Ticket #21883: class-wp-plugin.patch

wp-includes/class-wp-plugin.php

@@ +1 @@
+<?php
+
+/**
+ * The plugin API is located in this file, which allows for creating actions
+ * and filters and hooking functions, and methods. The functions or methods will
+ * then be run when the action or filter is called.
+ *
+ * The API callback examples reference functions, but can be methods of classes.
+ * To hook methods, you'll need to pass an array one of two ways.
+ *
+ * Any of the syntaxes explained in the PHP documentation for the
+ * {@link http://us2.php.net/manual/en/language.pseudo-types.php#language.types.callback 'callback'}
+ * type are valid.
+ *
+ * Also see the {@link http://codex.wordpress.org/Plugin_API Plugin API} for
+ * more information and examples on how to use a lot of these functions.
+ *
+ * @package WordPress
+ * @subpackage Plugin
+ * @since 1.5
+ */
+class WP_Plugin {
+
+        /**
+         * Array of actions and filters for this plugin
+         *
+         * @since 3.6
+         * @var array
+         */
+        public $_filters = array();
+
+        /**
+         * Array of actions and filters for this plugin
+         *
+         * @since 3.6
+         * @var array
+         */
+        public $_merged_filters = array();
+
+        /**
+         * The current filter(s) being run
+         *
+         * @since 3.6
+         * @var array
+         */
+        public $_current_filter = array();
+
+        /**
+         * A count of the number of times an action has fired
+         *
+         * @since 3.6
+         * @var array
+         */
+        public $_action_calls = array();
+
+        /** Filters ***************************************************************/
+
+        /**
+         * Hooks a function or method to a specific filter action.
+         *
+         * Filters are the hooks that WordPress launches to modify text of various types
+         * before adding it to the database or sending it to the browser screen. Plugins
+         * can specify that one or more of its PHP functions is executed to
+         * modify specific types of text at these times, using the Filter API.
+         *
+         * To use the API, the following code should be used to bind a callback to the
+         * filter.
+         *
+         * <code>
+         * function example_hook($example) { echo $example; }
+         * $plugin->add_filter('example_filter', 'example_hook');
+         * </code>
+         *
+         * In WordPress 1.5.1+, hooked functions can take extra arguments that are set
+         * when the matching do_action() or apply_filters() call is run. The
+         * $accepted_args allow for calling functions only when the number of args
+         * match. Hooked functions can take extra arguments that are set when the
+         * matching do_action() or apply_filters() call is run. For example, the action
+         * comment_id_not_found will pass any functions that hook onto it the ID of the
+         * requested comment.
+         *
+         * <strong>Note:</strong> the function will return true no matter if the
+         * function was hooked fails or not. There are no checks for whether the
+         * function exists beforehand and no checks to whether the <tt>$function_to_add
+         * is even a string. It is up to you to take care and this is done for
+         * optimization purposes, so everything is as quick as possible.
+         *
+         * @package WordPress
+         * @subpackage Plugin
+         * @since 0.71
+         *
+         * @param string $tag The name of the filter to hook the $function_to_add to.
+         * @param callback $function_to_add The name of the function to be called when the filter is applied.
+         * @param int $priority optional. Used to specify the order in which the functions associated with a particular action are executed (default: 10). Lower numbers correspond with earlier execution, and functions with the same priority are executed in the order in which they were added to the action.
+         * @param int $accepted_args optional. The number of arguments the function accept (default 1).
+         * @return boolean true
+         */
+        public function add_filter( $tag, $function_to_add, $priority = 10, $accepted_args = 1 ) {
+                $idx = $this->build_unique_id( $tag, $function_to_add, $priority );
+
+                $this->_filters[$tag][$priority][$idx] = array( 'function' => $function_to_add, 'accepted_args' => $accepted_args );
+
+                unset( $this->_merged_filters[$tag] );
+
+                return true;
+        }
+
+        /**
+         * Check if any filter has been registered for a hook.
+         *
+         * @package WordPress
+         * @subpackage Plugin
+         * @since 2.5
+         * @global array $this->_filters Stores all of the filters
+         *
+         * @param string $tag The name of the filter hook.
+         * @param callback $function_to_check optional.
+         * @return mixed If $function_to_check is omitted, returns boolean for whether the hook has anything registered.
+         *      When checking a specific function, the priority of that hook is returned, or false if the function is not attached.
+         *      When using the $function_to_check argument, this function may return a non-boolean value that evaluates to false
+         *      (e.g.) 0, so use the === operator for testing the return value.
+         */
+        public function has_filter( $tag, $function_to_check = false ) {
+
+                $has = !empty( $this->_filters[$tag] );
+                if ( false === $function_to_check || false == $has )
+                        return $has;
+
+                $idx = $this->build_unique_id( $tag, $function_to_check, false );
+                if ( empty( $idx ) )
+                        return false;
+
+                foreach ( (array) array_keys( $this->_filters[$tag] ) as $priority ) {
+                        if ( isset( $this->_filters[$tag][$priority][$idx] ) ) {
+                                return $priority;
+                        }
+                }
+
+                return false;
+        }
+
+        /**
+         * Call the functions added to a filter hook.
+         *
+         * The callback functions attached to filter hook $tag are invoked by calling
+         * this function. This function can be used to create a new filter hook by
+         * simply calling this function with the name of the new hook specified using
+         * the $tag parameter.
+         *
+         * The function allows for additional arguments to be added and passed to hooks.
+         * <code>
+         * function example_hook($string, $arg1, $arg2)
+         * {
+         *              //Do stuff
+         *              return $string;
+         * }
+         * $value = apply_filters('example_filter', 'filter me', 'arg1', 'arg2');
+         * </code>
+         *
+         * @package WordPress
+         * @subpackage Plugin
+         * @since 0.71
+         *
+         * @param string $tag The name of the filter hook.
+         * @param mixed $value The value on which the filters hooked to <tt>$tag</tt> are applied on.
+         * @param mixed $var,... Additional variables passed to the functions hooked to <tt>$tag</tt>.
+         * @return mixed The filtered value after all hooked functions are applied to it.
+         */
+        public function apply_filters( $tag, $value ) {
+
+                $args = array();
+
+                // Do 'all' actions first
+                if ( isset( $this->_filters['all'] ) ) {
+                        $this->_current_filter[] = $tag;
+                        $args                   = func_get_args();
+                        $this->call_all( $args );
+                }
+
+                if ( !isset( $this->_filters[$tag] ) ) {
+                        if ( isset( $this->_filters['all'] ) ) {
+                                array_pop( $this->_current_filter );
+                        }
+
+                        return $value;
+                }
+
+                if ( !isset( $this->_filters['all'] ) )
+                        $this->_current_filter[] = $tag;
+
+                // Sort
+                if ( !isset( $this->_merged_filters[$tag] ) ) {
+                        ksort( $this->_filters[$tag] );
+                        $this->_merged_filters[$tag] = true;
+                }
+
+                reset( $this->_filters[$tag] );
+
+                if ( empty( $args ) )
+                        $args = func_get_args();
+
+                do {
+                        foreach ( (array) current( $this->_filters[$tag] ) as $the_ ) {
+                                if ( !is_null( $the_['function'] ) ) {
+                                        $args[1] = $value;
