Wordpress 3.6-scripts
[autoinstalls/wordpress.git] / wp-includes / query.php
index cf3cc1e29b38bc447118e4983446227956831c39..04286aa517cfc9fe5b180ae955811ed7503e202a 100644 (file)
@@ -2,8 +2,8 @@
 /**
  * WordPress Query API
  *
- * The query API attempts to get which part of WordPress to the user is on. It
- * also provides functionality to getting URL query information.
+ * The query API attempts to get which part of WordPress the user is on. It
+ * also provides functionality for getting URL query information.
  *
  * @link http://codex.wordpress.org/The_Loop More information on The Loop.
  *
@@ -27,6 +27,36 @@ function get_query_var($var) {
        return $wp_query->get($var);
 }
 
+/**
+ * Retrieve the currently-queried object. Wrapper for $wp_query->get_queried_object()
+ *
+ * @uses WP_Query::get_queried_object
+ *
+ * @since 3.1.0
+ * @access public
+ *
+ * @return object
+ */
+function get_queried_object() {
+       global $wp_query;
+       return $wp_query->get_queried_object();
+}
+
+/**
+ * Retrieve ID of the current queried object. Wrapper for $wp_query->get_queried_object_id()
+ *
+ * @uses WP_Query::get_queried_object_id()
+ *
+ * @since 3.1.0
+ * @access public
+ *
+ * @return int
+ */
+function get_queried_object_id() {
+       global $wp_query;
+       return $wp_query->get_queried_object_id();
+}
+
 /**
  * Set query variable.
  *
@@ -56,9 +86,8 @@ function set_query_var($var, $value) {
  * @param string $query
  * @return array List of posts
  */
-function &query_posts($query) {
-       unset($GLOBALS['wp_query']);
-       $GLOBALS['wp_query'] =& new WP_Query();
+function query_posts($query) {
+       $GLOBALS['wp_query'] = new WP_Query();
        return $GLOBALS['wp_query']->query($query);
 }
 
@@ -73,8 +102,7 @@ function &query_posts($query) {
  * @uses $wp_query
  */
 function wp_reset_query() {
-       unset($GLOBALS['wp_query']);
-       $GLOBALS['wp_query'] =& $GLOBALS['wp_the_query'];
+       $GLOBALS['wp_query'] = $GLOBALS['wp_the_query'];
        wp_reset_postdata();
 }
 
@@ -98,182 +126,173 @@ function wp_reset_postdata() {
  */
 
 /**
- * Is query requesting an archive page.
+ * Is the query for an existing archive page?
+ *
+ * Month, Year, Category, Author, Post Type archive...
  *
+ * @see WP_Query::is_archive()
  * @since 1.5.0
  * @uses $wp_query
  *
- * @return bool True if page is archive.
+ * @return bool
  */
 function is_archive() {
        global $wp_query;
 
-       return $wp_query->is_archive;
+       if ( ! isset( $wp_query ) ) {
+               _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1' );
+               return false;
+       }
+
+       return $wp_query->is_archive();
 }
 
 /**
- * Is query requesting an attachment page.
+ * Is the query for an existing post type archive page?
  *
- * @since 2.0.0
+ * @see WP_Query::is_post_type_archive()
+ * @since 3.1.0
  * @uses $wp_query
  *
- * @return bool True if page is attachment.
+ * @param mixed $post_types Optional. Post type or array of posts types to check against.
+ * @return bool
  */
-function is_attachment() {
+function is_post_type_archive( $post_types = '' ) {
        global $wp_query;
 
-       return $wp_query->is_attachment;
+       if ( ! isset( $wp_query ) ) {
+               _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1' );
+               return false;
+       }
+
+       return $wp_query->is_post_type_archive( $post_types );
 }
 
 /**
- * Is query requesting an author page.
+ * Is the query for an existing attachment page?
  *
- * If the $author parameter is specified then the check will be expanded to
- * include whether the queried author matches the one given in the parameter.
- * You can match against integers and against strings.
+ * @see WP_Query::is_attachment()
+ * @since 2.0.0
+ * @uses $wp_query
  *
- * If matching against an integer, the ID should be used of the author for the
- * test. If the $author is an ID and matches the author page user ID, then
- * 'true' will be returned.
+ * @return bool
+ */
+function is_attachment() {
+       global $wp_query;
+
+       if ( ! isset( $wp_query ) ) {
+               _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1' );
+               return false;
+       }
+
+       return $wp_query->is_attachment();
+}
+
+/**
+ * Is the query for an existing author archive page?
  *
- * If matching against strings, then the test will be matched against both the
- * nickname and user nicename and will return true on success.
+ * If the $author parameter is specified, this function will additionally
+ * check if the query is for one of the authors specified.
  *
+ * @see WP_Query::is_author()
  * @since 1.5.0
  * @uses $wp_query
  *
- * @param string|int $author Optional. Is current page this author.
- * @return bool True if page is author or $author (if set).
+ * @param mixed $author Optional. User ID, nickname, nicename, or array of User IDs, nicknames, and nicenames
+ * @return bool
  */
-function is_author($author = '') {
+function is_author( $author = '' ) {
        global $wp_query;
 
-       if ( !$wp_query->is_author )
+       if ( ! isset( $wp_query ) ) {
+               _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1' );
                return false;
+       }
 
-       if ( empty($author) )
-               return true;
-
-       $author_obj = $wp_query->get_queried_object();
-
-       $author = (array) $author;
-
-       if ( in_array( $author_obj->ID, $author ) )
-               return true;
-       elseif ( in_array( $author_obj->nickname, $author ) )
-               return true;
-       elseif ( in_array( $author_obj->user_nicename, $author ) )
-               return true;
-
-       return false;
+       return $wp_query->is_author( $author );
 }
 
 /**
- * Whether current page query contains a category name or given category name.
+ * Is the query for an existing category archive page?
  *
- * The category list can contain category IDs, names, or category slugs. If any
- * of them are part of the query, then it will return true.
+ * If the $category parameter is specified, this function will additionally
+ * check if the query is for one of the categories specified.
  *
+ * @see WP_Query::is_category()
  * @since 1.5.0
  * @uses $wp_query
  *
- * @param string|array $category Optional.
+ * @param mixed $category Optional. Category ID, name, slug, or array of Category IDs, names, and slugs.
  * @return bool
  */
-function is_category($category = '') {
+function is_category( $category = '' ) {
        global $wp_query;
 
-       if ( !$wp_query->is_category )
+       if ( ! isset( $wp_query ) ) {
+               _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1' );
                return false;
+       }
 
-       if ( empty($category) )
-               return true;
-
-       $cat_obj = $wp_query->get_queried_object();
-
-       $category = (array) $category;
-
-       if ( in_array( $cat_obj->term_id, $category ) )
-               return true;
-       elseif ( in_array( $cat_obj->name, $category ) )
-               return true;
-       elseif ( in_array( $cat_obj->slug, $category ) )
-               return true;
-
-       return false;
+       return $wp_query->is_category( $category );
 }
 
 /**
- * Whether the current page query has the given tag slug or contains tag.
+ * Is the query for an existing tag archive page?
  *
+ * If the $tag parameter is specified, this function will additionally
+ * check if the query is for one of the tags specified.
+ *
+ * @see WP_Query::is_tag()
  * @since 2.3.0
  * @uses $wp_query
  *
- * @param string|array $slug Optional. Single tag or list of tags to check for.
+ * @param mixed $slug Optional. Tag slug or array of slugs.
  * @return bool
  */
 function is_tag( $slug = '' ) {
        global $wp_query;
 
-       if ( !$wp_query->is_tag )
+       if ( ! isset( $wp_query ) ) {
+               _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1' );
                return false;
+       }
 
-       if ( empty( $slug ) )
-               return true;
-
-       $tag_obj = $wp_query->get_queried_object();
-
-       $slug = (array) $slug;
-
-       if ( in_array( $tag_obj->slug, $slug ) )
-               return true;
-
-       return false;
+       return $wp_query->is_tag( $slug );
 }
 
 /**
- * Whether the current query is for the given taxonomy and/or term.
+ * Is the query for an existing taxonomy archive page?
  *
- * If no taxonomy argument is set, returns true if any taxonomy is queried.
- * If the taxonomy argument is passed but no term argument, returns true
- *    if the taxonomy or taxonomies in the argument are being queried.
- * If both taxonomy and term arguments are passed, returns true
- *    if the current query is for a term contained in the terms argument
- *    which has a taxonomy contained in the taxonomy argument.
+ * If the $taxonomy parameter is specified, this function will additionally
+ * check if the query is for that specific $taxonomy.
  *
+ * If the $term parameter is specified in addition to the $taxonomy parameter,
+ * this function will additionally check if the query is for one of the terms
+ * specified.
+ *
+ * @see WP_Query::is_tax()
  * @since 2.5.0
  * @uses $wp_query
  *
- * @param string|array $taxonomy Optional. Taxonomy slug or slugs to check in current query.
- * @param int|array|string $term. Optional. A single or array of, The term's ID, Name or Slug
+ * @param mixed $taxonomy Optional. Taxonomy slug or slugs.
+ * @param mixed $term Optional. Term ID, name, slug or array of Term IDs, names, and slugs.
  * @return bool
  */
 function is_tax( $taxonomy = '', $term = '' ) {
-       global $wp_query, $wp_taxonomies;
-
-       $queried_object = $wp_query->get_queried_object();
-       $tax_array = array_intersect(array_keys($wp_taxonomies), (array) $taxonomy);
-       $term_array = (array) $term;
+       global $wp_query;
 
-       if ( !$wp_query->is_tax )
+       if ( ! isset( $wp_query ) ) {
+               _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1' );
                return false;
+       }
 
-       if ( empty( $taxonomy ) )
-               return true;
-
-       if ( empty( $term ) ) // Only a Taxonomy provided
-               return isset($queried_object->taxonomy) && count( $tax_array ) && in_array($queried_object->taxonomy, $tax_array);
-
-       return isset($queried_object->term_id) &&
-                       count(array_intersect(
-                               array($queried_object->term_id, $queried_object->name, $queried_object->slug),
-                               $term_array
-                       ));
+       return $wp_query->is_tax( $taxonomy, $term );
 }
 
 /**
  * Whether the current URL is within the comments popup window.
  *
+ * @see WP_Query::is_comments_popup()
  * @since 1.5.0
  * @uses $wp_query
  *
@@ -282,12 +301,18 @@ function is_tax( $taxonomy = '', $term = '' ) {
 function is_comments_popup() {
        global $wp_query;
 
-       return $wp_query->is_comments_popup;
+       if ( ! isset( $wp_query ) ) {
+               _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1' );
+               return false;
+       }
+
+       return $wp_query->is_comments_popup();
 }
 
 /**
- * Whether current URL is based on a date.
+ * Is the query for an existing date archive?
  *
+ * @see WP_Query::is_date()
  * @since 1.5.0
  * @uses $wp_query
  *
@@ -296,12 +321,18 @@ function is_comments_popup() {
 function is_date() {
        global $wp_query;
 
-       return $wp_query->is_date;
+       if ( ! isset( $wp_query ) ) {
+               _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1' );
+               return false;
+       }
+
+       return $wp_query->is_date();
 }
 
 /**
- * Whether current blog URL contains a day.
+ * Is the query for an existing day archive?
  *
+ * @see WP_Query::is_day()
  * @since 1.5.0
  * @uses $wp_query
  *
@@ -310,26 +341,39 @@ function is_date() {
 function is_day() {
        global $wp_query;
 
-       return $wp_query->is_day;
+       if ( ! isset( $wp_query ) ) {
+               _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1' );
+               return false;
+       }
+
+       return $wp_query->is_day();
 }
 
 /**
- * Whether current page query is feed URL.
+ * Is the query for a feed?
  *
+ * @see WP_Query::is_feed()
  * @since 1.5.0
  * @uses $wp_query
  *
+ * @param string|array $feeds Optional feed types to check.
  * @return bool
  */
-function is_feed() {
+function is_feed( $feeds = '' ) {
        global $wp_query;
 
-       return $wp_query->is_feed;
+       if ( ! isset( $wp_query ) ) {
+               _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1' );
+               return false;
+       }
+
+       return $wp_query->is_feed( $feeds );
 }
 
 /**
- * Whether current page query is comment feed URL.
+ * Is the query for a comments feed?
  *
+ * @see WP_Query::is_comments_feed()
  * @since 3.0.0
  * @uses $wp_query
  *
@@ -338,12 +382,27 @@ function is_feed() {
 function is_comment_feed() {
        global $wp_query;
 
-       return $wp_query->is_comment_feed;
+       if ( ! isset( $wp_query ) ) {
+               _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1' );
+               return false;
+       }
+
+       return $wp_query->is_comment_feed();
 }
 
 /**
- * Whether current page query is the front of the site.
+ * Is the query for the front page of the site?
  *
+ * This is for what is displayed at your site's main URL.
+ *
+ * Depends on the site's "Front page displays" Reading Settings 'show_on_front' and 'page_on_front'.
+ *
+ * If you set a static page for the front page of your site, this function will return
+ * true when viewing that page.
+ *
+ * Otherwise the same as @see is_home()
+ *
+ * @see WP_Query::is_front_page()
  * @since 2.5.0
  * @uses is_home()
  * @uses get_option()
@@ -351,22 +410,29 @@ function is_comment_feed() {
  * @return bool True, if front of site.
  */
 function is_front_page() {
-       // most likely case
-       if ( 'posts' == get_option('show_on_front') && is_home() )
-               return true;
-       elseif ( 'page' == get_option('show_on_front') && get_option('page_on_front') && is_page(get_option('page_on_front')) )
-               return true;
-       else
+       global $wp_query;
+
+       if ( ! isset( $wp_query ) ) {
+               _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1' );
                return false;
+       }
+
+       return $wp_query->is_front_page();
 }
 
 /**
- * Whether current page view is the blog homepage.
+ * Is the query for the blog homepage?
  *
- * This is the page which is showing the time based blog content of your site
- * so if you set a static page for the front page of your site then this will
- * only be true on the page which you set as the "Posts page" in Reading Settings.
+ * This is the page which shows the time based blog content of your site.
  *
+ * Depends on the site's "Front page displays" Reading Settings 'show_on_front' and 'page_for_posts'.
+ *
+ * If you set a static page for the front page of your site, this function will return
+ * true only on the page you set as the "Posts page".
+ *
+ * @see is_front_page()
+ *
+ * @see WP_Query::is_home()
  * @since 1.5.0
  * @uses $wp_query
  *
@@ -375,12 +441,18 @@ function is_front_page() {
 function is_home() {
        global $wp_query;
 
