WordPress 4.6.3-scripts

[autoinstalls/wordpress.git] / wp-includes / revision.php

diff --git a/wp-includes/revision.php b/wp-includes/revision.php
index 48523032e7798022e8998c479e433831e04ee548..07a986c00318aab77ae03490d8bcb443af26a34c 100644 (file)
--- a/wp-includes/revision.php
+++ b/wp-includes/revision.php
@@ -9,78 +9,105 @@
 /**
  * Determines which fields of posts are to be saved in revisions.
  *
 /**
  * Determines which fields of posts are to be saved in revisions.
  *

- * Does two things. If passed a post *array*, it will return a post array ready
- * to be inserted into the posts table as a post revision. Otherwise, returns
- * an array whose keys are the post fields to be saved for post revisions.
- *

  * @since 2.6.0
  * @since 2.6.0

+ * @since 4.5.0 A `WP_Post` object can now be passed to the `$post` parameter.
+ * @since 4.5.0 The optional `$autosave` parameter was deprecated and renamed to `$deprecated`.

  * @access private
  *
  * @access private
  *

- * @param array $post Optional a post array to be processed for insertion as a post revision.
- * @param bool $autosave optional Is the revision an autosave?
- * @return array Post array ready to be inserted as a post revision or array of fields that can be versioned.
+ * @staticvar array $fields
+ *
+ * @param array|WP_Post $post       Optional. A post array or a WP_Post object being processed
+ *                                  for insertion as a post revision. Default empty array.
+ * @param bool          $deprecated Not used.
+ * @return array Array of fields that can be versioned.

  */
  */

-function _wp_post_revision_fields( $post = null, $autosave = false ) {
-       static $fields = false;
+function _wp_post_revision_fields( $post = array(), $deprecated = false ) {
+       static $fields = null;

 
 

-       if ( !$fields ) {
+       if ( ! is_array( $post ) ) {
+               $post = get_post( $post, ARRAY_A );
+       }
+
+       if ( is_null( $fields ) ) {

                // Allow these to be versioned
                $fields = array(
                        'post_title' => __( 'Title' ),
                        'post_content' => __( 'Content' ),
                        'post_excerpt' => __( 'Excerpt' ),
                );
                // Allow these to be versioned
                $fields = array(
                        'post_title' => __( 'Title' ),
                        'post_content' => __( 'Content' ),
                        'post_excerpt' => __( 'Excerpt' ),
                );

+       }

 
 

-               /**
-                * Filter the list of fields saved in post revisions.
-                *
-                * Included by default: 'post_title', 'post_content' and 'post_excerpt'.
-                *
-                * Disallowed fields: 'ID', 'post_name', 'post_parent', 'post_date',
-                * 'post_date_gmt', 'post_status', 'post_type', 'comment_count',
-                * and 'post_author'.
-                *
-                * @since 2.6.0
-                *
-                * @param array $fields List of fields to revision. Contains 'post_title',
-                *                      'post_content', and 'post_excerpt' by default.
-                */
-               $fields = apply_filters( '_wp_post_revision_fields', $fields );
+       /**
+        * Filters the list of fields saved in post revisions.
+        *
+        * Included by default: 'post_title', 'post_content' and 'post_excerpt'.
+        *
+        * Disallowed fields: 'ID', 'post_name', 'post_parent', 'post_date',
+        * 'post_date_gmt', 'post_status', 'post_type', 'comment_count',
+        * and 'post_author'.
+        *
+        * @since 2.6.0
+        * @since 4.5.0 The `$post` parameter was added.
+        *
+        * @param array $fields List of fields to revision. Contains 'post_title',
+        *                      'post_content', and 'post_excerpt' by default.
+        * @param array $post   A post array being processed for insertion as a post revision.
+        */
+       $fields = apply_filters( '_wp_post_revision_fields', $fields, $post );

 
 