+                                        $value   = call_user_func_array( $the_['function'], array_slice( $args, 1, (int) $the_['accepted_args'] ) );
+                                }
+                        }
+                } while ( next( $this->_filters[$tag] ) !== false );
+
+                array_pop( $this->_current_filter );
+
+                return $value;
+        }
+
+        /**
+         * Execute functions hooked on a specific filter hook, specifying arguments in an array.
+         *
+         * @see apply_filters() This function is identical, but the arguments passed to the
+         * functions hooked to <tt>$tag</tt> are supplied using an array.
+         *
+         * @package WordPress
+         * @subpackage Plugin
+         * @since 3.0.0
+         *
+         * @param string $tag The name of the filter hook.
+         * @param array $args The arguments supplied to the functions hooked to <tt>$tag</tt>
+         * @return mixed The filtered value after all hooked functions are applied to it.
+         */
+        public function apply_filters_ref_array( $tag, $args ) {
+
+                // Do 'all' actions first
+                if ( isset( $this->_filters['all'] ) ) {
+                        $this->_current_filter[] = $tag;
+                        $all_args               = func_get_args();
+                        $this->call_all( $all_args );
+                }
+
+                if ( !isset( $this->_filters[$tag] ) ) {
+                        if ( isset( $this->_filters['all'] ) ) {
+                                array_pop( $this->_current_filter );
+                        }
+
+                        return $args[0];
+                }
+
+                if ( !isset( $this->_filters['all'] ) ) {
+                        $this->_current_filter[] = $tag;
+                }
+
+                // Sort
+                if ( !isset( $this->_merged_filters[$tag] ) ) {
+                        ksort( $this->_filters[$tag] );
+                        $this->_merged_filters[$tag] = true;
+                }
+
+                reset( $this->_filters[$tag] );
+
+                do {
+                        foreach ( (array) current( $this->_filters[$tag] ) as $the_ ) {
+                                if ( !is_null( $the_['function'] ) ) {
+                                        $args[0] = call_user_func_array( $the_['function'], array_slice( $args, 0, (int) $the_['accepted_args'] ) );
+                                }
+                        }
+                } while ( next( $this->_filters[$tag] ) !== false );
+
+                array_pop( $this->_current_filter );
+
+                return $args[0];
+        }
+
+        /**
+         * Removes a function from a specified filter hook.
+         *
+         * This function removes a function attached to a specified filter hook. This
+         * method can be used to remove default functions attached to a specific filter
+         * hook and possibly replace them with a substitute.
+         *
+         * To remove a hook, the $function_to_remove and $priority arguments must match
+         * when the hook was added. This goes for both filters and actions. No warning
+         * will be given on removal failure.
+         *
+         * @package WordPress
+         * @subpackage Plugin
+         * @since 1.2
+         *
+         * @param string $tag The filter hook to which the function to be removed is hooked.
+         * @param callback $function_to_remove The name of the function which should be removed.
+         * @param int $priority optional. The priority of the function (default: 10).
+         * @param int $accepted_args optional. The number of arguments the function accepts (default: 1).
+         * @return boolean Whether the function existed before it was removed.
+         */
+        public function remove_filter( $tag, $function_to_remove, $priority = 10 ) {
+                $function_to_remove = $this->build_unique_id( $tag, $function_to_remove, $priority );
+
+                $r = isset( $this->_filters[$tag][$priority][$function_to_remove] );
+
+                if ( true === $r ) {
+                        unset( $this->_filters[$tag][$priority][$function_to_remove] );
+
+                        if ( empty( $this->_filters[$tag][$priority] ) ) {
+                                unset( $this->_filters[$tag][$priority] );
+                        }
+
+                        unset( $this->_merged_filters[$tag] );
+                }
+
+                return $r;
+        }
+
+        /**
+         * Remove all of the hooks from a filter.
+         *
+         * @since 2.7
+         *
+         * @param string $tag The filter to remove hooks from.
+         * @param int $priority The priority number to remove.
+         * @return bool True when finished.
+         */
+        public function remove_all_filters( $tag, $priority = false ) {
+
+                if ( isset( $this->_filters[$tag] ) ) {
+                        if ( false !== $priority && isset( $this->_filters[$tag][$priority] ) ) {
+                                unset( $this->_filters[$tag][$priority] );
+                        } else {
+                                unset( $this->_filters[$tag] );
+                        }
+                }
+
+                if ( isset( $this->_merged_filters[$tag] ) ) {
+                        unset( $this->_merged_filters[$tag] );
+                }
+
+                return true;
+        }
+
+        /**
+         * Retrieve the name of the current filter or action.
+         *
+         * @package WordPress
+         * @subpackage Plugin
+         * @since 2.5
+         *
+         * @return string Hook name of the current filter or action.
+         */
+        public function current_filter() {
+                return end( $this->_current_filter );
+        }
+
+        /**
+         * Hooks a function on to a specific action.
+         *
+         * Actions are the hooks that the WordPress core launches at specific points
+         * during execution, or when specific events occur. Plugins can specify that
+         * one or more of its PHP functions are executed at these points, using the
+         * Action API.
+         *
+         * @uses WP_Plugin::add_filter() Adds an action. Parameter list and functionality are the same.
+         *
+         * @package WordPress
+         * @subpackage Plugin
+         * @since 1.2
+         *
+         * @param string $tag The name of the action to which the $function_to_add is hooked.
+         * @param callback $function_to_add The name of the function you wish to be called.
+         * @param int $priority optional. Used to specify the order in which the functions associated with a particular action are executed (default: 10). Lower numbers correspond with earlier execution, and functions with the same priority are executed in the order in which they were added to the action.
+         * @param int $accepted_args optional. The number of arguments the function accept (default 1).
+         */
+        public function add_action( $tag, $function_to_add, $priority = 10, $accepted_args = 1 ) {
+                return $this->add_filter( $tag, $function_to_add, $priority, $accepted_args );
+        }
+
+        /**
+         * Execute functions hooked on a specific action hook.
+         *
+         * This function invokes all functions attached to action hook $tag. It is
+         * possible to create new action hooks by simply calling this function,
+         * specifying the name of the new hook using the <tt>$tag</tt> parameter.
+         *
+         * You can pass extra arguments to the hooks, much like you can with
+         * apply_filters().
+         *
+         * @see apply_filters() This function works similar with the exception that
+         * nothing is returned and only the functions or methods are called.
+         *
+         * @package WordPress
+         * @subpackage Plugin
+         * @since 1.2
+         *
+         * @param string $tag The name of the action to be executed.
+         * @param mixed $arg,... Optional additional arguments which are passed on to the functions hooked to the action.
+         * @return null Will return null if $tag does not exist in $this->_filters array
+         */
+        public function do_action( $tag, $arg = '' ) {
+
+                if ( !isset( $this->_action_calls ) )
+                        $this->_action_calls = array();
+
+                if ( !isset( $this->_action_calls[$tag] ) )
+                        $this->_action_calls[$tag] = 1;
+                else
+                        ++$this->_action_calls[$tag];
+
+                // Do 'all' actions first
+                if ( isset( $this->_filters['all'] ) ) {