-       return $wp_query->is_home;
+       if ( ! isset( $wp_query ) ) {
+               _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1' );
+               return false;
+       }
+
+       return $wp_query->is_home();
 }
 
 /**
- * Whether current page query contains a month.
+ * Is the query for an existing month archive?
  *
+ * @see WP_Query::is_month()
  * @since 1.5.0
  * @uses $wp_query
  *
@@ -389,52 +461,45 @@ function is_home() {
 function is_month() {
        global $wp_query;
 
-       return $wp_query->is_month;
+       if ( ! isset( $wp_query ) ) {
+               _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1' );
+               return false;
+       }
+
+       return $wp_query->is_month();
 }
 
 /**
- * Whether query is page or contains given page(s).
+ * Is the query for an existing single page?
  *
- * Calls the function without any parameters will only test whether the current
- * query is of the page type. Either a list or a single item can be tested
- * against for whether the query is a page and also is the value or one of the
- * values in the page parameter.
+ * If the $page parameter is specified, this function will additionally
+ * check if the query is for one of the pages specified.
  *
- * The parameter can contain the page ID, page title, or page name. The
- * parameter can also be an array of those three values.
+ * @see is_single()
+ * @see is_singular()
  *
+ * @see WP_Query::is_page()
  * @since 1.5.0
  * @uses $wp_query
  *
- * @param mixed $page Either page or list of pages to test against.
+ * @param mixed $page Page ID, title, slug, or array of such.
  * @return bool
  */
-function is_page($page = '') {
+function is_page( $page = '' ) {
        global $wp_query;
 
-       if ( !$wp_query->is_page )
+       if ( ! isset( $wp_query ) ) {
+               _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1' );
                return false;
+       }
 
-       if ( empty($page) )
-               return true;
-
-       $page_obj = $wp_query->get_queried_object();
-
-       $page = (array) $page;
-
-       if ( in_array( $page_obj->ID, $page ) )
-               return true;
-       elseif ( in_array( $page_obj->post_title, $page ) )
-               return true;
-       else if ( in_array( $page_obj->post_name, $page ) )
-               return true;
-
-       return false;
+       return $wp_query->is_page( $page );
 }
 
 /**
- * Whether query contains multiple pages for the results.
+ * Is the query for paged result and not for the first page?
  *
+ * @see WP_Query::is_paged()
  * @since 1.5.0
  * @uses $wp_query
  *
@@ -443,32 +508,18 @@ function is_page($page = '') {
 function is_paged() {
        global $wp_query;
 
-       return $wp_query->is_paged;
-}
-
-/**
- * Whether the current page was created by a plugin.
- *
- * The plugin can set this by using the global $plugin_page and setting it to
- * true.
- *
- * @since 1.5.0
- * @global bool $plugin_page Used by plugins to tell the query that current is a plugin page.
- *
- * @return bool
- */
-function is_plugin_page() {
-       global $plugin_page;
-
-       if ( isset($plugin_page) )
-               return true;
+       if ( ! isset( $wp_query ) ) {
+               _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1' );
+               return false;
+       }
 
-       return false;
+       return $wp_query->is_paged();
 }
 
 /**
- * Whether the current query is preview of post or page.
+ * Is the query for a post or page preview?
  *
+ * @see WP_Query::is_preview()
  * @since 2.0.0
  * @uses $wp_query
  *
@@ -477,12 +528,18 @@ function is_plugin_page() {
 function is_preview() {
        global $wp_query;
 
-       return $wp_query->is_preview;
+       if ( ! isset( $wp_query ) ) {
+               _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1' );
+               return false;
+       }
+
+       return $wp_query->is_preview();
 }
 
 /**
- * Whether the current query post is robots.
+ * Is the query for the robots file?
  *
+ * @see WP_Query::is_robots()
  * @since 2.1.0
  * @uses $wp_query
  *
@@ -491,12 +548,18 @@ function is_preview() {
 function is_robots() {
        global $wp_query;
 
-       return $wp_query->is_robots;
+       if ( ! isset( $wp_query ) ) {
+               _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1' );
+               return false;
+       }
+
+       return $wp_query->is_robots();
 }
 
 /**
- * Whether current query is the result of a user search.
+ * Is the query for a search?
  *
+ * @see WP_Query::is_search()
  * @since 1.5.0
  * @uses $wp_query
  *
@@ -505,70 +568,74 @@ function is_robots() {
 function is_search() {
        global $wp_query;
 
-       return $wp_query->is_search;
+       if ( ! isset( $wp_query ) ) {
+               _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1' );
+               return false;
+       }
+
+       return $wp_query->is_search();
 }
 
 /**
- * Whether the current page query is single page.
+ * Is the query for an existing single post?
+ *
+ * Works for any post type, except attachments and pages
  *
- * The parameter can contain the post ID, post title, or post name. The
- * parameter can also be an array of those three values.
+ * If the $post parameter is specified, this function will additionally
+ * check if the query is for one of the Posts specified.
  *
- * This applies to other post types, attachments, pages, posts. Just means that
- * the current query has only a single object.
+ * @see is_page()
+ * @see is_singular()
  *
+ * @see WP_Query::is_single()
  * @since 1.5.0
  * @uses $wp_query
  *
- * @param mixed $post Either post or list of posts to test against.
+ * @param mixed $post Post ID, title, slug, or array of such.
  * @return bool
  */
-function is_single($post = '') {
+function is_single( $post = '' ) {
        global $wp_query;
 
-       if ( !$wp_query->is_single )
+       if ( ! isset( $wp_query ) ) {
+               _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1' );
                return false;
+       }
 
-       if ( empty($post) )
-               return true;
-
-       $post_obj = $wp_query->get_queried_object();
-
-       $post = (array) $post;
-
-       if ( in_array( $post_obj->ID, $post ) )
-               return true;
-       elseif ( in_array( $post_obj->post_title, $post ) )
-               return true;
-       elseif ( in_array( $post_obj->post_name, $post ) )
-               return true;
-
-       return false;
+       return $wp_query->is_single( $post );
 }
 
 /**
- * Whether is single post, is a page, or is an attachment.
+ * Is the query for an existing single post of any post type (post, attachment, page, ... )?
+ *
+ * If the $post_types parameter is specified, this function will additionally
+ * check if the query is for one of the Posts Types specified.
  *
+ * @see is_page()
+ * @see is_single()
+ *
+ * @see WP_Query::is_singular()
  * @since 1.5.0
  * @uses $wp_query
  *
- * @param string|array $post_types Optional. Post type or types to check in current query.
+ * @param mixed $post_types Optional. Post Type or array of Post Types
  * @return bool
  */
-function is_singular($post_types = '') {
+function is_singular( $post_types = '' ) {
        global $wp_query;
 
-       if ( empty($post_types) || !$wp_query->is_singular )
-               return $wp_query->is_singular;
-
-       $post_obj = $wp_query->get_queried_object();
+       if ( ! isset( $wp_query ) ) {
+               _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1' );
+               return false;
+       }
 
-       return in_array($post_obj->post_type, (array) $post_types);
+       return $wp_query->is_singular( $post_types );
 }
 
 /**
- * Whether the query contains a time.
+ * Is the query for a specific time?
  *
+ * @see WP_Query::is_time()
  * @since 1.5.0
  * @uses $wp_query
  *
@@ -577,12 +644,18 @@ function is_singular($post_types = '') {
 function is_time() {
        global $wp_query;
 
-       return $wp_query->is_time;
+       if ( ! isset( $wp_query ) ) {
+               _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1' );
+               return false;
+       }
+
+       return $wp_query->is_time();
 }
 
 /**
- * Whether the query is a trackback.
+ * Is the query for a trackback endpoint call?
  *
+ * @see WP_Query::is_trackback()
  * @since 1.5.0
  * @uses $wp_query
  *
@@ -591,12 +664,18 @@ function is_time() {
 function is_trackback() {
        global $wp_query;
 
-       return $wp_query->is_trackback;
+       if ( ! isset( $wp_query ) ) {
+               _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1' );
+               return false;
+       }
+
+       return $wp_query->is_trackback();
 }
 
 /**
- * Whether the query contains a year.
+ * Is the query for an existing year archive?
  *
+ * @see WP_Query::is_year()
  * @since 1.5.0
  * @uses $wp_query
  *
@@ -605,25 +684,48 @@ function is_trackback() {
 function is_year() {
        global $wp_query;
 
-       return $wp_query->is_year;
+       if ( ! isset( $wp_query ) ) {
+               _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1' );
+               return false;
+       }
+
+       return $wp_query->is_year();
 }
 
 /**
- * Whether current page query is a 404 and no results for WordPress query.
+ * Is the query a 404 (returns no results)?
  *
+ * @see WP_Query::is_404()
  * @since 1.5.0
  * @uses $wp_query
  *
- * @return bool True, if nothing is found matching WordPress Query.
+ * @return bool
  */
 function is_404() {
        global $wp_query;
 
-       return $wp_query->is_404;
+       if ( ! isset( $wp_query ) ) {
+               _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1' );
+               return false;
+       }
+
+       return $wp_query->is_404();
+}
+
+/**
+ * Is the query the main query?
+ *
+ * @since 3.3.0
+ *
+ * @return bool
+ */
+function is_main_query() {
+       global $wp_query;
+       return $wp_query->is_main_query();
 }
 
 /*
- * The Loop.  Post loop control.
+ * The Loop. Post loop control.
  */
 
 /**
@@ -729,16 +831,16 @@ function the_comment() {
 class WP_Query {
 
        /**
-        * Query string
+        * Query vars set by the user
         *
         * @since 1.5.0
         * @access public
-        * @var string
+        * @var array
         */
        var $query;
 
        /**
-        * Query search variables set by the user.
+        * Query vars, after parsing
         *
         * @since 1.5.0
         * @access public
@@ -746,6 +848,24 @@ class WP_Query {
         */
        var $query_vars = array();
 
+       /**
+        * Taxonomy query, as passed to get_tax_sql()
+        *
+        * @since 3.1.0
+        * @access public
+        * @var object WP_Tax_Query
+        */
+       var $tax_query;
+
+       /**
+        * Metadata query container
+        *
+        * @since 3.2.0
+        * @access public
+        * @var object WP_Meta_Query
+        */
+       var $meta_query = false;
+
        /**
         * Holds the data for a single object that is queried.
         *
@@ -816,7 +936,7 @@ class WP_Query {
         *
         * @since 1.5.0
         * @access public
-        * @var int
+        * @var object
         */
        var $post;
 
@@ -857,7 +977,9 @@ class WP_Query {
        var $comment;
 
        /**
-        * Amount of posts if limit clause was not used.
+        * The amount of found posts for the current query.
+        *
+        * If limit clause was not used, equals $post_count.
         *
         * @since 2.1.0
         * @access public
@@ -1063,6 +1185,15 @@ class WP_Query {
         */
        var $is_comments_popup = false;
 
+       /**
+        * Set if query is paged
+        *
+        * @since 1.5.0
+        * @access public
+        * @var bool
+        */
+       var $is_paged = false;
+
        /**
         * Set if query is part of administration page.
         *
@@ -1110,6 +1241,42 @@ class WP_Query {
         */
        var $is_posts_page = false;
 
+       /**
+        * Set if query is for a post type archive.
+        *
+        * @since 3.1.0
+        * @access public
+        * @var bool
+        */
+       var $is_post_type_archive = false;
+
+       /**
+        * Stores the ->query_vars state like md5(serialize( $this->query_vars ) ) so we know
+        * whether we have to re-parse because something has changed
+        *
+        * @since 3.1.0
+        * @access private
+        */
+       var $query_vars_hash = false;
+
+       /**
+        * Whether query vars have changed since the initial parse_query() call. Used to catch modifications to query vars made
+        * via pre_get_posts hooks.
+        *
+        * @since 3.1.1
+        * @access private
+        */
+       var $query_vars_changed = true;
+
+       /**
+        * Set if post thumbnails are cached
+        *
+        * @since 3.2.0
+        * @access public
+        * @var bool
+        */
+        var $thumbnails_cached = false;
+
        /**
         * Resets query flags to false.
         *
@@ -1120,6 +1287,7 @@ class WP_Query {
         */
        function init_query_flags() {
                $this->is_single = false;
+               $this->is_preview = false;
                $this->is_page = false;
                $this->is_archive = false;
                $this->is_date = false;
@@ -1137,12 +1305,14 @@ class WP_Query {
                $this->is_trackback = false;
                $this->is_home = false;
                $this->is_404 = false;
+               $this->is_comments_popup = false;
                $this->is_paged = false;
                $this->is_admin = false;
                $this->is_attachment = false;
                $this->is_singular = false;
                $this->is_robots = false;
                $this->is_posts_page = false;
+               $this->is_post_type_archive = false;
        }
 
        /**
@@ -1160,6 +1330,15 @@ class WP_Query {
                $this->post_count = 0;
                $this->current_post = -1;
                $this->in_the_loop = false;
+               unset( $this->request );
+               unset( $this->post );
+               unset( $this->comments );
+               unset( $this->comment );
+               $this->comment_count = 0;
+               $this->current_comment = -1;
+               $this->found_posts = 0;
+               $this->max_num_pages = 0;
+               $this->max_num_comment_pages = 0;
 
                $this->init_query_flags();
        }
@@ -1171,7 +1350,7 @@ class WP_Query {
         * @access public
         */
        function parse_query_vars() {
-               $this->parse_query('');
+               $this->parse_query();
        }
 
        /**
@@ -1218,18 +1397,20 @@ class WP_Query {
                        , 'preview'
                        , 's'
                        , 'sentence'
+                       , 'fields'
+                       , 'menu_order'
                );
 
                foreach ( $keys as $key ) {
-                       if ( !isset($array[$key]))
+                       if ( !isset($array[$key]) )
                                $array[$key] = '';
                }
 
-               $array_keys = array('category__in', 'category__not_in', 'category__and', 'post__in', 'post__not_in',
-                       'tag__in', 'tag__not_in', 'tag__and', 'tag_slug__in', 'tag_slug__and');
+               $array_keys = array( 'category__in', 'category__not_in', 'category__and', 'post__in', 'post__not_in',
+                       'tag__in', 'tag__not_in', 'tag__and', 'tag_slug__in', 'tag_slug__and', 'post_parent__in', 'post_parent__not_in' );
 
                foreach ( $array_keys as $key ) {
-                       if ( !isset($array[$key]))
+                       if ( !isset($array[$key]) )
                                $array[$key] = array();
                }
                return $array;
@@ -1241,20 +1422,19 @@ class WP_Query {
         * @since 1.5.0
         * @access public
         *
-        * @param string|array $query
+        * @param string|array $query Optional query.
         */
-       function parse_query($query) {
-               if ( !empty($query) || !isset($this->query) ) {
+       function parse_query( $query =  '' ) {
+               if ( ! empty( $query ) ) {
                        $this->init();
-                       if ( is_array($query) )
-                               $this->query_vars = $query;
-                       else
-                               parse_str($query, $this->query_vars);
-                       $this->query = $query;
+                       $this->query = $this->query_vars = wp_parse_args( $query );
+               } elseif ( ! isset( $this->query ) ) {
+                       $this->query = $this->query_vars;
                }
 