-               // WP uses these internally either in versioning or elsewhere - they cannot be versioned
-               foreach ( array( 'ID', 'post_name', 'post_parent', 'post_date', 'post_date_gmt', 'post_status', 'post_type', 'comment_count', 'post_author' ) as $protect )
-                       unset( $fields[$protect] );
+       // WP uses these internally either in versioning or elsewhere - they cannot be versioned
+       foreach ( array( 'ID', 'post_name', 'post_parent', 'post_date', 'post_date_gmt', 'post_status', 'post_type', 'comment_count', 'post_author' ) as $protect ) {
+               unset( $fields[ $protect ] );

        }
 
        }
 

-       if ( !is_array($post) )
-               return $fields;

 
 

-       $return = array();
-       foreach ( array_intersect( array_keys( $post ), array_keys( $fields ) ) as $field )
-               $return[$field] = $post[$field];
+       return $fields;
+}

 
 

-       $return['post_parent']   = $post['ID'];
-       $return['post_status']   = 'inherit';
-       $return['post_type']     = 'revision';
-       $return['post_name']     = $autosave ? "$post[ID]-autosave-v1" : "$post[ID]-revision-v1"; // "1" is the revisioning system version
-       $return['post_date']     = isset($post['post_modified']) ? $post['post_modified'] : '';
-       $return['post_date_gmt'] = isset($post['post_modified_gmt']) ? $post['post_modified_gmt'] : '';
+/**
+ * Returns a post array ready to be inserted into the posts table as a post revision.
+ *
+ * @since 4.5.0
+ * @access private
+ *
+ * @param array|WP_Post $post     Optional. A post array or a WP_Post object to be processed
+ *                                for insertion as a post revision. Default empty array.
+ * @param bool          $autosave Optional. Is the revision an autosave? Default false.
+ * @return array Post array ready to be inserted as a post revision.
+ */
+function _wp_post_revision_data( $post = array(), $autosave = false ) {
+       if ( ! is_array( $post ) ) {
+               $post = get_post( $post, ARRAY_A );
+       }

 
 

-       return $return;
+       $fields = _wp_post_revision_fields( $post );
+
+       $revision_data = array();
+
+       foreach ( array_intersect( array_keys( $post ), array_keys( $fields ) ) as $field ) {
+               $revision_data[ $field ] = $post[ $field ];
+       }
+
+       $revision_data['post_parent']   = $post['ID'];
+       $revision_data['post_status']   = 'inherit';
+       $revision_data['post_type']     = 'revision';
+       $revision_data['post_name']     = $autosave ? "$post[ID]-autosave-v1" : "$post[ID]-revision-v1"; // "1" is the revisioning system version
+       $revision_data['post_date']     = isset( $post['post_modified'] ) ? $post['post_modified'] : '';
+       $revision_data['post_date_gmt'] = isset( $post['post_modified_gmt'] ) ? $post['post_modified_gmt'] : '';
+
+       return $revision_data;

 }
 
 /**
 }
 
 /**

- * Saves an already existing post as a post revision.
+ * Creates a revision for the current version of a post.

  *
  *

- * Typically used immediately after post updates.
- * Adds a copy of the current post as a revision, so latest revision always matches current post
+ * Typically used immediately after a post update, as every update is a revision,
+ * and the most recent revision always matches the current post.

  *
  * @since 2.6.0
  *
  *
  * @since 2.6.0
  *

- * @uses _wp_put_post_revision()
- *

  * @param int $post_id The ID of the post to save as a revision.
  * @param int $post_id The ID of the post to save as a revision.

- * @return mixed Null or 0 if error, new revision ID, if success.
+ * @return int|WP_Error|void Void or 0 if error, new revision ID, if success.

  */
 function wp_save_post_revision( $post_id ) {
        if ( defined( 'DOING_AUTOSAVE' ) && DOING_AUTOSAVE )
  */
 function wp_save_post_revision( $post_id ) {
        if ( defined( 'DOING_AUTOSAVE' ) && DOING_AUTOSAVE )


@@ -111,42 +138,60 @@ function wp_save_post_revision( $post_id ) {
                }
 
                /**
                }
 
                /**

-                * Filter whether the post has changed since the last revision.
+                * Filters whether the post has changed since the last revision.