+                        $this->_current_filter[] = $tag;
+                        $all_args               = func_get_args();
+                        $this->call_all( $all_args );
+                }
+
+                if ( !isset( $this->_filters[$tag] ) ) {
+                        if ( isset( $this->_filters['all'] ) ) {
+                                array_pop( $this->_current_filter );
+                        }
+
+                        return;
+                }
+
+                if ( !isset( $this->_filters['all'] ) )
+                        $this->_current_filter[] = $tag;
+
+                $args = array();
+                
+                if ( is_array( $arg ) && 1 == count( $arg ) && isset( $arg[0] ) && is_object( $arg[0] ) )
+                        $args[]  = & $arg[0];
+                else
+                        $args[]  = $arg;
+
+                for ( $a = 2; $a < func_num_args(); $a++ )
+                        $args[]  = func_get_arg( $a );
+
+                // Sort
+                if ( !isset( $this->_merged_filters[$tag] ) ) {
+                        ksort( $this->_filters[$tag] );
+                        $this->_merged_filters[$tag] = true;
+                }
+
+                reset( $this->_filters[$tag] );
+
+                do {
+                        foreach ( (array) current( $this->_filters[$tag] ) as $the_ ) {
+                                if ( !is_null( $the_['function'] ) ) {
+                                        call_user_func_array( $the_['function'], array_slice( $args, 0, (int) $the_['accepted_args'] ) );
+                                }
+                        }
+                } while ( next( $this->_filters[$tag] ) !== false );
+
+                array_pop( $this->_current_filter );
+        }
+
+        /**
+         * Retrieve the number of times an action is fired.
+         *
+         * @package WordPress
+         * @subpackage Plugin
+         * @since 2.1
+         * @global array $this->_action_calls Increments the amount of times action was triggered.
+         *
+         * @param string $tag The name of the action hook.
+         * @return int The number of times action hook <tt>$tag</tt> is fired
+         */
+        public function did_action( $tag ) {
+
+                if ( !isset( $this->_action_calls ) || !isset( $this->_action_calls[$tag] ) )
+                        return 0;
+
+                return $this->_action_calls[$tag];
+        }
+
+        /**
+         * Execute functions hooked on a specific action hook, specifying arguments in an array.
+         *
+         * @see do_action() This function is identical, but the arguments passed to the
+         * functions hooked to <tt>$tag</tt> are supplied using an array.
+         *
+         * @package WordPress
+         * @subpackage Plugin
+         * @since 2.1
+         * @global array $this->_filters Stores all of the filters
+         * @global array $this->_action_calls Increments the amount of times action was triggered.
+         *
+         * @param string $tag The name of the action to be executed.
+         * @param array $args The arguments supplied to the functions hooked to <tt>$tag</tt>
+         * @return null Will return null if $tag does not exist in $this->_filters array
+         */
+        public function do_action_ref_array( $tag, $args ) {
+
+                if ( !isset( $this->_action_calls ) )
+                        $this->_action_calls = array( );
+
+                if ( !isset( $this->_action_calls[$tag] ) )
+                        $this->_action_calls[$tag] = 1;
+                else
+                        ++$this->_action_calls[$tag];
+
+                // Do 'all' actions first
+                if ( isset( $this->_filters['all'] ) ) {
+                        $this->_current_filter[] = $tag;
+                        $all_args               = func_get_args();
+                        $this->call_all( $all_args );
+                }
+
+                if ( !isset( $this->_filters[$tag] ) ) {
+                        if ( isset( $this->_filters['all'] ) ) {
+                                array_pop( $this->_current_filter );
+                        }
+                        return;
+                }
+
+                if ( !isset( $this->_filters['all'] ) )
+                        $this->_current_filter[] = $tag;
+
+                // Sort
+                if ( !isset( $this->_merged_filters[$tag] ) ) {
+                        ksort( $this->_filters[$tag] );
+                        $this->_merged_filters[$tag] = true;
+                }
+
+                reset( $this->_filters[$tag] );
+
+                do {
+                        foreach ( (array) current( $this->_filters[$tag] ) as $the_ ) {
+                                if ( !is_null( $the_['function'] ) ) {
+                                        call_user_func_array( $the_['function'], array_slice( $args, 0, (int) $the_['accepted_args'] ) );
+                                }
+                        }
+                } while ( next( $this->_filters[$tag] ) !== false );
+
+                array_pop( $this->_current_filter );
+        }
+
+        /**
+         * Check if any action has been registered for a hook.
+         *
+         * @package WordPress
+         * @subpackage Plugin
+         * @since 2.5
+         * @see has_filter() has_action() is an alias of has_filter().
+         *
+         * @param string $tag The name of the action hook.
+         * @param callback $function_to_check optional.
+         * @return mixed If $function_to_check is omitted, returns boolean for whether the hook has anything registered.
+         *      When checking a specific function, the priority of that hook is returned, or false if the function is not attached.
+         *      When using the $function_to_check argument, this function may return a non-boolean value that evaluates to false
+         *      (e.g.) 0, so use the === operator for testing the return value.
+         */
+        public function has_action( $tag, $function_to_check = false ) {
+                return $this->has_filter( $tag, $function_to_check );
+        }
+
+        /**
+         * Removes a function from a specified action hook.
+         *
+         * This function removes a function attached to a specified action hook. This
+         * method can be used to remove default functions attached to a specific filter
+         * hook and possibly replace them with a substitute.
+         *
+         * @package WordPress
+         * @subpackage Plugin
+         * @since 1.2
+         *
+         * @param string $tag The action hook to which the function to be removed is hooked.
+         * @param callback $function_to_remove The name of the function which should be removed.
+         * @param int $priority optional The priority of the function (default: 10).
+         * @return boolean Whether the function is removed.
+         */
+        public function remove_action( $tag, $function_to_remove, $priority = 10 ) {
+                return $this->remove_filter( $tag, $function_to_remove, $priority );
+        }
+
+        /**
+         * Remove all of the hooks from an action.
+         *
+         * @since 2.7
+         *
+         * @param string $tag The action to remove hooks from.
+         * @param int $priority The priority number to remove them from.
+         * @return bool True when finished.
+         */
+        public function remove_all_actions( $tag, $priority = false ) {
+                return $this->remove_all_filters( $tag, $priority );
+        }
+
+        /**
+         * Set the activation hook for a plugin.
+         *
+         * When a plugin is activated, the action 'activate_PLUGINNAME' hook is
+         * activated. In the name of this hook, PLUGINNAME is replaced with the name of
+         * the plugin, including the optional subdirectory. For example, when the plugin
+         * is located in wp-content/plugin/sampleplugin/sample.php, then the name of
+         * this hook will become 'activate_sampleplugin/sample.php'. When the plugin
+         * consists of only one file and is (as by default) located at
+         * wp-content/plugin/sample.php the name of this hook will be
+         * 'activate_sample.php'.
+         *
+         * @package WordPress
+         * @subpackage Plugin
+         * @since 2.0
+         *
+         * @param string $file The filename of the plugin including the path.
+         * @param callback $function the function hooked to the 'activate_PLUGIN' action.
+         */
+        public function register_activation_hook( $file, $function ) {
+                $file = plugin_basename( $file );
+                $this->add_action( 'activate_' . $file, $function );
+        }
+
+        /**
+         * Set the deactivation hook for a plugin.