                $this->query_vars = $this->fill_query_vars($this->query_vars);
                $qv = &$this->query_vars;
+               $this->query_vars_changed = true;
 
                if ( ! empty($qv['robots']) )
                        $this->is_robots = true;
@@ -1273,8 +1453,9 @@ class WP_Query {
                if ( '' !== $qv['hour'] ) $qv['hour'] = absint($qv['hour']);
                if ( '' !== $qv['minute'] ) $qv['minute'] = absint($qv['minute']);
                if ( '' !== $qv['second'] ) $qv['second'] = absint($qv['second']);
+               if ( '' !== $qv['menu_order'] ) $qv['menu_order'] = absint($qv['menu_order']);
 
-               // Compat.  Map subpost to attachment.
+               // Compat. Map subpost to attachment.
                if ( '' != $qv['subpost'] )
                        $qv['attachment'] = $qv['subpost'];
                if ( '' != $qv['subpost_id'] )
@@ -1296,10 +1477,12 @@ class WP_Query {
                } elseif ( '' != $qv['static'] || '' != $qv['pagename'] || !empty($qv['page_id']) ) {
                        $this->is_page = true;
                        $this->is_single = false;
-               } elseif ( !empty($qv['s']) ) {
-                       $this->is_search = true;
                } else {
-               // Look for archive queries.  Dates, categories, authors.
+               // Look for archive queries. Dates, categories, authors, search, post type archives.
+
+                       if ( !empty($qv['s']) ) {
+                               $this->is_search = true;
+                       }
 
                        if ( '' !== $qv['second'] ) {
                                $this->is_time = true;
@@ -1354,94 +1537,24 @@ class WP_Query {
                                $this->is_date = true;
                        }
 
-                       if ( empty($qv['cat']) || ($qv['cat'] == '0') ) {
-                               $this->is_category = false;
-                       } else {
-                               if ( strpos($qv['cat'], '-') !== false ) {
-                                       $this->is_category = false;
-                               } else {
-                                       $this->is_category = true;
-                               }
-                       }
-
-                       if ( '' != $qv['category_name'] ) {
-                               $this->is_category = true;
-                       }
-
-                       if ( !is_array($qv['category__in']) || empty($qv['category__in']) ) {
-                               $qv['category__in'] = array();
-                       } else {
-                               $qv['category__in'] = array_map('absint', $qv['category__in']);
-                               $this->is_category = true;
-                       }
-
-                       if ( !is_array($qv['category__not_in']) || empty($qv['category__not_in']) ) {
-                               $qv['category__not_in'] = array();
-                       } else {
-                               $qv['category__not_in'] = array_map('absint', $qv['category__not_in']);
-                       }
-
-                       if ( !is_array($qv['category__and']) || empty($qv['category__and']) ) {
-                               $qv['category__and'] = array();
-                       } else {
-                               $qv['category__and'] = array_map('absint', $qv['category__and']);
-                               $this->is_category = true;
-                       }
-
-                       if (  '' != $qv['tag'] )
-                               $this->is_tag = true;
-
-                       $qv['tag_id'] = absint($qv['tag_id']);
-                       if (  !empty($qv['tag_id']) )
-                               $this->is_tag = true;
-
-                       if ( !is_array($qv['tag__in']) || empty($qv['tag__in']) ) {
-                               $qv['tag__in'] = array();
-                       } else {
-                               $qv['tag__in'] = array_map('absint', $qv['tag__in']);
-                               $this->is_tag = true;
-                       }
-
-                       if ( !is_array($qv['tag__not_in']) || empty($qv['tag__not_in']) ) {
-                               $qv['tag__not_in'] = array();
-                       } else {
-                               $qv['tag__not_in'] = array_map('absint', $qv['tag__not_in']);
-                       }
-
-                       if ( !is_array($qv['tag__and']) || empty($qv['tag__and']) ) {
-                               $qv['tag__and'] = array();
-                       } else {
-                               $qv['tag__and'] = array_map('absint', $qv['tag__and']);
-                               $this->is_category = true;
-                       }
-
-                       if ( !is_array($qv['tag_slug__in']) || empty($qv['tag_slug__in']) ) {
-                               $qv['tag_slug__in'] = array();
-                       } else {
-                               $qv['tag_slug__in'] = array_map('sanitize_title', $qv['tag_slug__in']);
-                               $this->is_tag = true;
-                       }
-
-                       if ( !is_array($qv['tag_slug__and']) || empty($qv['tag_slug__and']) ) {
-                               $qv['tag_slug__and'] = array();
-                       } else {
-                               $qv['tag_slug__and'] = array_map('sanitize_title', $qv['tag_slug__and']);
-                               $this->is_tag = true;
-                       }
+                       $this->query_vars_hash = false;
+                       $this->parse_tax_query( $qv );
 
-                       if ( empty($qv['taxonomy']) || empty($qv['term']) ) {
-                               $this->is_tax = false;
-                               foreach ( $GLOBALS['wp_taxonomies'] as $taxonomy => $t ) {
-                                       if ( $t->query_var && isset($qv[$t->query_var]) && '' != $qv[$t->query_var] ) {
-                                               $qv['taxonomy'] = $taxonomy;
-                                               $qv['term'] = $qv[$t->query_var];
-                                               $this->is_tax = true;
-                                               break;
+                       foreach ( $this->tax_query->queries as $tax_query ) {
+                               if ( 'NOT IN' != $tax_query['operator'] ) {
+                                       switch ( $tax_query['taxonomy'] ) {
+                                               case 'category':
+                                                       $this->is_category = true;
+                                                       break;
+                                               case 'post_tag':
+                                                       $this->is_tag = true;
+                                                       break;
+                                               default:
+                                                       $this->is_tax = true;
                                        }
                                }
-                       } else {
-                               $this->is_tax = true;
                        }
+                       unset( $tax_query );
 
                        if ( empty($qv['author']) || ($qv['author'] == '0') ) {
                                $this->is_author = false;
@@ -1449,11 +1562,16 @@ class WP_Query {
                                $this->is_author = true;
                        }
 
-                       if ( '' != $qv['author_name'] ) {
+                       if ( '' != $qv['author_name'] )
                                $this->is_author = true;
+
+                       if ( !empty( $qv['post_type'] ) && ! is_array( $qv['post_type'] ) ) {
+                               $post_type_obj = get_post_type_object( $qv['post_type'] );
+                               if ( ! empty( $post_type_obj->has_archive ) )
+                                       $this->is_post_type_archive = true;
                        }
 
-                       if ( ($this->is_date || $this->is_author || $this->is_category || $this->is_tag || $this->is_tax) )
+                       if ( $this->is_post_type_archive || $this->is_date || $this->is_author || $this->is_category || $this->is_tag || $this->is_tax )
                                $this->is_archive = true;
                }
 
@@ -1491,7 +1609,10 @@ class WP_Query {
 
                // Correct is_* for page_on_front and page_for_posts
                if ( $this->is_home && 'page' == get_option('show_on_front') && get_option('page_on_front') ) {
-                       $_query = wp_parse_args($query);
+                       $_query = wp_parse_args($this->query);
+                       // pagename can be set and empty depending on matched rewrite rules. Ignore an empty pagename.
+                       if ( isset($_query['pagename']) && '' == $_query['pagename'] )
+                               unset($_query['pagename']);
                        if ( empty($_query) || !array_diff( array_keys($_query), array('preview', 'page', 'paged', 'cpage') ) ) {
                                $this->is_page = true;
                                $this->is_home = false;
@@ -1505,7 +1626,7 @@ class WP_Query {
                }
 
                if ( '' != $qv['pagename'] ) {
-                       $this->queried_object =& get_page_by_path($qv['pagename']);
+                       $this->queried_object = get_page_by_path($qv['pagename']);
                        if ( !empty($this->queried_object) )
                                $this->queried_object_id = (int) $this->queried_object->ID;
                        else
@@ -1528,13 +1649,17 @@ class WP_Query {
 
                if ( !empty($qv['post_type']) ) {
                        if ( is_array($qv['post_type']) )
-                               $qv['post_type'] = array_map('sanitize_user', $qv['post_type'], array(true));
+                               $qv['post_type'] = array_map('sanitize_key', $qv['post_type']);
                        else
-                               $qv['post_type'] = sanitize_user($qv['post_type'], true);
+                               $qv['post_type'] = sanitize_key($qv['post_type']);
                }
 
-               if ( !empty($qv['post_status']) )
-                       $qv['post_status'] = preg_replace('|[^a-z0-9_,-]|', '', $qv['post_status']);
+               if ( ! empty( $qv['post_status'] ) ) {
+                       if ( is_array( $qv['post_status'] ) )
+                               $qv['post_status'] = array_map('sanitize_key', $qv['post_status']);
+                       else
+                               $qv['post_status'] = preg_replace('|[^a-z0-9_,-]|', '', $qv['post_status']);
+               }
 
                if ( $this->is_posts_page && ( ! isset($qv['withcomments']) || ! $qv['withcomments'] ) )
                        $this->is_comment_feed = false;
@@ -1545,24 +1670,210 @@ class WP_Query {
                if ( '404' == $qv['error'] )
                        $this->set_404();
 
-               if ( !empty($query) )
-                       do_action_ref_array('parse_query', array(&$this));
+               $this->query_vars_hash = md5( serialize( $this->query_vars ) );
+               $this->query_vars_changed = false;
+
+               do_action_ref_array('parse_query', array(&$this));
        }
 
-       /**
-        * Sets the 404 property and saves whether query is feed.
+       /*
+        * Parses various taxonomy related query vars.
         *
-        * @since 2.0.0
-        * @access public
+        * @access protected
+        * @since 3.1.0
+        *
+        * @param array &$q The query variables
         */
-       function set_404() {
-               $is_feed = $this->is_feed;
+       function parse_tax_query( &$q ) {
+               if ( ! empty( $q['tax_query'] ) && is_array( $q['tax_query'] ) ) {
+                       $tax_query = $q['tax_query'];
+               } else {
+                       $tax_query = array();
+               }
 
-               $this->init_query_flags();
-               $this->is_404 = true;
+               if ( !empty($q['taxonomy']) && !empty($q['term']) ) {
+                       $tax_query[] = array(
+                               'taxonomy' => $q['taxonomy'],
+                               'terms' => array( $q['term'] ),
+                               'field' => 'slug',
+                       );
+               }
 
-               $this->is_feed = $is_feed;
-       }
+               foreach ( $GLOBALS['wp_taxonomies'] as $taxonomy => $t ) {
+                       if ( 'post_tag' == $taxonomy )
+                               continue;       // Handled further down in the $q['tag'] block
+
+                       if ( $t->query_var && !empty( $q[$t->query_var] ) ) {
+                               $tax_query_defaults = array(
+                                       'taxonomy' => $taxonomy,
+                                       'field' => 'slug',
+                               );
+
+                               if ( isset( $t->rewrite['hierarchical'] ) && $t->rewrite['hierarchical'] ) {
+                                       $q[$t->query_var] = wp_basename( $q[$t->query_var] );
+                               }
+
+                               $term = $q[$t->query_var];
+
+                               if ( strpos($term, '+') !== false ) {
+                                       $terms = preg_split( '/[+]+/', $term );
+                                       foreach ( $terms as $term ) {
+                                               $tax_query[] = array_merge( $tax_query_defaults, array(
+                                                       'terms' => array( $term )
+                                               ) );
+                                       }
+                               } else {
+                                       $tax_query[] = array_merge( $tax_query_defaults, array(
+                                               'terms' => preg_split( '/[,]+/', $term )
+                                       ) );
+                               }
+                       }
+               }
+
+               // Category stuff
+               if ( !empty($q['cat']) && '0' != $q['cat'] && !$this->is_singular && $this->query_vars_changed ) {
+                       $q['cat'] = ''.urldecode($q['cat']).'';
+                       $q['cat'] = addslashes_gpc($q['cat']);
+                       $cat_array = preg_split('/[,\s]+/', $q['cat']);
+                       $q['cat'] = '';
+                       $req_cats = array();
+                       foreach ( (array) $cat_array as $cat ) {
+                               $cat = intval($cat);
+                               $req_cats[] = $cat;
+                               $in = ($cat > 0);
+                               $cat = abs($cat);
+                               if ( $in ) {
+                                       $q['category__in'][] = $cat;
+                                       $q['category__in'] = array_merge( $q['category__in'], get_term_children($cat, 'category') );
+                               } else {
+                                       $q['category__not_in'][] = $cat;
+                                       $q['category__not_in'] = array_merge( $q['category__not_in'], get_term_children($cat, 'category') );
+                               }
+                       }
+                       $q['cat'] = implode(',', $req_cats);
+               }
+
+               if ( !empty($q['category__in']) ) {
+                       $q['category__in'] = array_map('absint', array_unique( (array) $q['category__in'] ) );
+                       $tax_query[] = array(
+                               'taxonomy' => 'category',
+                               'terms' => $q['category__in'],
+                               'field' => 'term_id',
+                               'include_children' => false
+                       );
+               }
+
+               if ( !empty($q['category__not_in']) ) {
+                       $q['category__not_in'] = array_map('absint', array_unique( (array) $q['category__not_in'] ) );
+                       $tax_query[] = array(
+                               'taxonomy' => 'category',
+                               'terms' => $q['category__not_in'],
+                               'operator' => 'NOT IN',
+                               'include_children' => false
+                       );
+               }
+
+               if ( !empty($q['category__and']) ) {
+                       $q['category__and'] = array_map('absint', array_unique( (array) $q['category__and'] ) );
+                       $tax_query[] = array(
+                               'taxonomy' => 'category',
+                               'terms' => $q['category__and'],
+                               'field' => 'term_id',
+                               'operator' => 'AND',
+                               'include_children' => false
+                       );
+               }
+
+               // Tag stuff
+               if ( '' != $q['tag'] && !$this->is_singular && $this->query_vars_changed ) {
+                       if ( strpos($q['tag'], ',') !== false ) {
+                               $tags = preg_split('/[,\r\n\t ]+/', $q['tag']);
+                               foreach ( (array) $tags as $tag ) {
+                                       $tag = sanitize_term_field('slug', $tag, 0, 'post_tag', 'db');
+                                       $q['tag_slug__in'][] = $tag;
+                               }
+                       } else if ( preg_match('/[+\r\n\t ]+/', $q['tag']) || !empty($q['cat']) ) {
+                               $tags = preg_split('/[+\r\n\t ]+/', $q['tag']);
+                               foreach ( (array) $tags as $tag ) {
+                                       $tag = sanitize_term_field('slug', $tag, 0, 'post_tag', 'db');
+                                       $q['tag_slug__and'][] = $tag;
+                               }
+                       } else {
+                               $q['tag'] = sanitize_term_field('slug', $q['tag'], 0, 'post_tag', 'db');
+                               $q['tag_slug__in'][] = $q['tag'];
+                       }
+               }
+
+               if ( !empty($q['tag_id']) ) {
+                       $q['tag_id'] = absint( $q['tag_id'] );
+                       $tax_query[] = array(
+                               'taxonomy' => 'post_tag',
+                               'terms' => $q['tag_id']
+                       );
+               }
+
+               if ( !empty($q['tag__in']) ) {
+                       $q['tag__in'] = array_map('absint', array_unique( (array) $q['tag__in'] ) );
+                       $tax_query[] = array(
+                               'taxonomy' => 'post_tag',
+                               'terms' => $q['tag__in']
+                       );
+               }
+
+               if ( !empty($q['tag__not_in']) ) {
+                       $q['tag__not_in'] = array_map('absint', array_unique( (array) $q['tag__not_in'] ) );
+                       $tax_query[] = array(
+                               'taxonomy' => 'post_tag',
+                               'terms' => $q['tag__not_in'],
+                               'operator' => 'NOT IN'
+                       );
+               }
+
+               if ( !empty($q['tag__and']) ) {
+                       $q['tag__and'] = array_map('absint', array_unique( (array) $q['tag__and'] ) );
+                       $tax_query[] = array(
+                               'taxonomy' => 'post_tag',
+                               'terms' => $q['tag__and'],
+                               'operator' => 'AND'
+                       );
+               }
+
+               if ( !empty($q['tag_slug__in']) ) {
+                       $q['tag_slug__in'] = array_map('sanitize_title_for_query', array_unique( (array) $q['tag_slug__in'] ) );
+                       $tax_query[] = array(
+                               'taxonomy' => 'post_tag',
+                               'terms' => $q['tag_slug__in'],
+                               'field' => 'slug'
+                       );
+               }
+
+               if ( !empty($q['tag_slug__and']) ) {
+                       $q['tag_slug__and'] = array_map('sanitize_title_for_query', array_unique( (array) $q['tag_slug__and'] ) );
+                       $tax_query[] = array(
+                               'taxonomy' => 'post_tag',
+                               'terms' => $q['tag_slug__and'],
+                               'field' => 'slug',
+                               'operator' => 'AND'
+                       );
+               }
+
+               $this->tax_query = new WP_Tax_Query( $tax_query );
+       }
+
+       /**
+        * Sets the 404 property and saves whether query is feed.
+        *
+        * @since 2.0.0
+        * @access public
+        */
+       function set_404() {
+               $is_feed = $this->is_feed;
+
+               $this->init_query_flags();
+               $this->is_404 = true;
+
+               $this->is_feed = $is_feed;
+       }
 
