * Original non-previewed value stored by the preview method.
+        *
+        * @see WP_Customize_Setting::preview()
+        * @since 4.1.1
+        * @var mixed
+        */
+       protected $_original_value;
+
+       /**
+        * Add filters to supply the setting's value when accessed.
+        *
+        * If the setting already has a pre-existing value and there is no incoming
+        * post value for the setting, then this method will short-circuit since
+        * there is no change to preview.
         *
         * @since 3.4.0
+        * @since 4.4.0 Added boolean return value.
+        * @access public
+        *
+        * @return bool False when preview short-circuits due no change needing to be previewed.
         */
        public function preview() {
-               switch( $this->type ) {
+               if ( ! isset( $this->_previewed_blog_id ) ) {
+                       $this->_previewed_blog_id = get_current_blog_id();
+               }
+
+               // Prevent re-previewing an already-previewed setting.
+               if ( $this->is_previewed ) {
+                       return true;
+               }
+
+               $id_base = $this->id_data['base'];
+               $is_multidimensional = ! empty( $this->id_data['keys'] );
+               $multidimensional_filter = array( $this, '_multidimensional_preview_filter' );
+
+               /*
+                * Check if the setting has a pre-existing value (an isset check),
+                * and if doesn't have any incoming post value. If both checks are true,
+                * then the preview short-circuits because there is nothing that needs
+                * to be previewed.
+                */
+               $undefined = new stdClass();
+               $needs_preview = ( $undefined !== $this->post_value( $undefined ) );
+               $value = null;
+
+               // Since no post value was defined, check if we have an initial value set.
+               if ( ! $needs_preview ) {
+                       if ( $this->is_multidimensional_aggregated ) {
+                               $root = self::$aggregated_multidimensionals[ $this->type ][ $id_base ]['root_value'];
+                               $value = $this->multidimensional_get( $root, $this->id_data['keys'], $undefined );
+                       } else {
+                               $default = $this->default;
+                               $this->default = $undefined; // Temporarily set default to undefined so we can detect if existing value is set.
+                               $value = $this->value();
+                               $this->default = $default;
+                       }
+                       $needs_preview = ( $undefined === $value ); // Because the default needs to be supplied.
+               }
+
+               // If the setting does not need previewing now, defer to when it has a value to preview.
+               if ( ! $needs_preview ) {
+                       if ( ! has_action( "customize_post_value_set_{$this->id}", array( $this, 'preview' ) ) ) {
+                               add_action( "customize_post_value_set_{$this->id}", array( $this, 'preview' ) );
+                       }
+                       return false;
+               }
+
+               switch ( $this->type ) {
                        case 'theme_mod' :
-                               add_filter( 'theme_mod_' . $this->id_data[ 'base' ], array( $this, '_preview_filter' ) );
+                               if ( ! $is_multidimensional ) {
+                                       add_filter( "theme_mod_{$id_base}", array( $this, '_preview_filter' ) );
+                               } else {
+                                       if ( empty( self::$aggregated_multidimensionals[ $this->type ][ $id_base ]['previewed_instances'] ) ) {
+                                               // Only add this filter once for this ID base.
+                                               add_filter( "theme_mod_{$id_base}", $multidimensional_filter );
+                                       }
+                                       self::$aggregated_multidimensionals[ $this->type ][ $id_base ]['previewed_instances'][ $this->id ] = $this;
+                               }
                                break;
                        case 'option' :
-                               if ( empty( $this->id_data[ 'keys' ] ) )
-                                       add_filter( 'pre_option_' . $this->id_data[ 'base' ], array( $this, '_preview_filter' ) );
-                               else {
-                                       add_filter( 'option_' . $this->id_data[ 'base' ], array( $this, '_preview_filter' ) );
-                                       add_filter( 'default_option_' . $this->id_data[ 'base' ], array( $this, '_preview_filter' ) );
+                               if ( ! $is_multidimensional ) {
+                                       add_filter( "pre_option_{$id_base}", array( $this, '_preview_filter' ) );
+                               } else {
+                                       if ( empty( self::$aggregated_multidimensionals[ $this->type ][ $id_base ]['previewed_instances'] ) ) {
+                                               // Only add these filters once for this ID base.
+                                               add_filter( "option_{$id_base}", $multidimensional_filter );
+                                               add_filter( "default_option_{$id_base}", $multidimensional_filter );
+                                       }
+                                       self::$aggregated_multidimensionals[ $this->type ][ $id_base ]['previewed_instances'][ $this->id ] = $this;
                                }
                                break;
                        default :
-                               do_action( 'customize_preview_' . $this->id );
+
+                               /**
+                                * Fires when the {@see WP_Customize_Setting::preview()} method is called for settings
+                                * not handled as theme_mods or options.
+                                *
+                                * The dynamic portion of the hook name, `$this->id`, refers to the setting ID.
+                                *
+                                * @since 3.4.0
+                                *
+                                * @param WP_Customize_Setting $this {@see WP_Customize_Setting} instance.
+                                */
+                               do_action( "customize_preview_{$this->id}", $this );
+
+                               /**
+                                * Fires when the {@see WP_Customize_Setting::preview()} method is called for settings
+                                * not handled as theme_mods or options.
+                                *
+                                * The dynamic portion of the hook name, `$this->type`, refers to the setting type.
+                                *
+                                * @since 4.1.0
+                                *
+                                * @param WP_Customize_Setting $this {@see WP_Customize_Setting} instance.
+                                */
+                               do_action( "customize_preview_{$this->type}", $this );
                }
+
+               $this->is_previewed = true;
+
+               return true;
        }
 