+         *
+         * When a plugin is deactivated, the action 'deactivate_PLUGINNAME' hook is
+         * deactivated. In the name of this hook, PLUGINNAME is replaced with the name
+         * of the plugin, including the optional subdirectory. For example, when the
+         * plugin is located in wp-content/plugin/sampleplugin/sample.php, then
+         * the name of this hook will become 'activate_sampleplugin/sample.php'.
+         *
+         * When the plugin consists of only one file and is (as by default) located at
+         * wp-content/plugin/sample.php the name of this hook will be
+         * 'activate_sample.php'.
+         *
+         * @package WordPress
+         * @subpackage Plugin
+         * @since 2.0
+         *
+         * @param string $file The filename of the plugin including the path.
+         * @param callback $function the function hooked to the 'activate_PLUGIN' action.
+         */
+        public function register_deactivation_hook( $file, $function ) {
+                $file = plugin_basename( $file );
+                $this->add_action( 'deactivate_' . $file, $function );
+        }
+
+        /**
+         * Set the uninstallation hook for a plugin.
+         *
+         * Registers the uninstall hook that will be called when the user clicks on the
+         * uninstall link that calls for the plugin to uninstall itself. The link won't
+         * be active unless the plugin hooks into the action.
+         *
+         * The plugin should not run arbitrary code outside of functions, when
+         * registering the uninstall hook. In order to run using the hook, the plugin
+         * will have to be included, which means that any code laying outside of a
+         * function will be run during the uninstall process. The plugin should not
+         * hinder the uninstall process.
+         *
+         * If the plugin can not be written without running code within the plugin, then
+         * the plugin should create a file named 'uninstall.php' in the base plugin
+         * folder. This file will be called, if it exists, during the uninstall process
+         * bypassing the uninstall hook. The plugin, when using the 'uninstall.php'
+         * should always check for the 'WP_UNINSTALL_PLUGIN' constant, before
+         * executing.
+         *
+         * @since 2.7
+         *
+         * @param string $file
+         * @param callback $callback The callback to run when the hook is called. Must be a static method or function.
+         */
+        public function register_uninstall_hook( $file, $callback ) {
+                if ( is_array( $callback ) && is_object( $callback[0] ) ) {
+                        _doing_it_wrong( __FUNCTION__, __( 'Only a static class method or function can be used in an uninstall hook.' ), '3.1' );
+                        return;
+                }
+
+                // The option should not be autoloaded, because it is not needed in most
+                // cases. Emphasis should be put on using the 'uninstall.php' way of
+                // uninstalling the plugin.
+                $file                         = plugin_basename( $file );
+                $uninstallable_plugins        = (array) get_option( 'uninstall_plugins' );
+                $uninstallable_plugins[$file] = $callback;
+                update_option( 'uninstall_plugins', $uninstallable_plugins );
+        }
+
+        /**
+         * Calls the 'all' hook, which will process the functions hooked into it.
+         *
+         * The 'all' hook passes all of the arguments or parameters that were used for
+         * the hook, which this function was called for.
+         *
+         * This function is used internally for apply_filters(), do_action(), and
+         * do_action_ref_array() and is not meant to be used from outside those
+         * functions. This function does not check for the existence of the all hook, so
+         * it will fail unless the all hook exists prior to this function call.
+         *
+         * @package WordPress
+         * @subpackage Plugin
+         * @since 2.5
+         * @access private
+         *
+         * @uses $this->_filters Used to process all of the functions in the 'all' hook
+         *
+         * @param array $args The collected parameters from the hook that was called.
+         * @param string $hook Optional. The hook name that was used to call the 'all' hook.
+         */
+        private function call_all( $args ) {
+                reset( $this->_filters['all'] );
+                do {
+                        foreach ( (array) current( $this->_filters['all'] ) as $the_ ) {
+                                if ( !is_null( $the_['function'] ) ) {
+                                        call_user_func_array( $the_['function'], $args );
+                                }
+                        }
+                } while ( next( $this->_filters['all'] ) !== false );
+        }
+
+        /**
+         * Build Unique ID for storage and retrieval.
+         *
+         * The old way to serialize the callback caused issues and this function is the
+         * solution. It works by checking for objects and creating an a new property in
+         * the class to keep track of the object and new objects of the same class that
+         * need to be added.
+         *
+         * It also allows for the removal of actions and filters for objects after they
+         * change class properties. It is possible to include the property $this->_filters_id
+         * in your class and set it to "null" or a number to bypass the workaround.
+         * However this will prevent you from adding new classes and any new classes
+         * will overwrite the previous hook by the same class.
+         *
+         * Functions and static method callbacks are just returned as strings and
+         * shouldn't have any speed penalty.
+         *
+         * @package WordPress
+         * @subpackage Plugin
+         * @access private
+         * @since 2.2.3
+         * @link http://trac.wordpress.org/ticket/3875
+         *
+         * @global array $this->_filters Storage for all of the filters and actions
+         * @param string $tag Used in counting how many hooks were applied
+         * @param callback $function Used for creating unique id
+         * @param int|bool $priority Used in counting how many hooks were applied. If === false and $function is an object reference, we return the unique id only if it already has one, false otherwise.
+         * @return string|bool Unique ID for usage as array key or false if $priority === false and $function is an object reference, and it does not already have a unique id.
+         */
+        private function build_unique_id( $tag, $function, $priority ) {
+                static $filter_id_count = 0;
+
+                if ( is_string( $function ) )
+                        return $function;
+
+                // Closures are currently implemented as objects
+                if ( is_object( $function ) ) {
+                        $function = array( $function, '' );
+                } else {
+                        $function = (array) $function;
+                }
+
+                // Object Class Calling
+                if ( is_object( $function[0] ) ) {
+                        if ( function_exists( 'spl_object_hash' ) ) {
+                                return spl_object_hash( $function[0] ) . $function[1];
+                        } else {
+                                $obj_idx = get_class( $function[0] ) . $function[1];
+                                if ( !isset( $function[0]->wp_filter_id ) ) {
+                                        if ( false === $priority ) {
+                                                return false;
+                                        }
+
+                                        if ( isset( $this->_filters[$tag][$priority] ) ) {
+                                                $obj_idx = count( (array) $this->_filters[$tag][$priority] );
+                                        } else {
+                                                $obj_idx = $filter_id_count;
+                                        }
+
+                                        $function[0]->wp_filter_id = $filter_id_count;
+
+                                        ++$filter_id_count;
+                                } else {
+                                        $obj_idx .= $function[0]->wp_filter_id;
+                                }
+
+                                return $obj_idx;
+                        }
+
+                // Static Calling
+                } elseif ( is_string( $function[0] ) ) {
+                        return $function[0] . $function[1];
+                }
+        }
+}