        /**
         * Retrieve query variable.
@@ -1605,19 +1916,33 @@ class WP_Query {
         *
         * @return array List of posts.
         */
-       function &get_posts() {
+       function get_posts() {
                global $wpdb, $user_ID, $_wp_using_ext_object_cache;
 
+               $this->parse_query();
+
                do_action_ref_array('pre_get_posts', array(&$this));
 
                // Shorthand.
                $q = &$this->query_vars;
 
+               // Fill again in case pre_get_posts unset some vars.
                $q = $this->fill_query_vars($q);
 
+               // Parse meta query
+               $this->meta_query = new WP_Meta_Query();
+               $this->meta_query->parse_query_vars( $q );
+
+               // Set a flag if a pre_get_posts hook changed the query vars.
+               $hash = md5( serialize( $this->query_vars ) );
+               if ( $hash != $this->query_vars_hash ) {
+                       $this->query_vars_changed = true;
+                       $this->query_vars_hash = $hash;
+               }
+               unset($hash);
+
                // First let's clear some variables
                $distinct = '';
-               $whichcat = '';
                $whichauthor = '';
                $whichmimetype = '';
                $where = '';
@@ -1625,12 +1950,18 @@ class WP_Query {
                $join = '';
                $search = '';
                $groupby = '';
-               $fields = "$wpdb->posts.*";
+               $fields = '';
                $post_status_join = false;
                $page = 1;
 
-               if ( !isset($q['caller_get_posts']) )
-                       $q['caller_get_posts'] = false;
+               if ( isset( $q['caller_get_posts'] ) ) {
+                       _deprecated_argument( 'WP_Query', '3.1', __( '"caller_get_posts" is deprecated. Use "ignore_sticky_posts" instead.' ) );
+                       if ( !isset( $q['ignore_sticky_posts'] ) )
+                               $q['ignore_sticky_posts'] = $q['caller_get_posts'];
+               }
+
+               if ( !isset( $q['ignore_sticky_posts'] ) )
+                       $q['ignore_sticky_posts'] = false;
 
                if ( !isset($q['suppress_filters']) )
                        $q['suppress_filters'] = false;
@@ -1700,6 +2031,20 @@ class WP_Query {
                else
                        $q['no_found_rows'] = false;
 
+               switch ( $q['fields'] ) {
+                       case 'ids':
+                               $fields = "$wpdb->posts.ID";
+                               break;
+                       case 'id=>parent':
+                               $fields = "$wpdb->posts.ID, $wpdb->posts.post_parent";
+                               break;
+                       default:
+                               $fields = "$wpdb->posts.*";
+               }
+
+               if ( '' !== $q['menu_order'] )
+                       $where .= " AND $wpdb->posts.menu_order = " . $q['menu_order'];
+
                // If a month is specified in the querystring, load that month
                if ( $q['m'] ) {
                        $q['m'] = '' . preg_replace('|[^0-9]|', '', $q['m']);
@@ -1734,7 +2079,7 @@ class WP_Query {
                if ( $q['day'] )
                        $where .= " AND DAYOFMONTH($wpdb->posts.post_date)='" . $q['day'] . "'";
 
-               // If we've got a post_type AND its not "any" post_type.
+               // If we've got a post_type AND it's not "any" post_type.
                if ( !empty($q['post_type']) && 'any' != $q['post_type'] ) {
                        foreach ( (array)$q['post_type'] as $_post_type ) {
                                $ptype_obj = get_post_type_object($_post_type);
@@ -1757,7 +2102,7 @@ class WP_Query {
                }
 
                if ( '' != $q['name'] ) {
-                       $q['name'] = sanitize_title($q['name']);
+                       $q['name'] = sanitize_title_for_query( $q['name'] );
                        $where .= " AND $wpdb->posts.post_name = '" . $q['name'] . "'";
                } elseif ( '' != $q['pagename'] ) {
                        if ( isset($this->queried_object_id) ) {
@@ -1785,12 +2130,10 @@ class WP_Query {
 
                        $page_for_posts = get_option('page_for_posts');
                        if  ( ('page' != get_option('show_on_front') ) || empty($page_for_posts) || ( $reqpage != $page_for_posts ) ) {
-                               $q['pagename'] = str_replace('%2F', '/', urlencode(urldecode($q['pagename'])));
-                               $page_paths = '/' . trim($q['pagename'], '/');
-                               $q['pagename'] = sanitize_title(basename($page_paths));
+                               $q['pagename'] = sanitize_title_for_query( wp_basename( $q['pagename'] ) );
                                $q['name'] = $q['pagename'];
                                $where .= " AND ($wpdb->posts.ID = '$reqpage')";
-                               $reqpage_obj = get_page($reqpage);
+                               $reqpage_obj = get_post( $reqpage );
                                if ( is_object($reqpage_obj) && 'attachment' == $reqpage_obj->post_type ) {
                                        $this->is_attachment = true;
                                        $post_type = $q['post_type'] = 'attachment';
@@ -1799,9 +2142,7 @@ class WP_Query {
                                }
                        }
                } elseif ( '' != $q['attachment'] ) {
-                       $q['attachment'] = str_replace('%2F', '/', urlencode(urldecode($q['attachment'])));
-                       $attach_paths = '/' . trim($q['attachment'], '/');
-                       $q['attachment'] = sanitize_title(basename($attach_paths));
+                       $q['attachment'] = sanitize_title_for_query( wp_basename( $q['attachment'] ) );
                        $q['name'] = $q['attachment'];
                        $where .= " AND $wpdb->posts.post_name = '" . $q['attachment'] . "'";
                }
@@ -1812,7 +2153,7 @@ class WP_Query {
                if ( intval($q['comments_popup']) )
                        $q['p'] = absint($q['comments_popup']);
 
-               // If an attachment is requested by number, let it supercede any post number.
+               // If an attachment is requested by number, let it supersede any post number.
                if ( $q['attachment_id'] )
                        $q['p'] = absint($q['attachment_id']);
 
@@ -1827,8 +2168,15 @@ class WP_Query {
                        $where .= " AND {$wpdb->posts}.ID NOT IN ($post__not_in)";
                }
 
-               if ( is_numeric($q['post_parent']) )
+               if ( is_numeric( $q['post_parent'] ) ) {
                        $where .= $wpdb->prepare( " AND $wpdb->posts.post_parent = %d ", $q['post_parent'] );
+               } elseif ( $q['post_parent__in'] ) {
+                       $post_parent__in = implode( ',', array_map( 'absint', $q['post_parent__in'] ) );
+                       $where .= " AND {$wpdb->posts}.post_parent IN ($post_parent__in)";
+               } elseif ( $q['post_parent__not_in'] ) {
+                       $post_parent__not_in = implode( ',',  array_map( 'absint', $q['post_parent__not_in'] ) );
+                       $where .= " AND {$wpdb->posts}.post_parent NOT IN ($post_parent__not_in)";
+               }
 
                if ( $q['page_id'] ) {
                        if  ( ('page' != get_option('show_on_front') ) || ( $q['page_id'] != get_option('page_for_posts') ) ) {
@@ -1841,22 +2189,21 @@ class WP_Query {
                if ( !empty($q['s']) ) {
                        // added slashes screw with quote grouping when done early, so done later
                        $q['s'] = stripslashes($q['s']);
+                       if ( empty( $_GET['s'] ) && $this->is_main_query() )
+                               $q['s'] = urldecode($q['s']);
                        if ( !empty($q['sentence']) ) {
                                $q['search_terms'] = array($q['s']);
                        } else {
-                               preg_match_all('/".*?("|$)|((?<=[\\s",+])|^)[^\\s",+]+/', $q['s'], $matches);
+                               preg_match_all('/".*?("|$)|((?<=[\r\n\t ",+])|^)[^\r\n\t ",+]+/', $q['s'], $matches);
                                $q['search_terms'] = array_map('_search_terms_tidy', $matches[0]);
                        }
                        $n = !empty($q['exact']) ? '' : '%';
                        $searchand = '';
                        foreach( (array) $q['search_terms'] as $term ) {
-                               $term = addslashes_gpc($term);
+                               $term = esc_sql( like_escape( $term ) );
                                $search .= "{$searchand}(($wpdb->posts.post_title LIKE '{$n}{$term}{$n}') OR ($wpdb->posts.post_content LIKE '{$n}{$term}{$n}'))";
                                $searchand = ' AND ';
                        }
-                       $term = esc_sql($q['s']);
-                       if ( empty($q['sentence']) && count($q['search_terms']) > 1 && $q['search_terms'][0] != $q['s'] )
-                               $search .= " OR ($wpdb->posts.post_title LIKE '{$n}{$term}{$n}') OR ($wpdb->posts.post_content LIKE '{$n}{$term}{$n}')";
 
                        if ( !empty($search) ) {
                                $search = " AND ({$search}) ";
@@ -1868,205 +2215,89 @@ class WP_Query {
                // Allow plugins to contextually add/remove/modify the search section of the database query
                $search = apply_filters_ref_array('posts_search', array( $search, &$this ) );
 
-               // Category stuff
-
-               if ( empty($q['cat']) || ($q['cat'] == '0') ||
-                               // Bypass cat checks if fetching specific posts
-                               $this->is_singular ) {
-                       $whichcat = '';
-               } else {
-                       $q['cat'] = ''.urldecode($q['cat']).'';
-                       $q['cat'] = addslashes_gpc($q['cat']);
-                       $cat_array = preg_split('/[,\s]+/', $q['cat']);
-                       $q['cat'] = '';
-                       $req_cats = array();
-                       foreach ( (array) $cat_array as $cat ) {
-                               $cat = intval($cat);
-                               $req_cats[] = $cat;
-                               $in = ($cat > 0);
-                               $cat = abs($cat);
-                               if ( $in ) {
-                                       $q['category__in'][] = $cat;
-                                       $q['category__in'] = array_merge($q['category__in'], get_term_children($cat, 'category'));
-                               } else {
-                                       $q['category__not_in'][] = $cat;
-                                       $q['category__not_in'] = array_merge($q['category__not_in'], get_term_children($cat, 'category'));
-                               }
-                       }
-                       $q['cat'] = implode(',', $req_cats);
-               }
-
-               if ( !empty($q['category__in']) ) {
-                       $join = " INNER JOIN $wpdb->term_relationships ON ($wpdb->posts.ID = $wpdb->term_relationships.object_id) INNER JOIN $wpdb->term_taxonomy ON ($wpdb->term_relationships.term_taxonomy_id = $wpdb->term_taxonomy.term_taxonomy_id) ";
-                       $whichcat .= " AND $wpdb->term_taxonomy.taxonomy = 'category' ";
-                       $include_cats = "'" . implode("', '", $q['category__in']) . "'";
-                       $whichcat .= " AND $wpdb->term_taxonomy.term_id IN ($include_cats) ";
-               }
-
-               if ( !empty($q['category__not_in']) ) {
-                       $cat_string = "'" . implode("', '", $q['category__not_in']) . "'";
-                       $whichcat .= " AND $wpdb->posts.ID NOT IN ( SELECT tr.object_id FROM $wpdb->term_relationships AS tr INNER JOIN $wpdb->term_taxonomy AS tt ON tr.term_taxonomy_id = tt.term_taxonomy_id WHERE tt.taxonomy = 'category' AND tt.term_id IN ($cat_string) )";
-               }
-
-               // Category stuff for nice URLs
-               if ( '' != $q['category_name'] && !$this->is_singular ) {
-                       $q['category_name'] = implode('/', array_map('sanitize_title', explode('/', $q['category_name'])));
-                       $reqcat = get_category_by_path($q['category_name']);
-                       $q['category_name'] = str_replace('%2F', '/', urlencode(urldecode($q['category_name'])));
-                       $cat_paths = '/' . trim($q['category_name'], '/');
-                       $q['category_name'] = sanitize_title(basename($cat_paths));
-
-                       $cat_paths = '/' . trim(urldecode($q['category_name']), '/');
-                       $q['category_name'] = sanitize_title(basename($cat_paths));
-                       $cat_paths = explode('/', $cat_paths);
-                       $cat_path = '';
-                       foreach ( (array) $cat_paths as $pathdir )
-                               $cat_path .= ( $pathdir != '' ? '/' : '' ) . sanitize_title($pathdir);
-
-                       //if we don't match the entire hierarchy fallback on just matching the nicename
-                       if ( empty($reqcat) )
-                               $reqcat = get_category_by_path($q['category_name'], false);
-
-                       if ( !empty($reqcat) )
-                               $reqcat = $reqcat->term_id;
-                       else
-                               $reqcat = 0;
+               // Taxonomies
+               if ( !$this->is_singular ) {
+                       $this->parse_tax_query( $q );
 