        /**
-        * Callback function to filter the theme mods and options.
+        * Clear out the previewed-applied flag for a multidimensional-aggregated value whenever its post value is updated.
+        *
+        * This ensures that the new value will get sanitized and used the next time
+        * that <code>WP_Customize_Setting::_multidimensional_preview_filter()</code>
+        * is called for this setting.
+        *
+        * @since 4.4.0
+        * @access private
+        * @see WP_Customize_Manager::set_post_value()
+        * @see WP_Customize_Setting::_multidimensional_preview_filter()
+        */
+       final public function _clear_aggregated_multidimensional_preview_applied_flag() {
+               unset( self::$aggregated_multidimensionals[ $this->type ][ $this->id_data['base'] ]['preview_applied_instances'][ $this->id ] );
+       }
+
+       /**
+        * Callback function to filter non-multidimensional theme mods and options.
+        *
+        * If switch_to_blog() was called after the preview() method, and the current
+        * blog is now not the same blog, then this method does a no-op and returns
+        * the original value.
         *
         * @since 3.4.0
         *
-        * @param mixed Old value.
+        * @param mixed $original Old value.
         * @return mixed New or old value.
         */
        public function _preview_filter( $original ) {
-               return $this->multidimensional_replace( $original, $this->id_data[ 'keys' ], $this->post_value() );
+               if ( ! $this->is_current_blog_previewed() ) {
+                       return $original;
+               }
+
+               $undefined = new stdClass(); // Symbol hack.
+               $post_value = $this->post_value( $undefined );
+               if ( $undefined !== $post_value ) {
+                       $value = $post_value;
+               } else {
+                       /*
+                        * Note that we don't use $original here because preview() will
+                        * not add the filter in the first place if it has an initial value
+                        * and there is no post value.
+                        */
+                       $value = $this->default;
+               }
+               return $value;
        }
 