wp-includes/plugin.php

@@ -19 +19 @@
  * @since 1.5
  */
 
+function wp_global_hooks() {
+
+        if ( ! isset( $GLOBALS['wp_global_hooks'] ) ) {
+                $GLOBALS['wp_global_hooks']   = new WP_Plugin();
+                $GLOBALS['wp_actions']        = &$GLOBALS['wp_global_hooks']->_action_calls;
+                $GLOBALS['wp_filter']         = &$GLOBALS['wp_global_hooks']->_filters;
+                $GLOBALS['merged_filters']    = &$GLOBALS['wp_global_hooks']->_merged_filters;
+                $GLOBALS['wp_current_filter'] = &$GLOBALS['wp_global_hooks']->_current_filter;
+        }
+
+        return $GLOBALS['wp_global_hooks'];
+}
+
 /**
  * Hooks a function or method to a specific filter action.
  *
@@ -52 +65 @@
  * @package WordPress
  * @subpackage Plugin
  * @since 0.71
- * @global array $wp_filter Stores all of the filters added in the form of
- *      wp_filter['tag']['array of priorities']['array of functions serialized']['array of ['array (functions, accepted_args)']']
- * @global array $merged_filters Tracks the tags that need to be merged for later. If the hook is added, it doesn't need to run through that process.
  *
  * @param string $tag The name of the filter to hook the $function_to_add to.
  * @param callback $function_to_add The name of the function to be called when the filter is applied.
@@ -62 +72 @@
  * @param int $accepted_args optional. The number of arguments the function accept (default 1).
  * @return boolean true
  */
-function add_filter($tag, $function_to_add, $priority = 10, $accepted_args = 1) {
-        global $wp_filter, $merged_filters;
-
-        $idx = _wp_filter_build_unique_id($tag, $function_to_add, $priority);
-        $wp_filter[$tag][$priority][$idx] = array('function' => $function_to_add, 'accepted_args' => $accepted_args);
-        unset( $merged_filters[ $tag ] );
-        return true;
+function add_filter( $tag, $function_to_add, $priority = 10, $accepted_args = 1 ) {
+        return wp_global_hooks()->add_filter( $tag, $function_to_add, $priority, $accepted_args );
 }
 