                 *
                 * By default a revision is saved only if one of the revisioned fields has changed.
                 * This filter can override that so a revision is saved even if nothing has changed.
                 *
                 * @since 3.6.0
                 *
                 *
                 * By default a revision is saved only if one of the revisioned fields has changed.
                 * This filter can override that so a revision is saved even if nothing has changed.
                 *
                 * @since 3.6.0
                 *

-                * @param bool $check_for_changes Whether to check for changes before saving a new revision.
-                *                                Default true.
-                * @param int  $last_revision     ID of the last revision.
-                * @param int  $post              Post ID.
+                * @param bool    $check_for_changes Whether to check for changes before saving a new revision.
+                *                                   Default true.
+                * @param WP_Post $last_revision     The last revision post object.
+                * @param WP_Post $post              The post object.

                 *
                 */
                if ( isset( $last_revision ) && apply_filters( 'wp_save_post_revision_check_for_changes', $check_for_changes = true, $last_revision, $post ) ) {
                        $post_has_changed = false;
 
                 *
                 */
                if ( isset( $last_revision ) && apply_filters( 'wp_save_post_revision_check_for_changes', $check_for_changes = true, $last_revision, $post ) ) {
                        $post_has_changed = false;
 

-                       foreach ( array_keys( _wp_post_revision_fields() ) as $field ) {
+                       foreach ( array_keys( _wp_post_revision_fields( $post ) ) as $field ) {

                                if ( normalize_whitespace( $post->$field ) != normalize_whitespace( $last_revision->$field ) ) {
                                        $post_has_changed = true;
                                        break;
                                }
                        }
                                if ( normalize_whitespace( $post->$field ) != normalize_whitespace( $last_revision->$field ) ) {
                                        $post_has_changed = true;
                                        break;
                                }
                        }

+
+                       /**
+                        * Filters whether a post has changed.
+                        *
+                        * By default a revision is saved only if one of the revisioned fields has changed.
+                        * This filter allows for additional checks to determine if there were changes.
+                        *
+                        * @since 4.1.0
+                        *
+                        * @param bool    $post_has_changed Whether the post has changed.
+                        * @param WP_Post $last_revision    The last revision post object.
+                        * @param WP_Post $post             The post object.
+                        *
+                        */
+                       $post_has_changed = (bool) apply_filters( 'wp_save_post_revision_post_has_changed', $post_has_changed, $last_revision, $post );
+

                        //don't save revision if post unchanged
                        //don't save revision if post unchanged

-                       if( ! $post_has_changed )
+                       if ( ! $post_has_changed ) {

                                return;
                                return;

+                       }

                }
        }
 
        $return = _wp_put_post_revision( $post );
 
                }
        }
 
        $return = _wp_put_post_revision( $post );
 

+       // If a limit for the number of revisions to keep has been set,
+       // delete the oldest ones.

        $revisions_to_keep = wp_revisions_to_keep( $post );
 
        if ( $revisions_to_keep < 0 )
                return $return;
 
        $revisions_to_keep = wp_revisions_to_keep( $post );
 
        if ( $revisions_to_keep < 0 )
                return $return;
 

-       // all revisions and autosaves

        $revisions = wp_get_post_revisions( $post_id, array( 'order' => 'ASC' ) );
 
        $delete = count($revisions) - $revisions_to_keep;
        $revisions = wp_get_post_revisions( $post_id, array( 'order' => 'ASC' ) );
 
        $delete = count($revisions) - $revisions_to_keep;


@@ -175,11 +220,9 @@ function wp_save_post_revision( $post_id ) {
  *
  * @since 2.6.0
  *
  *
  * @since 2.6.0
  *

- * @uses wp_get_post_revisions()
- *

  * @param int $post_id The post ID.
  * @param int $post_id The post ID.

- * @param int $user_id optional The post author ID.
- * @return object|bool The autosaved data or false on failure or when no autosave exists.
+ * @param int $user_id Optional The post author ID.
+ * @return WP_Post|false The autosaved data or false on failure or when no autosave exists.