        /**
-        * Set the value of the parameter for a specific theme.
+        * Callback function to filter multidimensional theme mods and options.
+        *
+        * For all multidimensional settings of a given type, the preview filter for
+        * the first setting previewed will be used to apply the values for the others.
+        *
+        * @since 4.4.0
+        * @access private
+        *
+        * @see WP_Customize_Setting::$aggregated_multidimensionals
+        * @param mixed $original Original root value.
+        * @return mixed New or old value.
+        */
+       final public function _multidimensional_preview_filter( $original ) {
+               if ( ! $this->is_current_blog_previewed() ) {
+                       return $original;
+               }
+
+               $id_base = $this->id_data['base'];
+
+               // If no settings have been previewed yet (which should not be the case, since $this is), just pass through the original value.
+               if ( empty( self::$aggregated_multidimensionals[ $this->type ][ $id_base ]['previewed_instances'] ) ) {
+                       return $original;
+               }
+
+               foreach ( self::$aggregated_multidimensionals[ $this->type ][ $id_base ]['previewed_instances'] as $previewed_setting ) {
+                       // Skip applying previewed value for any settings that have already been applied.
+                       if ( ! empty( self::$aggregated_multidimensionals[ $this->type ][ $id_base ]['preview_applied_instances'][ $previewed_setting->id ] ) ) {
+                               continue;
+                       }
+
+                       // Do the replacements of the posted/default sub value into the root value.
+                       $value = $previewed_setting->post_value( $previewed_setting->default );
+                       $root = self::$aggregated_multidimensionals[ $previewed_setting->type ][ $id_base ]['root_value'];
+                       $root = $previewed_setting->multidimensional_replace( $root, $previewed_setting->id_data['keys'], $value );
+                       self::$aggregated_multidimensionals[ $previewed_setting->type ][ $id_base ]['root_value'] = $root;
+
+                       // Mark this setting having been applied so that it will be skipped when the filter is called again.
+                       self::$aggregated_multidimensionals[ $previewed_setting->type ][ $id_base ]['preview_applied_instances'][ $previewed_setting->id ] = true;
+               }
+
+               return self::$aggregated_multidimensionals[ $this->type ][ $id_base ]['root_value'];
+       }
+
+       /**
+        * Check user capabilities and theme supports, and then save
+        * the value of the setting.
         *
         * @since 3.4.0
         *
-        * @return bool False if cap check fails or value isn't set.
+        * @return false|void False if cap check fails or value isn't set.
         */
-       public final function save() {
+       final public function save() {
                $value = $this->post_value();
 
                if ( ! $this->check_capabilities() || ! isset( $value ) )
                        return false;
 
-               do_action( 'customize_save_' . $this->id_data[ 'base' ] );
+               /**
+                * Fires when the WP_Customize_Setting::save() method is called.
+                *
+                * The dynamic portion of the hook name, `$this->id_data['base']` refers to
+                * the base slug of the setting name.
+                *
+                * @since 3.4.0
+                *
+                * @param WP_Customize_Setting $this {@see WP_Customize_Setting} instance.
+                */
+               do_action( 'customize_save_' . $this->id_data[ 'base' ], $this );
 
                $this->update( $value );
        }
 
        /**
-        * Fetches, validates, and sanitizes the $_POST value.
+        * Fetch and sanitize the $_POST value for the setting.
         *
         * @since 3.4.0
         *
-        * @param $default mixed A default value which is used as a fallback. Default is null.
-        * @return mixed Either the default value on failure or sanitized value.
+        * @param mixed $default A default value which is used as a fallback. Default is null.
+        * @return mixed The default value on failure, otherwise the sanitized value.
         */
-       public final function post_value( $default = null ) {
-               if ( isset( $this->_post_value ) )
-                       return $this->_post_value;
-
-               $result = $this->manager->post_value( $this );
-
-               if ( isset( $result ) )
-                       return $this->_post_value = $result;
-               else
-                       return $default;
+       final public function post_value( $default = null ) {
+               return $this->manager->post_value( $this, $default );
        }
 
        /**
@@ -138,111 +492,191 @@ class WP_Customize_Setting {
         *
         * @since 3.4.0
         *
-        * @param $value mixed The value to sanitize.
-        * @return mixed Null if an input isn't valid, otherwise the sanitized value.
+        * @param string|array $value The value to sanitize.
+        * @return string|array|null Null if an input isn't valid, otherwise the sanitized value.
         */
        public function sanitize( $value ) {
-               $value = stripslashes_deep( $value );
+               $value = wp_unslash( $value );
+
+               /**
+                * Filter a Customize setting value in un-slashed form.
+                *
+                * @since 3.4.0
+                *
+                * @param mixed                $value Value of the setting.
+                * @param WP_Customize_Setting $this  WP_Customize_Setting instance.
+                */
                return apply_filters( "customize_sanitize_{$this->id}", $value, $this );
        }
 