 /**
@@ -77 +82 @@
  * @package WordPress
  * @subpackage Plugin
  * @since 2.5
- * @global array $wp_filter Stores all of the filters
  *
  * @param string $tag The name of the filter hook.
  * @param callback $function_to_check optional.
@@ -86 +90 @@
  *      When using the $function_to_check argument, this function may return a non-boolean value that evaluates to false
  *      (e.g.) 0, so use the === operator for testing the return value.
  */
-function has_filter($tag, $function_to_check = false) {
-        global $wp_filter;
-
-        $has = !empty($wp_filter[$tag]);
-        if ( false === $function_to_check || false == $has )
-                return $has;
-
-        if ( !$idx = _wp_filter_build_unique_id($tag, $function_to_check, false) )
-                return false;
-
-        foreach ( (array) array_keys($wp_filter[$tag]) as $priority ) {
-                if ( isset($wp_filter[$tag][$priority][$idx]) )
-                        return $priority;
-        }
-
-        return false;
+function has_filter( $tag, $function_to_check = false ) {
+        return wp_global_hooks()->has_filter( $tag, $function_to_check );
 }
 
 /**
@@ -125 +115 @@
  * @package WordPress
  * @subpackage Plugin
  * @since 0.71
- * @global array $wp_filter Stores all of the filters
- * @global array $merged_filters Merges the filter hooks using this function.
- * @global array $wp_current_filter stores the list of current filters with the current one last
  *
  * @param string $tag The name of the filter hook.
  * @param mixed $value The value on which the filters hooked to <tt>$tag</tt> are applied on.
  * @param mixed $var,... Additional variables passed to the functions hooked to <tt>$tag</tt>.
  * @return mixed The filtered value after all hooked functions are applied to it.
  */
-function apply_filters($tag, $value) {
-        global $wp_filter, $merged_filters, $wp_current_filter;
+function apply_filters( $tag, $value ) {
 
         $args = array();
 
         // Do 'all' actions first
-        if ( isset($wp_filter['all']) ) {
-                $wp_current_filter[] = $tag;
-                $args = func_get_args();
-                _wp_call_all_hook($args);
+        if ( isset( wp_global_hooks()->_filters['all'] ) ) {
+                wp_global_hooks()->_current_filter[] = $tag;
+                $args                   = func_get_args();
+                wp_global_hooks()->call_all( $args );
         }
 
-        if ( !isset($wp_filter[$tag]) ) {
-                if ( isset($wp_filter['all']) )
-                        array_pop($wp_current_filter);
+        if ( !isset( wp_global_hooks()->_filters[$tag] ) ) {
+                if ( isset( wp_global_hooks()->_filters['all'] ) ) {
+                        array_pop( wp_global_hooks()->_current_filter );
+                }
+
                 return $value;
         }
 
-        if ( !isset($wp_filter['all']) )
-                $wp_current_filter[] = $tag;
+        if ( !isset( wp_global_hooks()->_filters['all'] ) )
+                wp_global_hooks()->_current_filter[] = $tag;
 
         // Sort
-        if ( !isset( $merged_filters[ $tag ] ) ) {
-                ksort($wp_filter[$tag]);
-                $merged_filters[ $tag ] = true;
+        if ( !isset( wp_global_hooks()->_merged_filters[$tag] ) ) {
+                ksort( wp_global_hooks()->_filters[$tag] );
+                wp_global_hooks()->_merged_filters[$tag] = true;
         }
 
-        reset( $wp_filter[ $tag ] );
+        reset( wp_global_hooks()->_filters[$tag] );
 
-        if ( empty($args) )
+        if ( empty( $args ) )
                 $args = func_get_args();
 
         do {
-                foreach( (array) current($wp_filter[$tag]) as $the_ )
-                        if ( !is_null($the_['function']) ){
+                foreach ( (array) current( wp_global_hooks()->_filters[$tag] ) as $the_ ) {
+                        if ( !is_null( $the_['function'] ) ) {
                                 $args[1] = $value;
-                                $value = call_user_func_array($the_['function'], array_slice($args, 1, (int) $the_['accepted_args']));
+                                $value   = call_user_func_array( $the_['function'], array_slice( $args, 1, (int) $the_['accepted_args'] ) );
                         }
+                }
+        } while ( next( wp_global_hooks()->_filters[$tag] ) !== false );
 
-        } while ( next($wp_filter[$tag]) !== false );
+        array_pop( wp_global_hooks()->_current_filter );
 
-        array_pop( $wp_current_filter );
-
         return $value;
 }
 
@@ -189 +177 @@
  * @package WordPress
  * @subpackage Plugin
  * @since 3.0.0
- * @global array $wp_filter Stores all of the filters
- * @global array $merged_filters Merges the filter hooks using this function.
- * @global array $wp_current_filter stores the list of current filters with the current one last
  *
  * @param string $tag The name of the filter hook.
  * @param array $args The arguments supplied to the functions hooked to <tt>$tag</tt>
  * @return mixed The filtered value after all hooked functions are applied to it.
  */
-function apply_filters_ref_array($tag, $args) {
-        global $wp_filter, $merged_filters, $wp_current_filter;
-
-        // Do 'all' actions first
-        if ( isset($wp_filter['all']) ) {
-                $wp_current_filter[] = $tag;
-                $all_args = func_get_args();
-                _wp_call_all_hook($all_args);
-        }
-
-        if ( !isset($wp_filter[$tag]) ) {
-                if ( isset($wp_filter['all']) )
-                        array_pop($wp_current_filter);
-                return $args[0];
-        }
-
-        if ( !isset($wp_filter['all']) )
-                $wp_current_filter[] = $tag;
-
-        // Sort
-        if ( !isset( $merged_filters[ $tag ] ) ) {
-                ksort($wp_filter[$tag]);
-                $merged_filters[ $tag ] = true;
-        }
-
-        reset( $wp_filter[ $tag ] );
-
-        do {
-                foreach( (array) current($wp_filter[$tag]) as $the_ )
-                        if ( !is_null($the_['function']) )
-                                $args[0] = call_user_func_array($the_['function'], array_slice($args, 0, (int) $the_['accepted_args']));
-
-        } while ( next($wp_filter[$tag]) !== false );
-
-        array_pop( $wp_current_filter );
-
-        return $args[0];
+function apply_filters_ref_array( $tag, $args ) {
+        return wp_global_hooks()->apply_filters_ref_array( $tag, $args );
 }
 