  */
 function wp_get_post_autosave( $post_id, $user_id = 0 ) {
        $revisions = wp_get_post_revisions( $post_id, array( 'check_enabled' => false ) );
  */
 function wp_get_post_autosave( $post_id, $user_id = 0 ) {
        $revisions = wp_get_post_revisions( $post_id, array( 'check_enabled' => false ) );


@@ -190,7 +233,6 @@ function wp_get_post_autosave( $post_id, $user_id = 0 ) {
                                continue;
 
                        return $revision;
                                continue;
 
                        return $revision;

-                       break;

                }
        }
 
                }
        }
 


@@ -202,8 +244,8 @@ function wp_get_post_autosave( $post_id, $user_id = 0 ) {
  *
  * @since 2.6.0
  *
  *
  * @since 2.6.0
  *

- * @param int|object $post Post ID or post object.
- * @return bool|int False if not a revision, ID of revision's parent otherwise.
+ * @param int|WP_Post $post Post ID or post object.
+ * @return false|int False if not a revision, ID of revision's parent otherwise.

  */
 function wp_is_post_revision( $post ) {
        if ( !$post = wp_get_post_revision( $post ) )
  */
 function wp_is_post_revision( $post ) {
        if ( !$post = wp_get_post_revision( $post ) )


@@ -217,8 +259,8 @@ function wp_is_post_revision( $post ) {
  *
  * @since 2.6.0
  *
  *
  * @since 2.6.0
  *

- * @param int|object $post Post ID or post object.
- * @return bool|int False if not a revision, ID of autosave's parent otherwise
+ * @param int|WP_Post $post Post ID or post object.
+ * @return false|int False if not a revision, ID of autosave's parent otherwise

  */
 function wp_is_post_autosave( $post ) {
        if ( !$post = wp_get_post_revision( $post ) )
  */
 function wp_is_post_autosave( $post ) {
        if ( !$post = wp_get_post_revision( $post ) )


@@ -236,11 +278,9 @@ function wp_is_post_autosave( $post ) {
  * @since 2.6.0
  * @access private
  *
  * @since 2.6.0
  * @access private
  *

- * @uses wp_insert_post()
- *
- * @param int|object|array $post Post ID, post object OR post array.
- * @param bool $autosave Optional. Is the revision an autosave?
- * @return mixed WP_Error or 0 if error, new revision ID if success.
+ * @param int|WP_Post|array|null $post     Post ID, post object OR post array.
+ * @param bool                   $autosave Optional. Is the revision an autosave?
+ * @return int|WP_Error WP_Error or 0 if error, new revision ID if success.

  */
 function _wp_put_post_revision( $post = null, $autosave = false ) {
        if ( is_object($post) )
  */
 function _wp_put_post_revision( $post = null, $autosave = false ) {
        if ( is_object($post) )


@@ -249,13 +289,12 @@ function _wp_put_post_revision( $post = null, $autosave = false ) {
                $post = get_post($post, ARRAY_A);
 
        if ( ! $post || empty($post['ID']) )
                $post = get_post($post, ARRAY_A);
 
        if ( ! $post || empty($post['ID']) )

-               return new WP_Error( 'invalid_post', __( 'Invalid post ID' ) );
+               return new WP_Error( 'invalid_post', __( 'Invalid post ID.' ) );

 
        if ( isset($post['post_type']) && 'revision' == $post['post_type'] )
                return new WP_Error( 'post_type', __( 'Cannot create a revision of a revision' ) );
 
 
        if ( isset($post['post_type']) && 'revision' == $post['post_type'] )
                return new WP_Error( 'post_type', __( 'Cannot create a revision of a revision' ) );
 

-       $post_id = $post['ID'];
-       $post = _wp_post_revision_fields( $post, $autosave );
+       $post = _wp_post_revision_data( $post, $autosave );

        $post = wp_slash($post); //since data is from db
 
        $revision_id = wp_insert_post( $post );
        $post = wp_slash($post); //since data is from db
 
        $revision_id = wp_insert_post( $post );


@@ -281,12 +320,10 @@ function _wp_put_post_revision( $post = null, $autosave = false ) {
  *
  * @since 2.6.0
  *
  *
  * @since 2.6.0
  *

- * @uses get_post()
- *
- * @param int|object $post The post ID or object.
- * @param string $output Optional. OBJECT, ARRAY_A, or ARRAY_N.
- * @param string $filter Optional sanitation filter. @see sanitize_post().
- * @return mixed Null if error or post object if success.
+ * @param int|WP_Post $post   The post ID or object.
+ * @param string      $output Optional. OBJECT, ARRAY_A, or ARRAY_N.
+ * @param string      $filter Optional sanitation filter. See sanitize_post().
+ * @return WP_Post|array|null Null if error or post object if success.

