List Tables: AJAX actions for List Tables do not need to declare `global $wp_list_table`. List tables on admin screens are in global scope, and they contain hooks that don't pass the the list table as context, hence using globals there so that functions can import them. That problem does not exist in the AJAX actions, which are virtually impossible to hook into as is.

See #37699.


git-svn-id: https://develop.svn.wordpress.org/trunk@38455 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/includes/ajax-actions.php

@@ -79,21 +79,19 @@ function wp_ajax_nopriv_heartbeat() {
  * Ajax handler for fetching a list table.
  *
  * @since 3.1.0
- *
- * @global WP_List_Table $wp_list_table
  */
 function wp_ajax_fetch_list() {
-	global $wp_list_table;
-
 	$list_class = $_GET['list_args']['class'];
 	check_ajax_referer( "fetch-list-$list_class", '_ajax_fetch_list_nonce' );
 
 	$wp_list_table = _get_list_table( $list_class, array( 'screen' => $_GET['list_args']['screen']['id'] ) );
-	if ( ! $wp_list_table )
+	if ( ! $wp_list_table ) {
 		wp_die( 0 );
+	}
 
-	if ( ! $wp_list_table->ajax_user_can() )
+	if ( ! $wp_list_table->ajax_user_can() ) {
 		wp_die( -1 );
+	}
 
 	$wp_list_table->ajax_response();
 
@@ -829,12 +827,8 @@ function wp_ajax_add_link_category( $action ) {
  * Ajax handler to add a tag.
  *
  * @since 3.1.0
- *
- * @global WP_List_Table $wp_list_table
  */
 function wp_ajax_add_tag() {
-	global $wp_list_table;
-
 	check_ajax_referer( 'add-tag', '_wpnonce_add-tag' );
 	$taxonomy = !empty($_POST['taxonomy']) ? $_POST['taxonomy'] : 'post_tag';
 	$tax = get_taxonomy($taxonomy);
@@ -933,36 +927,39 @@ function wp_ajax_get_tagcloud() {
  *
  * @since 3.1.0
  *
- * @global WP_List_Table $wp_list_table
  * @global int           $post_id
  *
  * @param string $action Action to perform.
  */
 function wp_ajax_get_comments( $action ) {
-	global $wp_list_table, $post_id;
-	if ( empty( $action ) )
+	global $post_id;
+	if ( empty( $action ) ) {
 		$action = 'get-comments';
-
+	}
 	check_ajax_referer( $action );
 
 	if ( empty( $post_id ) && ! empty( $_REQUEST['p'] ) ) {
 		$id = absint( $_REQUEST['p'] );
-		if ( ! empty( $id ) )
+		if ( ! empty( $id ) ) {
 			$post_id = $id;
+		}
 	}
 
-	if ( empty( $post_id ) )
+	if ( empty( $post_id ) ) {
 		wp_die( -1 );
+	}
 
 	$wp_list_table = _get_list_table( 'WP_Post_Comments_List_Table', array( 'screen' => 'edit-comments' ) );
 
-	if ( ! current_user_can( 'edit_post', $post_id ) )
+	if ( ! current_user_can( 'edit_post', $post_id ) ) {
 		wp_die( -1 );
+	}
 
 	$wp_list_table->prepare_items();
 
-	if ( !$wp_list_table->has_items() )
+	if ( ! $wp_list_table->has_items() ) {
 		wp_die( 1 );
+	}
 
 	$x = new WP_Ajax_Response();
 	ob_start();
@@ -986,12 +983,9 @@ function wp_ajax_get_comments( $action ) {
  *
  * @since 3.1.0
  *
- * @global WP_List_Table $wp_list_table
- *
  * @param string $action Action to perform.
  */
 function wp_ajax_replyto_comment( $action ) {
-	global $wp_list_table;
 	if ( empty( $action ) )
 		$action = 'replyto-comment';
 
@@ -1108,12 +1102,8 @@ function wp_ajax_replyto_comment( $action ) {
  * Ajax handler for editing a comment.
  *
  * @since 3.1.0
- *
- * @global WP_List_Table $wp_list_table
  */
 function wp_ajax_edit_comment() {
-	global $wp_list_table;
-
 	check_ajax_referer( 'replyto-comment', '_ajax_nonce-replyto-comment' );
 
 	$comment_id = (int) $_POST['comment_ID'];
@@ -1327,14 +1317,12 @@ function wp_ajax_add_meta() {
  *
  * @since 3.1.0
  *
- * @global WP_List_Table $wp_list_table
- *
  * @param string $action Action to perform.
  */
 function wp_ajax_add_user( $action ) {
-	global $wp_list_table;
-	if ( empty( $action ) )
+	if ( empty( $action ) ) {
 		$action = 'add-user';
+	}
 
 	check_ajax_referer( $action );
 	if ( ! current_user_can('create_users') )
@@ -1607,11 +1595,9 @@ function wp_ajax_sample_permalink() {
  * Ajax handler for Quick Edit saving a post from a list table.
  *
  * @since 3.1.0
- *
- * @global WP_List_Table $wp_list_table
  */
 function wp_ajax_inline_save() {
-	global $wp_list_table, $mode;
+	global $mode;
 
 	check_ajax_referer( 'inlineeditnonce', '_inline_edit' );
 
@@ -1707,12 +1693,8 @@ function wp_ajax_inline_save() {
  * Ajax handler for quick edit saving for a term.
  *
  * @since 3.1.0
- *
- * @global WP_List_Table $wp_list_table
  */
 function wp_ajax_inline_save_tax() {
-	global $wp_list_table;
-
 	check_ajax_referer( 'taxinlineeditnonce', '_inline_edit' );
 
 	$taxonomy = sanitize_key( $_POST['taxonomy'] );

src/wp-admin/includes/list-table.php

@@ -63,7 +63,7 @@ function _get_list_table( $class, $args = array() ) {
  * @see get_column_headers(), print_column_headers(), get_hidden_columns()
  */
 function register_column_headers($screen, $columns) {
-	$wp_list_table = new _WP_List_Table_Compat($screen, $columns);
+	new _WP_List_Table_Compat( $screen, $columns );
 }
 
 /**