 /**
@@ -258 +208 @@
  * @return boolean Whether the function existed before it was removed.
  */
 function remove_filter( $tag, $function_to_remove, $priority = 10 ) {
-        $function_to_remove = _wp_filter_build_unique_id($tag, $function_to_remove, $priority);
-
-        $r = isset($GLOBALS['wp_filter'][$tag][$priority][$function_to_remove]);
-
-        if ( true === $r) {
-                unset($GLOBALS['wp_filter'][$tag][$priority][$function_to_remove]);
-                if ( empty($GLOBALS['wp_filter'][$tag][$priority]) )
-                        unset($GLOBALS['wp_filter'][$tag][$priority]);
-                unset($GLOBALS['merged_filters'][$tag]);
-        }
-
-        return $r;
+        return wp_global_hooks()->remove_filter( $tag, $function_to_remove, $priority );
 }
 
 /**
@@ -282 +221 @@
  * @return bool True when finished.
  */
 function remove_all_filters($tag, $priority = false) {
-        global $wp_filter, $merged_filters;
-
-        if( isset($wp_filter[$tag]) ) {
-                if( false !== $priority && isset($wp_filter[$tag][$priority]) )
-                        unset($wp_filter[$tag][$priority]);
-                else
-                        unset($wp_filter[$tag]);
-        }
-
-        if( isset($merged_filters[$tag]) )
-                unset($merged_filters[$tag]);
-
-        return true;
+        return wp_global_hooks()->remove_all_filters( $tag, $priority );
 }
 
 /**
@@ -307 +234 @@
  * @return string Hook name of the current filter or action.
  */
 function current_filter() {
-        global $wp_current_filter;
-        return end( $wp_current_filter );
+        return wp_global_hooks()->current_filter();
 }
 
 /**
@@ -331 +257 @@
  * @param int $accepted_args optional. The number of arguments the function accept (default 1).
  */
 function add_action($tag, $function_to_add, $priority = 10, $accepted_args = 1) {
-        return add_filter($tag, $function_to_add, $priority, $accepted_args);
+        return wp_global_hooks()->add_action($tag, $function_to_add, $priority, $accepted_args );
 }
 
 /**
@@ -350 +276 @@
  * @package WordPress
  * @subpackage Plugin
  * @since 1.2
- * @global array $wp_filter Stores all of the filters
- * @global array $wp_actions Increments the amount of times action was triggered.
  *
  * @param string $tag The name of the action to be executed.
  * @param mixed $arg,... Optional additional arguments which are passed on to the functions hooked to the action.
  * @return null Will return null if $tag does not exist in $wp_filter array
  */
 function do_action($tag, $arg = '') {
-        global $wp_filter, $wp_actions, $merged_filters, $wp_current_filter;
+        if ( !isset( wp_global_hooks()->_action_calls ) )
+                wp_global_hooks()->_action_calls = array();
 
-        if ( ! isset($wp_actions) )
-                $wp_actions = array();
-
-        if ( ! isset($wp_actions[$tag]) )
-                $wp_actions[$tag] = 1;
+        if ( !isset( wp_global_hooks()->_action_calls[$tag] ) )
+                wp_global_hooks()->_action_calls[$tag] = 1;
         else
-                ++$wp_actions[$tag];
+                ++wp_global_hooks()->_action_calls[$tag];
 
         // Do 'all' actions first
-        if ( isset($wp_filter['all']) ) {
-                $wp_current_filter[] = $tag;
-                $all_args = func_get_args();
-                _wp_call_all_hook($all_args);
+        if ( isset( wp_global_hooks()->_filters['all'] ) ) {
+                wp_global_hooks()->_current_filter[] = $tag;
+                $all_args               = func_get_args();
+                wp_global_hooks()->call_all( $all_args );
         }
 
-        if ( !isset($wp_filter[$tag]) ) {
-                if ( isset($wp_filter['all']) )
-                        array_pop($wp_current_filter);
+        if ( !isset( wp_global_hooks()->_filters[$tag] ) ) {
+                if ( isset( wp_global_hooks()->_filters['all'] ) ) {
+                        array_pop( wp_global_hooks()->_current_filter );
+                }
+
                 return;
         }
 
-        if ( !isset($wp_filter['all']) )
-                $wp_current_filter[] = $tag;
+        if ( !isset( wp_global_hooks()->_filters['all'] ) )
+                wp_global_hooks()->_current_filter[] = $tag;
 
         $args = array();
-        if ( is_array($arg) && 1 == count($arg) && isset($arg[0]) && is_object($arg[0]) ) // array(&$this)
-                $args[] =& $arg[0];
+
+        if ( is_array( $arg ) && 1 == count( $arg ) && isset( $arg[0] ) && is_object( $arg[0] ) )
+                $args[]  = & $arg[0];
         else
-                $args[] = $arg;
+                $args[]  = $arg;
+
         for ( $a = 2; $a < func_num_args(); $a++ )
-                $args[] = func_get_arg($a);
+                $args[]  = func_get_arg( $a );
 
         // Sort
-        if ( !isset( $merged_filters[ $tag ] ) ) {
-                ksort($wp_filter[$tag]);
-                $merged_filters[ $tag ] = true;
+        if ( !isset( wp_global_hooks()->_merged_filters[$tag] ) ) {
+                ksort( wp_global_hooks()->_filters[$tag] );
+                wp_global_hooks()->_merged_filters[$tag] = true;
         }
 
-        reset( $wp_filter[ $tag ] );
+        reset( wp_global_hooks()->_filters[$tag] );
 
         do {
-                foreach ( (array) current($wp_filter[$tag]) as $the_ )
-                        if ( !is_null($the_['function']) )
-                                call_user_func_array($the_['function'], array_slice($args, 0, (int) $the_['accepted_args']));
+                foreach ( (array) current( wp_global_hooks()->_filters[$tag] ) as $the_ ) {
+                        if ( !is_null( $the_['function'] ) ) {
+                                call_user_func_array( $the_['function'], array_slice( $args, 0, (int) $the_['accepted_args'] ) );
+                        }
+                }
+        } while ( next( wp_global_hooks()->_filters[$tag] ) !== false );
 