  */
 function wp_get_post_revision(&$post, $output = OBJECT, $filter = 'raw') {
        if ( !$revision = get_post( $post, OBJECT, $filter ) )
  */
 function wp_get_post_revision(&$post, $output = OBJECT, $filter = 'raw') {
        if ( !$revision = get_post( $post, OBJECT, $filter ) )


@@ -314,22 +351,19 @@ function wp_get_post_revision(&$post, $output = OBJECT, $filter = 'raw') {
  *
  * @since 2.6.0
  *
  *
  * @since 2.6.0
  *

- * @uses wp_get_post_revision()
- * @uses wp_update_post()
- *
- * @param int|object $revision_id Revision ID or revision object.
- * @param array $fields Optional. What fields to restore from. Defaults to all.
- * @return mixed Null if error, false if no fields to restore, (int) post ID if success.
+ * @param int|WP_Post $revision_id Revision ID or revision object.
+ * @param array       $fields      Optional. What fields to restore from. Defaults to all.
+ * @return int|false|null Null if error, false if no fields to restore, (int) post ID if success.

  */
 function wp_restore_post_revision( $revision_id, $fields = null ) {
        if ( !$revision = wp_get_post_revision( $revision_id, ARRAY_A ) )
                return $revision;
 
        if ( !is_array( $fields ) )
  */
 function wp_restore_post_revision( $revision_id, $fields = null ) {
        if ( !$revision = wp_get_post_revision( $revision_id, ARRAY_A ) )
                return $revision;
 
        if ( !is_array( $fields ) )

-               $fields = array_keys( _wp_post_revision_fields() );
+               $fields = array_keys( _wp_post_revision_fields( $revision ) );

 
        $update = array();
 
        $update = array();

-       foreach( array_intersect( array_keys( $revision ), $fields ) as $field ) {
+       foreach ( array_intersect( array_keys( $revision ), $fields ) as $field ) {

                $update[$field] = $revision[$field];
        }
 
                $update[$field] = $revision[$field];
        }
 


@@ -344,14 +378,6 @@ function wp_restore_post_revision( $revision_id, $fields = null ) {
        if ( ! $post_id || is_wp_error( $post_id ) )
                return $post_id;
 
        if ( ! $post_id || is_wp_error( $post_id ) )
                return $post_id;
 

-       // Add restore from details
-       $restore_details = array(
-               'restored_revision_id' => $revision_id,
-               'restored_by_user'     => get_current_user_id(),
-               'restored_time'        => time()
-       );
-       update_post_meta( $post_id, '_post_restored_from', $restore_details );
-

        // Update last edit user
        update_post_meta( $post_id, '_edit_last', get_current_user_id() );
 
        // Update last edit user
        update_post_meta( $post_id, '_edit_last', get_current_user_id() );
 


@@ -375,20 +401,15 @@ function wp_restore_post_revision( $revision_id, $fields = null ) {
  *
  * @since 2.6.0
  *
  *
  * @since 2.6.0
  *

- * @uses wp_get_post_revision()
- * @uses wp_delete_post()
- *
- * @param int|object $revision_id Revision ID or revision object.
- * @return mixed Null or WP_Error if error, deleted post if success.
+ * @param int|WP_Post $revision_id Revision ID or revision object.
+ * @return array|false|WP_Post|WP_Error|null Null or WP_Error if error, deleted post if success.

  */
 function wp_delete_post_revision( $revision_id ) {
  */
 function wp_delete_post_revision( $revision_id ) {

-       if ( !$revision = wp_get_post_revision( $revision_id ) )
+       if ( ! $revision = wp_get_post_revision( $revision_id ) ) {

                return $revision;
                return $revision;

+       }

 
        $delete = wp_delete_post( $revision->ID );
 
        $delete = wp_delete_post( $revision->ID );

-       if ( is_wp_error( $delete ) )
-               return $delete;
-

        if ( $delete ) {
                /**
                 * Fires once a post revision has been deleted.
        if ( $delete ) {
                /**
                 * Fires once a post revision has been deleted.