-                       $q['cat'] = $reqcat;
+                       $clauses = $this->tax_query->get_sql( $wpdb->posts, 'ID' );
 
-                       $join = " INNER JOIN $wpdb->term_relationships ON ($wpdb->posts.ID = $wpdb->term_relationships.object_id) INNER JOIN $wpdb->term_taxonomy ON ($wpdb->term_relationships.term_taxonomy_id = $wpdb->term_taxonomy.term_taxonomy_id) ";
-                       $whichcat = " AND $wpdb->term_taxonomy.taxonomy = 'category' ";
-                       $in_cats = array($q['cat']);
-                       $in_cats = array_merge($in_cats, get_term_children($q['cat'], 'category'));
-                       $in_cats = "'" . implode("', '", $in_cats) . "'";
-                       $whichcat .= "AND $wpdb->term_taxonomy.term_id IN ($in_cats)";
-                       $groupby = "{$wpdb->posts}.ID";
+                       $join .= $clauses['join'];
+                       $where .= $clauses['where'];
                }
 
-               // Tags
-               if ( '' != $q['tag'] ) {
-                       if ( strpos($q['tag'], ',') !== false ) {
-                               $tags = preg_split('/[,\s]+/', $q['tag']);
-                               foreach ( (array) $tags as $tag ) {
-                                       $tag = sanitize_term_field('slug', $tag, 0, 'post_tag', 'db');
-                                       $q['tag_slug__in'][] = $tag;
-                               }
-                       } else if ( preg_match('/[+\s]+/', $q['tag']) || !empty($q['cat']) ) {
-                               $tags = preg_split('/[+\s]+/', $q['tag']);
-                               foreach ( (array) $tags as $tag ) {
-                                       $tag = sanitize_term_field('slug', $tag, 0, 'post_tag', 'db');
-                                       $q['tag_slug__and'][] = $tag;
+               if ( $this->is_tax ) {
+                       if ( empty($post_type) ) {
+                               // Do a fully inclusive search for currently registered post types of queried taxonomies
+                               $post_type = array();
+                               $taxonomies = wp_list_pluck( $this->tax_query->queries, 'taxonomy' );
+                               foreach ( get_post_types( array( 'exclude_from_search' => false ) ) as $pt ) {
+                                       $object_taxonomies = $pt === 'attachment' ? get_taxonomies_for_attachments() : get_object_taxonomies( $pt );
+                                       if ( array_intersect( $taxonomies, $object_taxonomies ) )
+                                               $post_type[] = $pt;
                                }
-                       } else {
-                               $q['tag'] = sanitize_term_field('slug', $q['tag'], 0, 'post_tag', 'db');
-                               $q['tag_slug__in'][] = $q['tag'];
+                               if ( ! $post_type )
+                                       $post_type = 'any';
+                               elseif ( count( $post_type ) == 1 )
+                                       $post_type = $post_type[0];
+
+                               $post_status_join = true;
+                       } elseif ( in_array('attachment', (array) $post_type) ) {
+                               $post_status_join = true;
                        }
                }
 
-               if ( !empty($q['category__in']) || !empty($q['meta_key']) || !empty($q['tag__in']) || !empty($q['tag_slug__in']) ) {
-                       $groupby = "{$wpdb->posts}.ID";
-               }
-
-               if ( !empty($q['tag__in']) && empty($q['cat']) ) {
-                       $join = " INNER JOIN $wpdb->term_relationships ON ($wpdb->posts.ID = $wpdb->term_relationships.object_id) INNER JOIN $wpdb->term_taxonomy ON ($wpdb->term_relationships.term_taxonomy_id = $wpdb->term_taxonomy.term_taxonomy_id) ";
-                       $whichcat .= " AND $wpdb->term_taxonomy.taxonomy = 'post_tag' ";
-                       $include_tags = "'" . implode("', '", $q['tag__in']) . "'";
-                       $whichcat .= " AND $wpdb->term_taxonomy.term_id IN ($include_tags) ";
-                       $reqtag = term_exists( $q['tag__in'][0], 'post_tag' );
-                       if ( !empty($reqtag) )
-                               $q['tag_id'] = $reqtag['term_id'];
-               }
-
-               if ( !empty($q['tag_slug__in']) && empty($q['cat']) ) {
-                       $join = " INNER JOIN $wpdb->term_relationships ON ($wpdb->posts.ID = $wpdb->term_relationships.object_id) INNER JOIN $wpdb->term_taxonomy ON ($wpdb->term_relationships.term_taxonomy_id = $wpdb->term_taxonomy.term_taxonomy_id) INNER JOIN $wpdb->terms ON ($wpdb->term_taxonomy.term_id = $wpdb->terms.term_id) ";
-                       $whichcat .= " AND $wpdb->term_taxonomy.taxonomy = 'post_tag' ";
-                       $include_tags = "'" . implode("', '", $q['tag_slug__in']) . "'";
-                       $whichcat .= " AND $wpdb->terms.slug IN ($include_tags) ";
-                       $reqtag = get_term_by( 'slug', $q['tag_slug__in'][0], 'post_tag' );
-                       if ( !empty($reqtag) )
-                               $q['tag_id'] = $reqtag->term_id;
-               }
-
-               if ( !empty($q['tag__not_in']) ) {
-                       $tag_string = "'" . implode("', '", $q['tag__not_in']) . "'";
-                       $whichcat .= " AND $wpdb->posts.ID NOT IN ( SELECT tr.object_id FROM $wpdb->term_relationships AS tr INNER JOIN $wpdb->term_taxonomy AS tt ON tr.term_taxonomy_id = tt.term_taxonomy_id WHERE tt.taxonomy = 'post_tag' AND tt.term_id IN ($tag_string) )";
-               }
-
-               // Tag and slug intersections.
-               $intersections = array('category__and' => 'category', 'tag__and' => 'post_tag', 'tag_slug__and' => 'post_tag', 'tag__in' => 'post_tag', 'tag_slug__in' => 'post_tag');
-               $tagin = array('tag__in', 'tag_slug__in'); // These are used to make some exceptions below
-               foreach ( $intersections as $item => $taxonomy ) {
-                       if ( empty($q[$item]) ) continue;
-                       if ( in_array($item, $tagin) && empty($q['cat']) ) continue; // We should already have what we need if categories aren't being used
-
-                       if ( $item != 'category__and' ) {
-                               $reqtag = term_exists( $q[$item][0], 'post_tag' );
-                               if ( !empty($reqtag) )
-                                       $q['tag_id'] = $reqtag['term_id'];
-                       }
-
-                       if ( in_array( $item, array('tag_slug__and', 'tag_slug__in' ) ) )
-                               $taxonomy_field = 'slug';
-                       else
-                               $taxonomy_field = 'term_id';
-
-                       $q[$item] = array_unique($q[$item]);
-                       $tsql = "SELECT p.ID FROM $wpdb->posts p INNER JOIN $wpdb->term_relationships tr ON (p.ID = tr.object_id) INNER JOIN $wpdb->term_taxonomy tt ON (tr.term_taxonomy_id = tt.term_taxonomy_id) INNER JOIN $wpdb->terms t ON (tt.term_id = t.term_id)";
-                       $tsql .= " WHERE tt.taxonomy = '$taxonomy' AND t.$taxonomy_field IN ('" . implode("', '", $q[$item]) . "')";
-                       if ( !in_array($item, $tagin) ) { // This next line is only helpful if we are doing an and relationship
-                               $tsql .= " GROUP BY p.ID HAVING count(p.ID) = " . count($q[$item]);
-                       }
-                       $post_ids = $wpdb->get_col($tsql);
+               // Back-compat
+               if ( !empty($this->tax_query->queries) ) {
+                       $tax_query_in_and = wp_list_filter( $this->tax_query->queries, array( 'operator' => 'NOT IN' ), 'NOT' );
+                       if ( !empty( $tax_query_in_and ) ) {
+                               if ( !isset( $q['taxonomy'] ) ) {
+                                       foreach ( $tax_query_in_and as $a_tax_query ) {
+                                               if ( !in_array( $a_tax_query['taxonomy'], array( 'category', 'post_tag' ) ) ) {
+                                                       $q['taxonomy'] = $a_tax_query['taxonomy'];
+                                                       if ( 'slug' == $a_tax_query['field'] )
+                                                               $q['term'] = $a_tax_query['terms'][0];
+                                                       else
+                                                               $q['term_id'] = $a_tax_query['terms'][0];
 
-                       if ( count($post_ids) )
-                               $whichcat .= " AND $wpdb->posts.ID IN (" . implode(', ', $post_ids) . ") ";
-                       else {
-                               $whichcat = " AND 0 = 1";
-                               break;
-                       }
-               }
-
-               // Taxonomies
-               if ( $this->is_tax ) {
-                       if ( '' != $q['taxonomy'] ) {
-                               $taxonomy = $q['taxonomy'];
-                               $tt[$taxonomy] = $q['term'];
-                       } else {
-                               foreach ( $GLOBALS['wp_taxonomies'] as $taxonomy => $t ) {
-                                       if ( $t->query_var && '' != $q[$t->query_var] ) {
-                                               $tt[$taxonomy] = $q[$t->query_var];
-                                               break;
+                                                       break;
+                                               }
                                        }
                                }
-                       }
 
-                       $terms = get_terms($taxonomy, array('slug' => $tt[$taxonomy], 'hide_empty' => !is_taxonomy_hierarchical($taxonomy)));
+                               $cat_query = wp_list_filter( $tax_query_in_and, array( 'taxonomy' => 'category' ) );
+                               if ( ! empty( $cat_query ) ) {
+                                       $cat_query = reset( $cat_query );
 
-                       if ( is_wp_error($terms) || empty($terms) ) {
-                               $whichcat = " AND 0 ";
-                       } else {
-                               foreach ( $terms as $term ) {
-                                       $term_ids[] = $term->term_id;
-                                       if ( is_taxonomy_hierarchical($taxonomy) ) {
-                                               $children = get_term_children($term->term_id, $taxonomy);
-                                               $term_ids = array_merge($term_ids, $children);
+                                       if ( ! empty( $cat_query['terms'][0] ) ) {
+                                               $the_cat = get_term_by( $cat_query['field'], $cat_query['terms'][0], 'category' );
+                                               if ( $the_cat ) {
+                                                       $this->set( 'cat', $the_cat->term_id );
+                                                       $this->set( 'category_name', $the_cat->slug );
+                                               }
+                                               unset( $the_cat );
                                        }
                                }
-                               $post_ids = get_objects_in_term($term_ids, $taxonomy);
-                               if ( !is_wp_error($post_ids) && !empty($post_ids) ) {
-                                       $whichcat .= " AND $wpdb->posts.ID IN (" . implode(', ', $post_ids) . ") ";
-                                       if ( empty($post_type) ) {
-                                               $post_type = 'any';
-                                               $post_status_join = true;
-                                       } elseif ( in_array('attachment', (array)$post_type) ) {
-                                               $post_status_join = true;
+                               unset( $cat_query );
+
+                               $tag_query = wp_list_filter( $tax_query_in_and, array( 'taxonomy' => 'post_tag' ) );
+                               if ( ! empty( $tag_query ) ) {
+                                       $tag_query = reset( $tag_query );
+
+                                       if ( ! empty( $tag_query['terms'][0] ) ) {
+                                               $the_tag = get_term_by( $tag_query['field'], $tag_query['terms'][0], 'post_tag' );
+                                               if ( $the_tag )
+                                                       $this->set( 'tag_id', $the_tag->term_id );
+                                               unset( $the_tag );
                                        }
-                               } else {
-                                       $whichcat = " AND 0 ";
                                }
+                               unset( $tag_query );
                        }
                }
 
+               if ( !empty( $this->tax_query->queries ) || !empty( $this->meta_query->queries ) ) {
+                       $groupby = "{$wpdb->posts}.ID";
+               }
+
                // Author/user stuff
 
                if ( empty($q['author']) || ($q['author'] == '0') ) {
@@ -2099,10 +2330,10 @@ class WP_Query {
                                if ( $q['author_name'][ count($q['author_name'])-1 ] ) {
                                        $q['author_name'] = $q['author_name'][count($q['author_name'])-1]; // no trailing slash
                                } else {
-                                       $q['author_name'] = $q['author_name'][count($q['author_name'])-2]; // there was a trailling slash
+                                       $q['author_name'] = $q['author_name'][count($q['author_name'])-2]; // there was a trailing slash
                                }
                        }
-                       $q['author_name'] = sanitize_title($q['author_name']);
+                       $q['author_name'] = sanitize_title_for_query( $q['author_name'] );
                        $q['author'] = get_user_by('slug', $q['author_name']);
                        if ( $q['author'] )
                                $q['author'] = $q['author']->ID;
@@ -2111,24 +2342,26 @@ class WP_Query {
 
                // MIME-Type stuff for attachment browsing
 
-               if ( isset($q['post_mime_type']) && '' != $q['post_mime_type'] ) {
-                       $table_alias = $post_status_join ? $wpdb->posts : '';
-                       $whichmimetype = wp_post_mime_type_where($q['post_mime_type'], $table_alias);
-               }
+               if ( isset( $q['post_mime_type'] ) && '' != $q['post_mime_type'] )
+                       $whichmimetype = wp_post_mime_type_where( $q['post_mime_type'], $wpdb->posts );
 
-               $where .= $search . $whichcat . $whichauthor . $whichmimetype;
+               $where .= $search . $whichauthor . $whichmimetype;
 
                if ( empty($q['order']) || ((strtoupper($q['order']) != 'ASC') && (strtoupper($q['order']) != 'DESC')) )
                        $q['order'] = 'DESC';
 