        /**
-        * Set the value of the parameter for a specific theme.
+        * Get the root value for a setting, especially for multidimensional ones.
         *
-        * @since 3.4.0
+        * @since 4.4.0
+        * @access protected
         *
-        * @param $value mixed The value to update.
-        * @return mixed The result of saving the value.
+        * @param mixed $default Value to return if root does not exist.
+        * @return mixed
         */
-       protected function update( $value ) {
-               switch( $this->type ) {
-                       case 'theme_mod' :
-                               return $this->_update_theme_mod( $value );
-                               break;
-                       case 'option' :
-                               return $this->_update_option( $value );
-                               break;
-                       default :
-                               return do_action( 'customize_update_' . $this->type, $value );
+       protected function get_root_value( $default = null ) {
+               $id_base = $this->id_data['base'];
+               if ( 'option' === $this->type ) {
+                       return get_option( $id_base, $default );
+               } else if ( 'theme_mod' ) {
+                       return get_theme_mod( $id_base, $default );
+               } else {
+                       /*
+                        * Any WP_Customize_Setting subclass implementing aggregate multidimensional
+                        * will need to override this method to obtain the data from the appropriate
+                        * location.
+                        */
+                       return $default;
                }
        }
 
        /**
-        * Update the theme mod from the value of the parameter.
+        * Set the root value for a setting, especially for multidimensional ones.
         *
-        * @since 3.4.0
+        * @since 4.4.0
+        * @access protected
         *
-        * @param $value mixed The value to update.
-        * @return mixed The result of saving the value.
+        * @param mixed $value Value to set as root of multidimensional setting.
+        * @return bool Whether the multidimensional root was updated successfully.
         */
-       protected function _update_theme_mod( $value ) {
-               // Handle non-array theme mod.
-               if ( empty( $this->id_data[ 'keys' ] ) )
-                       return set_theme_mod( $this->id_data[ 'base' ], $value );
-
-               // Handle array-based theme mod.
-               $mods = get_theme_mod( $this->id_data[ 'base' ] );
-               $mods = $this->multidimensional_replace( $mods, $this->id_data[ 'keys' ], $value );
-               if ( isset( $mods ) )
-                       return set_theme_mod( $this->id_data[ 'base' ], $mods );
+       protected function set_root_value( $value ) {
+               $id_base = $this->id_data['base'];
+               if ( 'option' === $this->type ) {
+                       $autoload = true;
+                       if ( isset( self::$aggregated_multidimensionals[ $this->type ][ $this->id_data['base'] ]['autoload'] ) ) {
+                               $autoload = self::$aggregated_multidimensionals[ $this->type ][ $this->id_data['base'] ]['autoload'];
+                       }
+                       return update_option( $id_base, $value, $autoload );
+               } else if ( 'theme_mod' ) {
+                       set_theme_mod( $id_base, $value );
+                       return true;
+               } else {
+                       /*
+                        * Any WP_Customize_Setting subclass implementing aggregate multidimensional
+                        * will need to override this method to obtain the data from the appropriate
+                        * location.
+                        */
+                       return false;
+               }
        }
 
        /**
-        * Update the theme mod from the value of the parameter.
+        * Save the value of the setting, using the related API.
         *
         * @since 3.4.0
         *
-        * @param $value mixed The value to update.
-        * @return mixed The result of saving the value.
+        * @param mixed $value The value to update.
+        * @return bool The result of saving the value.
         */
-       protected function _update_option( $value ) {
-               // Handle non-array option.
-               if ( empty( $this->id_data[ 'keys' ] ) )
-                       return update_option( $this->id_data[ 'base' ], $value );
+       protected function update( $value ) {
+               $id_base = $this->id_data['base'];
+               if ( 'option' === $this->type || 'theme_mod' === $this->type ) {
+                       if ( ! $this->is_multidimensional_aggregated ) {
+                               return $this->set_root_value( $value );
+                       } else {
+                               $root = self::$aggregated_multidimensionals[ $this->type ][ $id_base ]['root_value'];
+                               $root = $this->multidimensional_replace( $root, $this->id_data['keys'], $value );
+                               self::$aggregated_multidimensionals[ $this->type ][ $id_base ]['root_value'] = $root;
+                               return $this->set_root_value( $root );
+                       }
+               } else {
+                       /**
+                        * Fires when the {@see WP_Customize_Setting::update()} method is called for settings
+                        * not handled as theme_mods or options.
+                        *
+                        * The dynamic portion of the hook name, `$this->type`, refers to the type of setting.
+                        *
+                        * @since 3.4.0
+                        *
+                        * @param mixed                $value Value of the setting.
+                        * @param WP_Customize_Setting $this  WP_Customize_Setting instance.
+                        */
+                       do_action( "customize_update_{$this->type}", $value, $this );
+
+                       return has_action( "customize_update_{$this->type}" );
+               }
+       }
 