-        } while ( next($wp_filter[$tag]) !== false );
-
-        array_pop($wp_current_filter);
+        array_pop( wp_global_hooks()->_current_filter );
 }
 
 /**
@@ -422 +349 @@
  * @return int The number of times action hook <tt>$tag</tt> is fired
  */
 function did_action($tag) {
-        global $wp_actions;
-
-        if ( ! isset( $wp_actions ) || ! isset( $wp_actions[$tag] ) )
-                return 0;
-
-        return $wp_actions[$tag];
+        return wp_global_hooks()->did_action( $tag );
 }
 
 /**
@@ -447 +369 @@
  * @return null Will return null if $tag does not exist in $wp_filter array
  */
 function do_action_ref_array($tag, $args) {
-        global $wp_filter, $wp_actions, $merged_filters, $wp_current_filter;
-
-        if ( ! isset($wp_actions) )
-                $wp_actions = array();
-
-        if ( ! isset($wp_actions[$tag]) )
-                $wp_actions[$tag] = 1;
-        else
-                ++$wp_actions[$tag];
-
-        // Do 'all' actions first
-        if ( isset($wp_filter['all']) ) {
-                $wp_current_filter[] = $tag;
-                $all_args = func_get_args();
-                _wp_call_all_hook($all_args);
-        }
-
-        if ( !isset($wp_filter[$tag]) ) {
-                if ( isset($wp_filter['all']) )
-                        array_pop($wp_current_filter);
-                return;
-        }
-
-        if ( !isset($wp_filter['all']) )
-                $wp_current_filter[] = $tag;
-
-        // Sort
-        if ( !isset( $merged_filters[ $tag ] ) ) {
-                ksort($wp_filter[$tag]);
-                $merged_filters[ $tag ] = true;
-        }
-
-        reset( $wp_filter[ $tag ] );
-
-        do {
-                foreach( (array) current($wp_filter[$tag]) as $the_ )
-                        if ( !is_null($the_['function']) )
-                                call_user_func_array($the_['function'], array_slice($args, 0, (int) $the_['accepted_args']));
-
-        } while ( next($wp_filter[$tag]) !== false );
-
-        array_pop($wp_current_filter);
+        wp_global_hooks()->do_action_ref_array( $tag, $args );
 }
 
 /**
@@ -507 +388 @@
  *      (e.g.) 0, so use the === operator for testing the return value.
  */
 function has_action($tag, $function_to_check = false) {
-        return has_filter($tag, $function_to_check);
+        return wp_global_hooks()->has_action( $tag, $function_to_check );
 }
 
 /**
@@ -527 +408 @@
  * @return boolean Whether the function is removed.
  */
 function remove_action( $tag, $function_to_remove, $priority = 10 ) {
-        return remove_filter( $tag, $function_to_remove, $priority );
+        return wp_global_hooks()->remove_filter( $tag, $function_to_remove, $priority );
 }
 
 /**
@@ -540 +421 @@
  * @return bool True when finished.
  */
 function remove_all_actions($tag, $priority = false) {
-        return remove_all_filters($tag, $priority);
+        return wp_global_hooks()->remove_all_filters( $tag, $priority );
 }
 
 //
@@ -710 +591 @@
  * @param string $hook Optional. The hook name that was used to call the 'all' hook.
  */
 function _wp_call_all_hook($args) {
-        global $wp_filter;
-
-        reset( $wp_filter['all'] );
-        do {
-                foreach( (array) current($wp_filter['all']) as $the_ )
-                        if ( !is_null($the_['function']) )
-                                call_user_func_array($the_['function'], $args);
-
-        } while ( next($wp_filter['all']) !== false );
+        return wp_global_hooks()->call_all( $args );
 }
 
 /**
@@ -751 +624 @@
  * @return string|bool Unique ID for usage as array key or false if $priority === false and $function is an object reference, and it does not already have a unique id.
  */
 function _wp_filter_build_unique_id($tag, $function, $priority) {
-        global $wp_filter;
-        static $filter_id_count = 0;
-
-        if ( is_string($function) )
-                return $function;
-
-        if ( is_object($function) ) {
-                // Closures are currently implemented as objects
-                $function = array( $function, '' );
-        } else {
-                $function = (array) $function;
-        }
-
-        if (is_object($function[0]) ) {
-                // Object Class Calling
-                if ( function_exists('spl_object_hash') ) {
-                        return spl_object_hash($function[0]) . $function[1];
-                } else {
-                        $obj_idx = get_class($function[0]).$function[1];
-                        if ( !isset($function[0]->wp_filter_id) ) {
-                                if ( false === $priority )
-                                        return false;
-                                $obj_idx .= isset($wp_filter[$tag][$priority]) ? count((array)$wp_filter[$tag][$priority]) : $filter_id_count;
-                                $function[0]->wp_filter_id = $filter_id_count;
-                                ++$filter_id_count;
-                        } else {
-                                $obj_idx .= $function[0]->wp_filter_id;
-                        }
-
-                        return $obj_idx;
-                }
-        } else if ( is_string($function[0]) ) {
-                // Static Calling
-                return $function[0].$function[1];
-        }
+        return wp_global_hooks()->build_unique_id( $tag, $function, $priority );
 }

wp-settings.php

@@ -61 +61 @@
 wp_set_lang_dir();
 
 // Load early WordPress files.
-require( ABSPATH . WPINC . '/compat.php' );
-require( ABSPATH . WPINC . '/functions.php' );
-require( ABSPATH . WPINC . '/class-wp.php' );
-require( ABSPATH . WPINC . '/class-wp-error.php' );
-require( ABSPATH . WPINC . '/plugin.php' );
-require( ABSPATH . WPINC . '/pomo/mo.php' );
+require( ABSPATH . WPINC . '/compat.php'          );
+require( ABSPATH . WPINC . '/functions.php'       );
+require( ABSPATH . WPINC . '/class-wp.php'        );
+require( ABSPATH . WPINC . '/class-wp-error.php'  );
+require( ABSPATH . WPINC . '/class-wp-plugin.php' );
+require( ABSPATH . WPINC . '/plugin.php'          );
+require( ABSPATH . WPINC . '/pomo/mo.php'         );
 
 // Include the wpdb class and, if present, a db.php database drop-in.
 require_wp_db();