Changeset 41361 for trunk/src/wp-includes/widgets/class-wp-widget-text.php

Timestamp:

09/10/2017 06:32:34 AM (8 years ago)

Author:

westonruter

Message:

Widgets: Add shortcode support inside Text widgets.

• Used now in core to facilitate displaying inserted media. See #40854.
• The [embed] shortcode is not supported because there is no post context for caching oEmbed responses. This depends on #34115.
• Add do_shortcode() to the widget_text_content filter in the same way it is added for the_content at priority 11, with shortcode_unautop() called at priority 10 after wpautop().
• For Text widget in legacy mode, manually apply do_shortcode() (and shortcode_unautop() if auto-paragraph checked) if the core-added widget_text_content filter remains, unless a plugin added do_shortcode() to widget_text to prevent applying shortcodes twice.
• Ensure that global $post is null while filters apply in the Text widget so shortcode handlers won't run with unexpected contexts.

Props westonruter, nacin, aaroncampbell.
See #40854, #34115.
Fixes #10457.

File:

• trunk/src/wp-includes/widgets/class-wp-widget-text.php (modified) (4 diffs)

trunk/src/wp-includes/widgets/class-wp-widget-text.php

@@ -184 +184 @@
      * @since 2.8.0
      *
+     * @global WP_Post $post
+     *
      * @param array $args     Display arguments including 'before_title', 'after_title',
      *                        'before_widget', and 'after_widget'.
@@ -189 +191 @@
      */
     public function widget( $args, $instance ) {
+        global $post;
 
         /** This filter is documented in wp-includes/widgets/class-wp-widget-pages.php */
@@ -206 +209 @@
 
         /*
-         * Just-in-time temporarily upgrade Visual Text widget shortcode handling
-         * (with support added by plugin) from the widget_text filter to
-         * widget_text_content:11 to prevent wpautop from corrupting HTML output
-         * added by the shortcode.
+         * Suspend legacy plugin-supplied do_shortcode() for 'widget_text' filter for the visual Text widget to prevent
+         * shortcodes being processed twice. Now do_shortcode() is added to the 'widget_text_content' filter in core itself
+         * and it applies after wpautop() to prevent corrupting HTML output added by the shortcode. When do_shortcode() is
+         * added to 'widget_text_content' then do_shortcode() will be manually called when in legacy mode as well.
          */
         $widget_text_do_shortcode_priority = has_filter( 'widget_text', 'do_shortcode' );
-        $should_upgrade_shortcode_handling = ( $is_visual_text_widget && false !== $widget_text_do_shortcode_priority );
-        if ( $should_upgrade_shortcode_handling ) {
+        $should_suspend_legacy_shortcode_support = ( $is_visual_text_widget && false !== $widget_text_do_shortcode_priority );
+        if ( $should_suspend_legacy_shortcode_support ) {
             remove_filter( 'widget_text', 'do_shortcode', $widget_text_do_shortcode_priority );
-            add_filter( 'widget_text_content', 'do_shortcode', 11 );
+        }
+
+        // Nullify the $post global during widget rendering to prevent shortcodes from running with the unexpected context.
+        $suspended_post = null;
+        if ( isset( $post ) ) {
+            $suspended_post = $post;
+            $post = null;
         }
 
@@ -245 +254 @@
              */
             $text = apply_filters( 'widget_text_content', $text, $instance, $this );
-
-        } elseif ( ! empty( $instance['filter'] ) ) {
-            $text = wpautop( $text ); // Back-compat for instances prior to 4.8.
-        }
-
-        // Undo temporary upgrade of the plugin-supplied shortcode handling.
-        if ( $should_upgrade_shortcode_handling ) {
-            remove_filter( 'widget_text_content', 'do_shortcode', 11 );
+        } else {
+            // Now in legacy mode, add paragraphs and line breaks when checkbox is checked.
+            if ( ! empty( $instance['filter'] ) ) {
+                $text = wpautop( $text );
+            }
+
+            /*
+             * Manually do shortcodes on the content when the core-added filter is present. It is added by default
+             * in core by adding do_shortcode() to the 'widget_text_content' filter to apply after wpautop().
+             * Since the legacy Text widget runs wpautop() after 'widget_text' filters are applied, the widget in
+             * legacy mode here manually applies do_shortcode() on the content unless the default
+             * core filter for 'widget_text_content' has been removed, or if do_shortcode() has already
+             * been applied via a plugin adding do_shortcode() to 'widget_text' filters.
+             */
+            if ( has_filter( 'widget_text_content', 'do_shortcode' ) && ! $widget_text_do_shortcode_priority ) {
+                if ( ! empty( $instance['filter'] ) ) {
+                    $text = shortcode_unautop( $text );
+                }
+                $text = do_shortcode( $text );
+            }
+        }
+
+        // Restore post global.
+        if ( isset( $suspended_post ) ) {
+            $post = $suspended_post;
+        }
+
+        // Undo suspension of legacy plugin-supplied shortcode handling.
+        if ( $should_suspend_legacy_shortcode_support ) {
             add_filter( 'widget_text', 'do_shortcode', $widget_text_do_shortcode_priority );
         }