-               // Handle array-based options.
-               $options = get_option( $this->id_data[ 'base' ] );
-               $options = $this->multidimensional_replace( $options, $this->id_data[ 'keys' ], $value );
-               if ( isset( $options ) )
-                       return update_option( $this->id_data[ 'base' ], $options );
+       /**
+        * Deprecated method.
+        *
+        * @since 3.4.0
+        * @deprecated 4.4.0 Deprecated in favor of update() method.
+        */
+       protected function _update_theme_mod() {
+               _deprecated_function( __METHOD__, '4.4.0', __CLASS__ . '::update()' );
        }
 
        /**
-        * Fetch the value of the parameter for a specific theme.
+        * Deprecated method.
         *
         * @since 3.4.0
+        * @deprecated 4.4.0 Deprecated in favor of update() method.
+        */
+       protected function _update_option() {
+               _deprecated_function( __METHOD__, '4.4.0', __CLASS__ . '::update()' );
+       }
+
+       /**
+        * Fetch the value of the setting.
         *
-        * @return mixed The requested value.
+        * @since 3.4.0
+        *
+        * @return mixed The value.
         */
        public function value() {
-               switch( $this->type ) {
-                       case 'theme_mod' :
-                               $function = 'get_theme_mod';
-                               break;
-                       case 'option' :
-                               $function = 'get_option';
-                               break;
-                       default :
-                               return apply_filters( 'customize_value_' . $this->id_data[ 'base' ], $this->default );
+               $id_base = $this->id_data['base'];
+               $is_core_type = ( 'option' === $this->type || 'theme_mod' === $this->type );
+
+               if ( ! $is_core_type && ! $this->is_multidimensional_aggregated ) {
+                       $value = $this->get_root_value( $this->default );
+
+                       /**
+                        * Filter a Customize setting value not handled as a theme_mod or option.
+                        *
+                        * The dynamic portion of the hook name, `$this->id_date['base']`, refers to
+                        * the base slug of the setting name.
+                        *
+                        * For settings handled as theme_mods or options, see those corresponding
+                        * functions for available hooks.
+                        *
+                        * @since 3.4.0
+                        *
+                        * @param mixed $default The setting default value. Default empty.
+                        */
+                       $value = apply_filters( "customize_value_{$id_base}", $value );
+               } else if ( $this->is_multidimensional_aggregated ) {
+                       $root_value = self::$aggregated_multidimensionals[ $this->type ][ $id_base ]['root_value'];
+                       $value = $this->multidimensional_get( $root_value, $this->id_data['keys'], $this->default );
+               } else {
+                       $value = $this->get_root_value( $this->default );
                }
-
-               // Handle non-array value
-               if ( empty( $this->id_data[ 'keys' ] ) )
-                       return $function( $this->id_data[ 'base' ], $this->default );
-
-               // Handle array-based value
-               $values = $function( $this->id_data[ 'base' ] );
-               return $this->multidimensional_get( $values, $this->id_data[ 'keys' ], $this->default );
+               return $value;
        }
 
        /**
-        * Escape the parameter's value for use in JavaScript.
+        * Sanitize the setting's value for use in JavaScript.
         *
         * @since 3.4.0
         *
         * @return mixed The requested escaped value.
         */
        public function js_value() {
+
+               /**
+                * Filter a Customize setting value for use in JavaScript.
+                *
+                * The dynamic portion of the hook name, `$this->id`, refers to the setting ID.
+                *
+                * @since 3.4.0
+                *
+                * @param mixed                $value The setting value.
+                * @param WP_Customize_Setting $this  {@see WP_Customize_Setting} instance.
+                */
                $value = apply_filters( "customize_sanitize_js_{$this->id}", $this->value(), $this );
 
                if ( is_string( $value ) )
@@ -252,13 +686,13 @@ class WP_Customize_Setting {
        }
 