                // Order by
                if ( empty($q['orderby']) ) {
-                       $q['orderby'] = "$wpdb->posts.post_date " . $q['order'];
+                       $orderby = "$wpdb->posts.post_date " . $q['order'];
                } elseif ( 'none' == $q['orderby'] ) {
-                       $q['orderby'] = '';
+                       $orderby = '';
+               } elseif ( $q['orderby'] == 'post__in' && ! empty( $post__in ) ) {
+                       $orderby = "FIELD( {$wpdb->posts}.ID, $post__in )";
+               } elseif ( $q['orderby'] == 'post_parent__in' && ! empty( $post_parent__in ) ) {
+                       $orderby = "FIELD( {$wpdb->posts}.post_parent, $post_parent__in )";
                } else {
                        // Used to filter values
-                       $allowed_keys = array('author', 'date', 'title', 'modified', 'menu_order', 'parent', 'ID', 'rand', 'comment_count');
+                       $allowed_keys = array('name', 'author', 'date', 'title', 'modified', 'menu_order', 'parent', 'ID', 'rand', 'comment_count');
                        if ( !empty($q['meta_key']) ) {
                                $allowed_keys[] = $q['meta_key'];
                                $allowed_keys[] = 'meta_value';
@@ -2136,16 +2369,16 @@ class WP_Query {
                        }
                        $q['orderby'] = urldecode($q['orderby']);
                        $q['orderby'] = addslashes_gpc($q['orderby']);
-                       $orderby_array = explode(' ', $q['orderby']);
-                       $q['orderby'] = '';
 
-                       foreach ( $orderby_array as $i => $orderby ) {
+                       $orderby_array = array();
+                       foreach ( explode( ' ', $q['orderby'] ) as $i => $orderby ) {
                                // Only allow certain values for safety
                                if ( ! in_array($orderby, $allowed_keys) )
                                        continue;
 
                                switch ( $orderby ) {
                                        case 'menu_order':
+                                               $orderby = "$wpdb->posts.menu_order";
                                                break;
                                        case 'ID':
                                                $orderby = "$wpdb->posts.ID";
@@ -2167,34 +2400,30 @@ class WP_Query {
                                                $orderby = "$wpdb->posts.post_" . $orderby;
                                }
 
-                               $q['orderby'] .= (($i == 0) ? '' : ',') . $orderby;
+                               $orderby_array[] = $orderby;
                        }
+                       $orderby = implode( ',', $orderby_array );
 
-                       // append ASC or DESC at the end
-                       if ( !empty($q['orderby']))
-                               $q['orderby'] .= " {$q['order']}";
-
-                       if ( empty($q['orderby']) )
-                               $q['orderby'] = "$wpdb->posts.post_date ".$q['order'];
+                       if ( empty( $orderby ) )
+                               $orderby = "$wpdb->posts.post_date ".$q['order'];
+                       else
+                               $orderby .= " {$q['order']}";
                }
 
-               if ( is_array($post_type) ) {
+               if ( is_array( $post_type ) && count( $post_type ) > 1 ) {
                        $post_type_cap = 'multiple_post_type';
                } else {
-                       $post_type_object = get_post_type_object ( $post_type );
-                       if ( !empty($post_type_object) )
-                               $post_type_cap = $post_type_object->capability_type;
-                       else
+                       if ( is_array( $post_type ) )
+                               $post_type = reset( $post_type );
+                       $post_type_object = get_post_type_object( $post_type );
+                       if ( empty( $post_type_object ) )
                                $post_type_cap = $post_type;
                }
 
-               $exclude_post_types = '';
-               $in_search_post_types = get_post_types( array('exclude_from_search' => false) );
-               if ( ! empty( $in_search_post_types ) )
-                       $exclude_post_types .= $wpdb->prepare(" AND $wpdb->posts.post_type IN ('" . join("', '", $in_search_post_types ) . "')");
-
                if ( 'any' == $post_type ) {
-                       $where .= $exclude_post_types;
+                       $in_search_post_types = get_post_types( array('exclude_from_search' => false) );
+                       if ( ! empty( $in_search_post_types ) )
+                               $where .= " AND $wpdb->posts.post_type IN ('" . join("', '", $in_search_post_types ) . "')";
                } elseif ( !empty( $post_type ) && is_array( $post_type ) ) {
                        $where .= " AND $wpdb->posts.post_type IN ('" . join("', '", $post_type) . "')";
                } elseif ( ! empty( $post_type ) ) {
@@ -2211,26 +2440,26 @@ class WP_Query {
                        $post_type_object = get_post_type_object ( 'post' );
                }
 
-               if ( !empty($post_type_object) ) {
-                       $post_type_cap = $post_type_object->capability_type;
-                       $edit_cap = $post_type_object->cap->edit_post;
-                       $read_cap = $post_type_object->cap->read_post;
+               $edit_cap = 'edit_post';
+               $read_cap = 'read_post';
+
+               if ( ! empty( $post_type_object ) ) {
                        $edit_others_cap = $post_type_object->cap->edit_others_posts;
                        $read_private_cap = $post_type_object->cap->read_private_posts;
                } else {
-                       $edit_cap = 'edit_' . $post_type_cap;
-                       $read_cap = 'read_' . $post_type_cap;
                        $edit_others_cap = 'edit_others_' . $post_type_cap . 's';
                        $read_private_cap = 'read_private_' . $post_type_cap . 's';
                }
 
-               if ( isset($q['post_status']) && '' != $q['post_status'] ) {
+               if ( ! empty( $q['post_status'] ) ) {
                        $statuswheres = array();
-                       $q_status = explode(',', $q['post_status']);
+                       $q_status = $q['post_status'];
+                       if ( ! is_array( $q_status ) )
+                               $q_status = explode(',', $q_status);
                        $r_status = array();
                        $p_status = array();
                        $e_status = array();
-                       if ( $q['post_status'] == 'any' ) {
+                       if ( in_array('any', $q_status) ) {
                                foreach ( get_post_stati( array('exclude_from_search' => true) ) as $status )
                                        $e_status[] = "$wpdb->posts.post_status <> '$status'";
                        } else {
@@ -2254,13 +2483,13 @@ class WP_Query {
                        }
                        if ( !empty($r_status) ) {
                                if ( !empty($q['perm'] ) && 'editable' == $q['perm'] && !current_user_can($edit_others_cap) )
-                                       $statuswheres[] = "($wpdb->posts.post_author = $user_ID " .  "AND (" . join( ' OR ', $r_status ) . "))";
+                                       $statuswheres[] = "($wpdb->posts.post_author = $user_ID " . "AND (" . join( ' OR ', $r_status ) . "))";
                                else
                                        $statuswheres[] = "(" . join( ' OR ', $r_status ) . ")";
                        }
                        if ( !empty($p_status) ) {
                                if ( !empty($q['perm'] ) && 'readable' == $q['perm'] && !current_user_can($read_private_cap) )
-                                       $statuswheres[] = "($wpdb->posts.post_author = $user_ID " .  "AND (" . join( ' OR ', $p_status ) . "))";
+                                       $statuswheres[] = "($wpdb->posts.post_author = $user_ID " . "AND (" . join( ' OR ', $p_status ) . "))";
                                else
                                        $statuswheres[] = "(" . join( ' OR ', $p_status ) . ")";
                        }
@@ -2282,7 +2511,7 @@ class WP_Query {
                                $where .= " OR $wpdb->posts.post_status = '$state'";
                        }
 
-                       if ( is_admin() ) {
+                       if ( $this->is_admin ) {
                                // Add protected states that should show in the admin all list.
                                $admin_all_states = get_post_stati( array('protected' => true, 'show_in_admin_all_list' => true) );
                                foreach ( (array) $admin_all_states as $state )
@@ -2299,16 +2528,10 @@ class WP_Query {
                        $where .= ')';
                }
 
-               // postmeta queries
-               if ( ! empty($q['meta_key']) || ! empty($q['meta_value']) )
-                       $join .= " JOIN $wpdb->postmeta ON ($wpdb->posts.ID = $wpdb->postmeta.post_id) ";
-               if ( ! empty($q['meta_key']) )
-                       $where .= $wpdb->prepare(" AND $wpdb->postmeta.meta_key = %s ", $q['meta_key']);
-               if ( ! empty($q['meta_value']) ) {
-                       if ( empty($q['meta_compare']) || ! in_array($q['meta_compare'], array('=', '!=', '>', '>=', '<', '<=')) )
-                               $q['meta_compare'] = '=';
-
-                       $where .= $wpdb->prepare("AND $wpdb->postmeta.meta_value {$q['meta_compare']} %s ", $q['meta_value']);
+               if ( !empty( $this->meta_query->queries ) ) {
+                       $clauses = $this->meta_query->get_sql( 'post', $wpdb->posts, 'ID', $this );
+                       $join .= $clauses['join'];
+                       $where .= $clauses['where'];
                }
 
                // Apply filters on where and join prior to paging so that any
@@ -2321,18 +2544,16 @@ class WP_Query {
                // Paging
                if ( empty($q['nopaging']) && !$this->is_singular ) {
                        $page = absint($q['paged']);
-                       if ( empty($page) )
+                       if ( !$page )
                                $page = 1;
 
                        if ( empty($q['offset']) ) {
-                               $pgstrt = '';
                                $pgstrt = ($page - 1) * $q['posts_per_page'] . ', ';
-                               $limits = 'LIMIT ' . $pgstrt . $q['posts_per_page'];
                        } else { // we're ignoring $page and using 'offset'
                                $q['offset'] = absint($q['offset']);
                                $pgstrt = $q['offset'] . ', ';
-                               $limits = 'LIMIT ' . $pgstrt . $q['posts_per_page'];
                        }
+                       $limits = 'LIMIT ' . $pgstrt . $q['posts_per_page'];
                }
 
                // Comments feeds
@@ -2373,9 +2594,9 @@ class WP_Query {
                                $where = "AND 0";
                }
 
-               $orderby = $q['orderby'];
+               $pieces = array( 'where', 'groupby', 'join', 'orderby', 'distinct', 'fields', 'limits' );
 
-               // Apply post-paging filters on where and join.  Only plugins that
+               // Apply post-paging filters on where and join. Only plugins that
                // manipulate paging queries should use these hooks.
                if ( !$q['suppress_filters'] ) {
                        $where          = apply_filters_ref_array( 'posts_where_paged', array( $where, &$this ) );
@@ -2385,36 +2606,96 @@ class WP_Query {
                        $distinct       = apply_filters_ref_array( 'posts_distinct',    array( $distinct, &$this ) );
                        $limits         = apply_filters_ref_array( 'post_limits',               array( $limits, &$this ) );
                        $fields         = apply_filters_ref_array( 'posts_fields',              array( $fields, &$this ) );
+
+                       // Filter all clauses at once, for convenience
+                       $clauses = (array) apply_filters_ref_array( 'posts_clauses', array( compact( $pieces ), &$this ) );
+                       foreach ( $pieces as $piece )
+                               $$piece = isset( $clauses[ $piece ] ) ? $clauses[ $piece ] : '';
                }
 
-               // Announce current selection parameters.  For use by caching plugins.
+               // Announce current selection parameters. For use by caching plugins.
                do_action( 'posts_selection', $where . $groupby . $orderby . $limits . $join );
 
-               // Filter again for the benefit of caching plugins.  Regular plugins should use the hooks above.
+               // Filter again for the benefit of caching plugins. Regular plugins should use the hooks above.
                if ( !$q['suppress_filters'] ) {
-                       $where          = apply_filters_ref_array( 'posts_where_request',       array( $where, &$this ) );
+                       $where          = apply_filters_ref_array( 'posts_where_request',               array( $where, &$this ) );
                        $groupby        = apply_filters_ref_array( 'posts_groupby_request',             array( $groupby, &$this ) );
-                       $join           = apply_filters_ref_array( 'posts_join_request',        array( $join, &$this ) );
+                       $join           = apply_filters_ref_array( 'posts_join_request',                array( $join, &$this ) );
                        $orderby        = apply_filters_ref_array( 'posts_orderby_request',             array( $orderby, &$this ) );
                        $distinct       = apply_filters_ref_array( 'posts_distinct_request',    array( $distinct, &$this ) );
                        $fields         = apply_filters_ref_array( 'posts_fields_request',              array( $fields, &$this ) );
                        $limits         = apply_filters_ref_array( 'post_limits_request',               array( $limits, &$this ) );
+
+                       // Filter all clauses at once, for convenience
+                       $clauses = (array) apply_filters_ref_array( 'posts_clauses_request', array( compact( $pieces ), &$this ) );
+                       foreach ( $pieces as $piece )
+                               $$piece = isset( $clauses[ $piece ] ) ? $clauses[ $piece ] : '';
                }
 
                if ( ! empty($groupby) )
                        $groupby = 'GROUP BY ' . $groupby;
                if ( !empty( $orderby ) )
                        $orderby = 'ORDER BY ' . $orderby;
+
                $found_rows = '';
                if ( !$q['no_found_rows'] && !empty($limits) )
                        $found_rows = 'SQL_CALC_FOUND_ROWS';
 
-               $this->request = " SELECT $found_rows $distinct $fields FROM $wpdb->posts $join WHERE 1=1 $where $groupby $orderby $limits";
-               if ( !$q['suppress_filters'] )
-                       $this->request = apply_filters_ref_array('posts_request', array( $this->request, &$this ) );
+               $this->request = $old_request = "SELECT $found_rows $distinct $fields FROM $wpdb->posts $join WHERE 1=1 $where $groupby $orderby $limits";
+
+               if ( !$q['suppress_filters'] ) {
+                       $this->request = apply_filters_ref_array( 'posts_request', array( $this->request, &$this ) );
+               }
+
+               if ( 'ids' == $q['fields'] ) {
+                       $this->posts = $wpdb->get_col( $this->request );
+                       $this->post_count = count( $this->posts );
+                       $this->set_found_posts( $q, $limits );
+
+                       return $this->posts;
+               }
+
+               if ( 'id=>parent' == $q['fields'] ) {
+                       $this->posts = $wpdb->get_results( $this->request );
+                       $this->post_count = count( $this->posts );
+                       $this->set_found_posts( $q, $limits );
+
+                       $r = array();
+                       foreach ( $this->posts as $post )
+                               $r[ $post->ID ] = $post->post_parent;
+
+                       return $r;
+               }
+
+               $split_the_query = ( $old_request == $this->request && "$wpdb->posts.*" == $fields && !empty( $limits ) && $q['posts_per_page'] < 500 );
+               $split_the_query = apply_filters( 'split_the_query', $split_the_query, $this );
+
+               if ( $split_the_query ) {
+                       // First get the IDs and then fill in the objects
+
+                       $this->request = "SELECT $found_rows $distinct $wpdb->posts.ID FROM $wpdb->posts $join WHERE 1=1 $where $groupby $orderby $limits";
+
+                       $this->request = apply_filters( 'posts_request_ids', $this->request, $this );
 
-               $this->posts = $wpdb->get_results($this->request);
-               // Raw results filter.  Prior to status checks.
+                       $ids = $wpdb->get_col( $this->request );
+
+                       if ( $ids ) {
+                               $this->posts = $ids;
+                               $this->set_found_posts( $q, $limits );
+                               _prime_post_caches( $ids, $q['update_post_term_cache'], $q['update_post_meta_cache'] );
+                       } else {
+                               $this->posts = array();
+                       }
+               } else {
+                       $this->posts = $wpdb->get_results( $this->request );
+                       $this->set_found_posts( $q, $limits );
+               }
+
+               // Convert to WP_Post objects
+               if ( $this->posts )
+                       $this->posts = array_map( 'get_post', $this->posts );
+
+               // Raw results filter. Prior to status checks.
                if ( !$q['suppress_filters'] )
                        $this->posts = apply_filters_ref_array('posts_results', array( $this->posts, &$this ) );
 
@@ -2431,13 +2712,6 @@ class WP_Query {
                        $this->comment_count = count($this->comments);
                }
 
-               if ( !$q['no_found_rows'] && !empty($limits) ) {
-                       $found_posts_query = apply_filters_ref_array( 'found_posts_query', array( 'SELECT FOUND_ROWS()', &$this ) );
-                       $this->found_posts = $wpdb->get_var( $found_posts_query );
-                       $this->found_posts = apply_filters_ref_array( 'found_posts', array( $this->found_posts, &$this ) );
-                       $this->max_num_pages = ceil($this->found_posts / $q['posts_per_page']);
-               }
-
                // Check post status to determine if post should be displayed.
                if ( !empty($this->posts) && ($this->is_single || $this->is_page) ) {
                        $status = get_post_status($this->posts[0]);
@@ -2466,13 +2740,13 @@ class WP_Query {
                                }
                        }
 
-                       if ( $this->is_preview && current_user_can( $edit_cap, $this->posts[0]->ID ) )
-                               $this->posts[0] = apply_filters_ref_array('the_preview', array( $this->posts[0], &$this ));
+                       if ( $this->is_preview && $this->posts && current_user_can( $edit_cap, $this->posts[0]->ID ) )
+                               $this->posts[0] = get_post( apply_filters_ref_array( 'the_preview', array( $this->posts[0], &$this ) ) );
                }
 
                // Put sticky posts at the top of the posts array
                $sticky_posts = get_option('sticky_posts');
-               if ( $this->is_home && $page <= 1 && is_array($sticky_posts) && !empty($sticky_posts) && !$q['caller_get_posts'] ) {
+               if ( $this->is_home && $page <= 1 && is_array($sticky_posts) && !empty($sticky_posts) && !$q['ignore_sticky_posts'] ) {
                        $num_posts = count($this->posts);
                        $sticky_offset = 0;
                        // Loop over posts and relocate stickies to the front.
@@ -2483,7 +2757,7 @@ class WP_Query {
                                        array_splice($this->posts, $i, 1);
                                        // Move to front, after other stickies
                                        array_splice($this->posts, $sticky_offset, 0, array($sticky_post));
-                                       // Increment the sticky offset.  The next sticky will be placed at this offset.
+                                       // Increment the sticky offset. The next sticky will be placed at this offset.
                                        $sticky_offset++;
                                        // Remove post from sticky posts array
                                        $offset = array_search($sticky_post->ID, $sticky_posts);
@@ -2497,24 +2771,15 @@ class WP_Query {
 
                        // Fetch sticky posts that weren't in the query results
                        if ( !empty($sticky_posts) ) {
-                               $stickies__in = implode(',', array_map( 'absint', $sticky_posts ));
-                               // honor post type(s) if not set to any
-                               $stickies_where = '';
-                               if ( 'any' != $post_type && '' != $post_type ) {
-                                       if ( is_array( $post_type ) ) {
-                                               $post_types = join( "', '", $post_type );
-                                       } else {
-                                               $post_types = $post_type;
-                                       }
-                                       $stickies_where = "AND $wpdb->posts.post_type IN ('" . $post_types . "')";
-                               }
+                               $stickies = get_posts( array(
+                                       'post__in' => $sticky_posts,
+                                       'post_type' => $post_type,
+                                       'post_status' => 'publish',
+                                       'nopaging' => true
+                               ) );
 
-                               $stickies = $wpdb->get_results( "SELECT * FROM $wpdb->posts WHERE $wpdb->posts.ID IN ($stickies__in) $stickies_where" );
                                foreach ( $stickies as $sticky_post ) {
-                                       // Ignore sticky posts the current user cannot read or are not published.
-                                       if ( 'publish' != $sticky_post->post_status )
-                                               continue;
-                                       array_splice($this->posts, $sticky_offset, 0, array($sticky_post));
+                                       array_splice( $this->posts, $sticky_offset, 0, array( $sticky_post ) );
                                        $sticky_offset++;
                                }
                        }
@@ -2523,30 +2788,58 @@ class WP_Query {
                if ( !$q['suppress_filters'] )
                        $this->posts = apply_filters_ref_array('the_posts', array( $this->posts, &$this ) );
 
-               $this->post_count = count($this->posts);
+               // Ensure that any posts added/modified via one of the filters above are
+               // of the type WP_Post and are filtered.
+               if ( $this->posts ) {
+                       $this->post_count = count( $this->posts );
 
-               // Sanitize before caching so it'll only get done once
-               for ( $i = 0; $i < $this->post_count; $i++ ) {
-                       $this->posts[$i] = sanitize_post($this->posts[$i], 'raw');
-               }
+                       $this->posts = array_map( 'get_post', $this->posts );
 
-               if ( $q['cache_results'] )
-                       update_post_caches($this->posts, $post_type, $q['update_post_term_cache'], $q['update_post_meta_cache']);
+                       if ( $q['cache_results'] )
+                               update_post_caches($this->posts, $post_type, $q['update_post_term_cache'], $q['update_post_meta_cache']);
 
-               if ( $this->post_count > 0 ) {
-                       $this->post = $this->posts[0];
+                       $this->post = reset( $this->posts );
+               } else {
+                       $this->post_count = 0;
+                       $this->posts = array();
                }
 
                return $this->posts;
        }
 
+       /**
+        * Set up the amount of found posts and the number of pages (if limit clause was used)
+        * for the current query.
+        *
+        * @since 3.5.0
+        * @access private
+        */
+       function set_found_posts( $q, $limits ) {
+               global $wpdb;
+
+               // Bail if posts is an empty array. Continue if posts is an empty string,
+               // null, or false to accommodate caching plugins that fill posts later.
+               if ( $q['no_found_rows'] || ( is_array( $this->posts ) && ! $this->posts ) )
+                       return;
+
+               if ( ! empty( $limits ) )
+                       $this->found_posts = $wpdb->get_var( apply_filters_ref_array( 'found_posts_query', array( 'SELECT FOUND_ROWS()', &$this ) ) );
+               else
+                       $this->found_posts = count( $this->posts );
+
+               $this->found_posts = apply_filters_ref_array( 'found_posts', array( $this->found_posts, &$this ) );
+
+               if ( ! empty( $limits ) )
+                       $this->max_num_pages = ceil( $this->found_posts / $q['posts_per_page'] );
+       }
+
        /**
         * Set up the next post and iterate current post index.
         *
         * @since 1.5.0
         * @access public
         *
-        * @return object Next post.
+        * @return WP_Post Next post.
         */
        function next_post() {
 
@@ -2690,8 +2983,9 @@ class WP_Query {
         * @param string $query URL query string.
         * @return array List of posts.
         */
-       function &query($query) {
-               $this->parse_query($query);
+       function query( $query ) {
+               $this->init();
+               $this->query = $this->query_vars = wp_parse_args( $query );
                return $this->get_posts();
        }
 
@@ -2711,46 +3005,38 @@ class WP_Query {
                if ( isset($this->queried_object) )
                        return $this->queried_object;
 
-               $this->queried_object = NULL;
+               $this->queried_object = null;
                $this->queried_object_id = 0;
 
-               if ( $this->is_category ) {
-                       $cat = $this->get('cat');
-                       $category = &get_category($cat);
-                       if ( is_wp_error( $category ) )
-                               return NULL;
-                       $this->queried_object = &$category;
-                       $this->queried_object_id = (int) $cat;
-               } elseif ( $this->is_tag ) {
-                       $tag_id = $this->get('tag_id');
-                       $tag = &get_term($tag_id, 'post_tag');
-                       if ( is_wp_error( $tag ) )
-                               return NULL;
-                       $this->queried_object = &$tag;
-                       $this->queried_object_id = (int) $tag_id;
-               } elseif ( $this->is_tax ) {
-                       $tax = $this->get('taxonomy');
-                       $slug = $this->get('term');
-                       $term = &get_terms($tax, array( 'slug' => $slug, 'hide_empty' => false ) );
-                       if ( is_wp_error($term) || empty($term) )
-                               return NULL;
-                       $term = $term[0];
-                       $this->queried_object = $term;
-                       $this->queried_object_id = $term->term_id;
+               if ( $this->is_category || $this->is_tag || $this->is_tax ) {
+                       $tax_query_in_and = wp_list_filter( $this->tax_query->queries, array( 'operator' => 'NOT IN' ), 'NOT' );
+
+                       $query = reset( $tax_query_in_and );
+
+                       if ( 'term_id' == $query['field'] )
+                               $term = get_term( reset( $query['terms'] ), $query['taxonomy'] );
+                       elseif ( $query['terms'] )
+                               $term = get_term_by( $query['field'], reset( $query['terms'] ), $query['taxonomy'] );
+
+                       if ( ! empty( $term ) && ! is_wp_error( $term ) )  {
+                               $this->queried_object = $term;
+                               $this->queried_object_id = (int) $term->term_id;
+
+                               if ( $this->is_category )
+                                       _make_cat_compat( $this->queried_object );
+                       }
+               } elseif ( $this->is_post_type_archive ) {
+                       $this->queried_object = get_post_type_object( $this->get('post_type') );
                } elseif ( $this->is_posts_page ) {
-                       $this->queried_object = & get_page(get_option('page_for_posts'));
+                       $page_for_posts = get_option('page_for_posts');
+                       $this->queried_object = get_post( $page_for_posts );
                        $this->queried_object_id = (int) $this->queried_object->ID;
-               } elseif ( $this->is_single && !is_null($this->post) ) {
-                       $this->queried_object = $this->post;
-                       $this->queried_object_id = (int) $this->post->ID;
-               } elseif ( $this->is_page && !is_null($this->post) ) {
+               } elseif ( $this->is_singular && !is_null($this->post) ) {
                        $this->queried_object = $this->post;
                        $this->queried_object_id = (int) $this->post->ID;
                } elseif ( $this->is_author ) {
-                       $author_id = (int) $this->get('author');
-                       $author = get_userdata($author_id);
-                       $this->queried_object = $author;
-                       $this->queried_object_id = $author_id;
+                       $this->queried_object_id = (int) $this->get('author');
+                       $this->queried_object = get_userdata( $this->queried_object_id );
                }
 