        /**
-        * Check if the theme supports the setting and check user capabilities.
+        * Validate user capabilities whether the theme supports the setting.
         *
         * @since 3.4.0
         *
         * @return bool False if theme doesn't support the setting or user can't change setting, otherwise true.
         */
-       public final function check_capabilities() {
+       final public function check_capabilities() {
                if ( $this->capability && ! call_user_func_array( 'current_user_can', (array) $this->capability ) )
                        return false;
 
@@ -276,7 +710,7 @@ class WP_Customize_Setting {
         * @param $root
         * @param $keys
         * @param bool $create Default is false.
-        * @return null|array
+        * @return array|void Keys are 'root', 'node', and 'key'.
         */
        final protected function multidimensional( &$root, $keys, $create = false ) {
                if ( $create && empty( $root ) )
@@ -298,8 +732,15 @@ class WP_Customize_Setting {
                        $node = &$node[ $key ];
                }
 
-               if ( $create && ! isset( $node[ $last ] ) )
-                       $node[ $last ] = array();
+               if ( $create ) {
+                       if ( ! is_array( $node ) ) {
+                               // account for an array overriding a string or object value
+                               $node = array();
+                       }
+                       if ( ! isset( $node[ $last ] ) ) {
+                               $node[ $last ] = array();
+                       }
+               }
 
                if ( ! isset( $node[ $last ] ) )
                        return;
@@ -319,7 +760,7 @@ class WP_Customize_Setting {
         * @param $root
         * @param $keys
         * @param mixed $value The value to update.
-        * @return
+        * @return mixed
         */
        final protected function multidimensional_replace( $root, $keys, $value ) {
                if ( ! isset( $value ) )
@@ -342,7 +783,7 @@ class WP_Customize_Setting {
         *
         * @param $root
         * @param $keys
-        * @param $default A default value which is used as a fallback. Default is null.
+        * @param mixed $default A default value which is used as a fallback. Default is null.
         * @return mixed The requested value or the default value.
         */
        final protected function multidimensional_get( $root, $keys, $default = null ) {
@@ -368,42 +809,17 @@ class WP_Customize_Setting {
        }
 }
 
-/**
- * A setting that is used to filter a value, but will not save the results.
- *
- * Results should be properly handled using another setting or callback.
- */
-class WP_Customize_Filter_Setting extends WP_Customize_Setting {
-       public function update() {}
-}
-
-/**
- * A setting that is used to filter a value, but will not save the results.
- *
- * Results should be properly handled using another setting or callback.
- */
-final class WP_Customize_Header_Image_Setting extends WP_Customize_Setting {
-       public $id = 'header_image_data';
+/** WP_Customize_Filter_Setting class */
+require_once( ABSPATH . WPINC . '/customize/class-wp-customize-filter-setting.php' );
 
-       public function update( $value ) {
-               global $custom_image_header;
+/** WP_Customize_Header_Image_Setting class */
+require_once( ABSPATH . WPINC . '/customize/class-wp-customize-header-image-setting.php' );
 
-               // If the value doesn't exist (removed or random),
-               // use the header_image value.
-               if ( ! $value )
-                       $value = $this->manager->get_setting('header_image')->post_value();
+/** WP_Customize_Background_Image_Setting class */
+require_once( ABSPATH . WPINC . '/customize/class-wp-customize-background-image-setting.php' );
 
-               if ( is_array( $value ) && isset( $value['choice'] ) )
-                       $custom_image_header->set_header_image( $value['choice'] );
-               else
-                       $custom_image_header->set_header_image( $value );
-       }
-}
-
-final class WP_Customize_Background_Image_Setting extends WP_Customize_Setting {
-       public $id = 'background_image_thumb';
+/** WP_Customize_Nav_Menu_Item_Setting class */
+require_once( ABSPATH . WPINC . '/customize/class-wp-customize-nav-menu-item-setting.php' );
 
-       public function update( $value ) {
-               remove_theme_mod( 'background_image_thumb' );
-       }
-}
+/** WP_Customize_Nav_Menu_Setting class */
+require_once( ABSPATH . WPINC . '/customize/class-wp-customize-nav-menu-setting.php' );