                return $this->queried_object;
@@ -2775,7 +3061,7 @@ class WP_Query {
        }
 
        /**
-        * PHP4 type constructor.
+        * Constructor.
         *
         * Sets up the WordPress query, if parameter is not empty.
         *
@@ -2785,11 +3071,503 @@ class WP_Query {
         * @param string $query URL query string.
         * @return WP_Query
         */
-       function WP_Query($query = '') {
+       function __construct($query = '') {
                if ( ! empty($query) ) {
                        $this->query($query);
                }
        }
+
+       /**
+        * Is the query for an existing archive page?
+        *
+        * Month, Year, Category, Author, Post Type archive...
+        *
+        * @since 3.1.0
+        *
+        * @return bool
+        */
+       function is_archive() {
+               return (bool) $this->is_archive;
+       }
+
+       /**
+        * Is the query for an existing post type archive page?
+        *
+        * @since 3.1.0
+        *
+        * @param mixed $post_types Optional. Post type or array of posts types to check against.
+        * @return bool
+        */
+       function is_post_type_archive( $post_types = '' ) {
+               if ( empty( $post_types ) || !$this->is_post_type_archive )
+                       return (bool) $this->is_post_type_archive;
+
+               $post_type_object = $this->get_queried_object();
+
+               return in_array( $post_type_object->name, (array) $post_types );
+       }
+
+       /**
+        * Is the query for an existing attachment page?
+        *
+        * @since 3.1.0
+        *
+        * @return bool
+        */
+       function is_attachment() {
+               return (bool) $this->is_attachment;
+       }
+
+       /**
+        * Is the query for an existing author archive page?
+        *
+        * If the $author parameter is specified, this function will additionally
+        * check if the query is for one of the authors specified.
+        *
+        * @since 3.1.0
+        *
+        * @param mixed $author Optional. User ID, nickname, nicename, or array of User IDs, nicknames, and nicenames
+        * @return bool
+        */
+       function is_author( $author = '' ) {
+               if ( !$this->is_author )
+                       return false;
+
+               if ( empty($author) )
+                       return true;
+
+               $author_obj = $this->get_queried_object();
+
+               $author = (array) $author;
+
+               if ( in_array( $author_obj->ID, $author ) )
+                       return true;
+               elseif ( in_array( $author_obj->nickname, $author ) )
+                       return true;
+               elseif ( in_array( $author_obj->user_nicename, $author ) )
+                       return true;
+
+               return false;
+       }
+
+       /**
+        * Is the query for an existing category archive page?
+        *
+        * If the $category parameter is specified, this function will additionally
+        * check if the query is for one of the categories specified.
+        *
+        * @since 3.1.0
+        *
+        * @param mixed $category Optional. Category ID, name, slug, or array of Category IDs, names, and slugs.
+        * @return bool
+        */
+       function is_category( $category = '' ) {
+               if ( !$this->is_category )
+                       return false;
+
+               if ( empty($category) )
+                       return true;
+
+               $cat_obj = $this->get_queried_object();
+
+               $category = (array) $category;
+
+               if ( in_array( $cat_obj->term_id, $category ) )
+                       return true;
+               elseif ( in_array( $cat_obj->name, $category ) )
+                       return true;
+               elseif ( in_array( $cat_obj->slug, $category ) )
+                       return true;
+
+               return false;
+       }
+
+       /**
+        * Is the query for an existing tag archive page?
+        *
+        * If the $tag parameter is specified, this function will additionally
+        * check if the query is for one of the tags specified.
+        *
+        * @since 3.1.0
+        *
+        * @param mixed $slug Optional. Tag slug or array of slugs.
+        * @return bool
+        */
+       function is_tag( $slug = '' ) {
+               if ( !$this->is_tag )
+                       return false;
+
+               if ( empty( $slug ) )
+                       return true;
+
+               $tag_obj = $this->get_queried_object();
+
+               $slug = (array) $slug;
+
+               if ( in_array( $tag_obj->slug, $slug ) )
+                       return true;
+
+               return false;
+       }
+
+       /**
+        * Is the query for an existing taxonomy archive page?
+        *
+        * If the $taxonomy parameter is specified, this function will additionally
+        * check if the query is for that specific $taxonomy.
+        *
+        * If the $term parameter is specified in addition to the $taxonomy parameter,
+        * this function will additionally check if the query is for one of the terms
+        * specified.
+        *
+        * @since 3.1.0
+        *
+        * @param mixed $taxonomy Optional. Taxonomy slug or slugs.
+        * @param mixed $term. Optional. Term ID, name, slug or array of Term IDs, names, and slugs.
+        * @return bool
+        */
+       function is_tax( $taxonomy = '', $term = '' ) {
+               global $wp_taxonomies;
+
+               if ( !$this->is_tax )
+                       return false;
+
+               if ( empty( $taxonomy ) )
+                       return true;
+
+               $queried_object = $this->get_queried_object();
+               $tax_array = array_intersect( array_keys( $wp_taxonomies ), (array) $taxonomy );
+               $term_array = (array) $term;
+
+               // Check that the taxonomy matches.
+               if ( ! ( isset( $queried_object->taxonomy ) && count( $tax_array ) && in_array( $queried_object->taxonomy, $tax_array ) ) )
+                       return false;
+
+               // Only a Taxonomy provided.
+               if ( empty( $term ) )
+                       return true;
+
+               return isset( $queried_object->term_id ) &&
+                       count( array_intersect(
+                               array( $queried_object->term_id, $queried_object->name, $queried_object->slug ),
+                               $term_array
+                       ) );
+       }
+
+       /**
+        * Whether the current URL is within the comments popup window.
+        *
+        * @since 3.1.0
+        *
+        * @return bool
+        */
+       function is_comments_popup() {
+               return (bool) $this->is_comments_popup;
+       }
+
+       /**
+        * Is the query for an existing date archive?
+        *
+        * @since 3.1.0
+        *
+        * @return bool
+        */
+       function is_date() {
+               return (bool) $this->is_date;
+       }
+
+       /**
+        * Is the query for an existing day archive?
+        *
+        * @since 3.1.0
+        *
+        * @return bool
+        */
+       function is_day() {
+               return (bool) $this->is_day;
+       }
+
+       /**
+        * Is the query for a feed?
+        *
+        * @since 3.1.0
+        *
+        * @param string|array $feeds Optional feed types to check.
+        * @return bool
+        */
+       function is_feed( $feeds = '' ) {
+               if ( empty( $feeds ) || ! $this->is_feed )
+                       return (bool) $this->is_feed;
+               $qv = $this->get( 'feed' );
+               if ( 'feed' == $qv )
+                       $qv = get_default_feed();
+               return in_array( $qv, (array) $feeds );
+       }
+
+       /**
+        * Is the query for a comments feed?
+        *
+        * @since 3.1.0
+        *
+        * @return bool
+        */
+       function is_comment_feed() {
+               return (bool) $this->is_comment_feed;
+       }
+
+       /**
+        * Is the query for the front page of the site?
+        *
+        * This is for what is displayed at your site's main URL.
+        *
+        * Depends on the site's "Front page displays" Reading Settings 'show_on_front' and 'page_on_front'.
+        *
+        * If you set a static page for the front page of your site, this function will return
+        * true when viewing that page.
+        *
+        * Otherwise the same as @see WP_Query::is_home()
+        *
+        * @since 3.1.0
+        * @uses is_home()
+        * @uses get_option()
+        *
+        * @return bool True, if front of site.
+        */
+       function is_front_page() {
+               // most likely case
+               if ( 'posts' == get_option( 'show_on_front') && $this->is_home() )
+                       return true;
+               elseif ( 'page' == get_option( 'show_on_front') && get_option( 'page_on_front' ) && $this->is_page( get_option( 'page_on_front' ) ) )
+                       return true;
+               else
+                       return false;
+       }
+
+       /**
+        * Is the query for the blog homepage?
+        *
+        * This is the page which shows the time based blog content of your site.
+        *
+        * Depends on the site's "Front page displays" Reading Settings 'show_on_front' and 'page_for_posts'.
+        *
+        * If you set a static page for the front page of your site, this function will return
+        * true only on the page you set as the "Posts page".
+        *
+        * @see WP_Query::is_front_page()
+        *
+        * @since 3.1.0
+        *
+        * @return bool True if blog view homepage.
+        */
+       function is_home() {
+               return (bool) $this->is_home;
+       }
+
+       /**
+        * Is the query for an existing month archive?
+        *
+        * @since 3.1.0
+        *
+        * @return bool
+        */
+       function is_month() {
+               return (bool) $this->is_month;
+       }
+
+       /**
+        * Is the query for an existing single page?
+        *
+        * If the $page parameter is specified, this function will additionally
+        * check if the query is for one of the pages specified.
+        *
+        * @see WP_Query::is_single()
+        * @see WP_Query::is_singular()
+        *
+        * @since 3.1.0
+        *
+        * @param mixed $page Page ID, title, slug, or array of such.
+        * @return bool
+        */
+       function is_page( $page = '' ) {
+               if ( !$this->is_page )
+                       return false;
+
+               if ( empty( $page ) )
+                       return true;
+
+               $page_obj = $this->get_queried_object();
+
+               $page = (array) $page;
+
+               if ( in_array( $page_obj->ID, $page ) )
+                       return true;
+               elseif ( in_array( $page_obj->post_title, $page ) )
+                       return true;
+               else if ( in_array( $page_obj->post_name, $page ) )
+                       return true;
+
+               return false;
+       }
+
+       /**
+        * Is the query for paged result and not for the first page?
+        *
+        * @since 3.1.0
+        *
+        * @return bool
+        */
+       function is_paged() {
+               return (bool) $this->is_paged;
+       }
+
+       /**
+        * Is the query for a post or page preview?
+        *
+        * @since 3.1.0
+        *
+        * @return bool
+        */
+       function is_preview() {
+               return (bool) $this->is_preview;
+       }
+
+       /**
+        * Is the query for the robots file?
+        *
+        * @since 3.1.0
+        *
+        * @return bool
+        */
+       function is_robots() {
+               return (bool) $this->is_robots;
+       }
+
+       /**
+        * Is the query for a search?
+        *
+        * @since 3.1.0
+        *
+        * @return bool
+        */
+       function is_search() {
+               return (bool) $this->is_search;
+       }
+
+       /**
+        * Is the query for an existing single post?
+        *
+        * Works for any post type, except attachments and pages
+        *
+        * If the $post parameter is specified, this function will additionally
+        * check if the query is for one of the Posts specified.
+        *
+        * @see WP_Query::is_page()
+        * @see WP_Query::is_singular()
+        *
+        * @since 3.1.0
+        *
+        * @param mixed $post Post ID, title, slug, or array of such.
+        * @return bool
+        */
+       function is_single( $post = '' ) {
+               if ( !$this->is_single )
+                       return false;
+
+               if ( empty($post) )
+                       return true;
+
+               $post_obj = $this->get_queried_object();
+
+               $post = (array) $post;
+
+               if ( in_array( $post_obj->ID, $post ) )
+                       return true;
+               elseif ( in_array( $post_obj->post_title, $post ) )
+                       return true;
+               elseif ( in_array( $post_obj->post_name, $post ) )
+                       return true;
+
+               return false;
+       }
+
+       /**
+        * Is the query for an existing single post of any post type (post, attachment, page, ... )?
+        *
+        * If the $post_types parameter is specified, this function will additionally
+        * check if the query is for one of the Posts Types specified.
+        *
+        * @see WP_Query::is_page()
+        * @see WP_Query::is_single()
+        *
+        * @since 3.1.0
+        *
+        * @param mixed $post_types Optional. Post Type or array of Post Types
+        * @return bool
+        */
+       function is_singular( $post_types = '' ) {
+               if ( empty( $post_types ) || !$this->is_singular )
+                       return (bool) $this->is_singular;
+
+               $post_obj = $this->get_queried_object();
+
+               return in_array( $post_obj->post_type, (array) $post_types );
+       }
+
+       /**
+        * Is the query for a specific time?
+        *
+        * @since 3.1.0
+        *
+        * @return bool
+        */
+       function is_time() {
+               return (bool) $this->is_time;
+       }
+
+       /**
+        * Is the query for a trackback endpoint call?
+        *
+        * @since 3.1.0
+        *
+        * @return bool
+        */
+       function is_trackback() {
+               return (bool) $this->is_trackback;
+       }
+
+       /**
+        * Is the query for an existing year archive?
+        *
+        * @since 3.1.0
+        *
+        * @return bool
+        */
+       function is_year() {
+               return (bool) $this->is_year;
+       }
+
+       /**
+        * Is the query a 404 (returns no results)?
+        *
+        * @since 3.1.0
+        *
+        * @return bool
+        */
+       function is_404() {
+               return (bool) $this->is_404;
+       }
+
+       /**
+        * Is the query the main query?
+        *
+        * @since 3.3.0
+        *
+        * @return bool
+        */
+       function is_main_query() {
+               global $wp_the_query;
+               return $wp_the_query === $this;
+       }
 }
 
 /**
@@ -2808,20 +3586,38 @@ function wp_old_slug_redirect() {
        if ( is_404() && '' != $wp_query->query_vars['name'] ) :
                global $wpdb;
 
-               $query = "SELECT post_id FROM $wpdb->postmeta, $wpdb->posts WHERE ID = post_id AND meta_key = '_wp_old_slug' AND meta_value='" . $wp_query->query_vars['name'] . "'";
+               // Guess the current post_type based on the query vars.
+               if ( get_query_var('post_type') )
+                       $post_type = get_query_var('post_type');
+               elseif ( !empty($wp_query->query_vars['pagename']) )
+                       $post_type = 'page';
+               else
+                       $post_type = 'post';
+
+               if ( is_array( $post_type ) ) {
+                       if ( count( $post_type ) > 1 )
+                               return;
+                       $post_type = array_shift( $post_type );
+               }
+
+               // Do not attempt redirect for hierarchical post types
+               if ( is_post_type_hierarchical( $post_type ) )
+                       return;
+
+               $query = $wpdb->prepare("SELECT post_id FROM $wpdb->postmeta, $wpdb->posts WHERE ID = post_id AND post_type = %s AND meta_key = '_wp_old_slug' AND meta_value = %s", $post_type, $wp_query->query_vars['name']);
 
                // if year, monthnum, or day have been specified, make our query more precise
                // just in case there are multiple identical _wp_old_slug values
                if ( '' != $wp_query->query_vars['year'] )
-                       $query .= " AND YEAR(post_date) = '{$wp_query->query_vars['year']}'";
+                       $query .= $wpdb->prepare(" AND YEAR(post_date) = %d", $wp_query->query_vars['year']);
                if ( '' != $wp_query->query_vars['monthnum'] )
-                       $query .= " AND MONTH(post_date) = '{$wp_query->query_vars['monthnum']}'";
+                       $query .= $wpdb->prepare(" AND MONTH(post_date) = %d", $wp_query->query_vars['monthnum']);
                if ( '' != $wp_query->query_vars['day'] )
-                       $query .= " AND DAYOFMONTH(post_date) = '{$wp_query->query_vars['day']}'";
+                       $query .= $wpdb->prepare(" AND DAYOFMONTH(post_date) = %d", $wp_query->query_vars['day']);
 
                $id = (int) $wpdb->get_var($query);
 
-               if ( !$id )
+               if ( ! $id )
                        return;
 
                $link = get_permalink($id);
@@ -2829,7 +3625,7 @@ function wp_old_slug_redirect() {
                if ( !$link )
                        return;
 
-               wp_redirect($link, '301'); // Permanent redirect
+               wp_redirect( $link, 301 ); // Permanent redirect
                exit;
        endif;
 }
@@ -2843,38 +3639,41 @@ function wp_old_slug_redirect() {
  * @uses do_action_ref_array() Calls 'the_post'
  * @return bool True when finished.
  */
-function setup_postdata($post) {
-       global $id, $authordata, $day, $currentmonth, $page, $pages, $multipage, $more, $numpages;
+function setup_postdata( $post ) {
+       global $id, $authordata, $currentday, $currentmonth, $page, $pages, $multipage, $more, $numpages;
 
        $id = (int) $post->ID;
 
        $authordata = get_userdata($post->post_author);
 
-       $day = mysql2date('d.m.y', $post->post_date, false);
+       $currentday = mysql2date('d.m.y', $post->post_date, false);
        $currentmonth = mysql2date('m', $post->post_date, false);
        $numpages = 1;
+       $multipage = 0;
        $page = get_query_var('page');
-       if ( !$page )
+       if ( ! $page )
                $page = 1;
        if ( is_single() || is_page() || is_feed() )
                $more = 1;
        $content = $post->post_content;
-       if ( strpos( $content, '<!--nextpage-->' ) ) {
+       if ( false !== strpos( $content, '<!--nextpage-->' ) ) {
                if ( $page > 1 )
                        $more = 1;
-               $multipage = 1;
-               $content = str_replace("\n<!--nextpage-->\n", '<!--nextpage-->', $content);
-               $content = str_replace("\n<!--nextpage-->", '<!--nextpage-->', $content);
-               $content = str_replace("<!--nextpage-->\n", '<!--nextpage-->', $content);
+               $content = str_replace( "\n<!--nextpage-->\n", '<!--nextpage-->', $content );
+               $content = str_replace( "\n<!--nextpage-->", '<!--nextpage-->', $content );
+               $content = str_replace( "<!--nextpage-->\n", '<!--nextpage-->', $content );
+               // Ignore nextpage at the beginning of the content.
+               if ( 0 === strpos( $content, '<!--nextpage-->' ) )
+                       $content = substr( $content, 15 );
                $pages = explode('<!--nextpage-->', $content);
                $numpages = count($pages);
+               if ( $numpages > 1 )
+                       $multipage = 1;
        } else {
                $pages = array( $post->post_content );
-               $multipage = 0;
        }
 
        do_action_ref_array('the_post', array(&$post));
 
        return true;
 }
-?>