@@ -409,9 +430,10 @@ function wp_delete_post_revision( $revision_id ) {
  *
  * @since 2.6.0
  *
  *
  * @since 2.6.0
  *

- * @uses get_children()
+ * @see get_children()

  *
  *

- * @param int|object $post_id Post ID or post object
+ * @param int|WP_Post $post_id Optional. Post ID or WP_Post object. Default is global `$post`.
+ * @param array|null  $args    Optional. Arguments for retrieving post revisions. Default null.

  * @return array An array of revisions, or an empty array if none.
  */
 function wp_get_post_revisions( $post_id = 0, $args = null ) {
  * @return array An array of revisions, or an empty array if none.
  */
 function wp_get_post_revisions( $post_id = 0, $args = null ) {


@@ -419,7 +441,7 @@ function wp_get_post_revisions( $post_id = 0, $args = null ) {
        if ( ! $post || empty( $post->ID ) )
                return array();
 
        if ( ! $post || empty( $post->ID ) )
                return array();
 

-       $defaults = array( 'order' => 'DESC', 'orderby' => 'date', 'check_enabled' => true );
+       $defaults = array( 'order' => 'DESC', 'orderby' => 'date ID', 'check_enabled' => true );

        $args = wp_parse_args( $args, $defaults );
 
        if ( $args['check_enabled'] && ! wp_revisions_enabled( $post ) )
        $args = wp_parse_args( $args, $defaults );
 
        if ( $args['check_enabled'] && ! wp_revisions_enabled( $post ) )


@@ -438,24 +460,24 @@ function wp_get_post_revisions( $post_id = 0, $args = null ) {
  *
  * @since 3.6.0
  *
  *
  * @since 3.6.0
  *

- * @uses wp_revisions_to_keep()
- *
- * @param object $post The post object.
+ * @param WP_Post $post The post object.

  * @return bool True if number of revisions to keep isn't zero, false otherwise.
  */
 function wp_revisions_enabled( $post ) {
  * @return bool True if number of revisions to keep isn't zero, false otherwise.
  */
 function wp_revisions_enabled( $post ) {

-       return wp_revisions_to_keep( $post ) != 0;
+       return wp_revisions_to_keep( $post ) !== 0;

 }
 
 /**
  * Determine how many revisions to retain for a given post.
 }
 
 /**
  * Determine how many revisions to retain for a given post.

- * By default, an infinite number of revisions are stored if a post type supports revisions.

  *
  *

- * @since 3.6.0
+ * By default, an infinite number of revisions are kept.

  *
  *

- * @uses post_type_supports()
+ * The constant WP_POST_REVISIONS can be set in wp-config to specify the limit
+ * of revisions to keep.

  *
  *

- * @param object $post The post object.
+ * @since 3.6.0
+ *
+ * @param WP_Post $post The post object.

  * @return int The number of revisions to keep.
  */
 function wp_revisions_to_keep( $post ) {
  * @return int The number of revisions to keep.
  */
 function wp_revisions_to_keep( $post ) {


@@ -470,7 +492,7 @@ function wp_revisions_to_keep( $post ) {
                $num = 0;
 
        /**
                $num = 0;
 
        /**

-        * Filter the number of revisions to save for the given post.
+        * Filters the number of revisions to save for the given post.

         *
         * Overrides the value of WP_POST_REVISIONS.
         *
         *
         * Overrides the value of WP_POST_REVISIONS.
         *


@@ -487,24 +509,28 @@ function wp_revisions_to_keep( $post ) {
  *
  * @since 2.7.0
  * @access private
  *
  * @since 2.7.0
  * @access private

+ *
+ * @param WP_Post $post
+ * @return WP_Post|false

  */
  */

-function _set_preview($post) {
-
-       if ( ! is_object($post) )
+function _set_preview( $post ) {
+       if ( ! is_object( $post ) ) {

                return $post;
                return $post;

+       }

 
 

-       $preview = wp_get_post_autosave($post->ID);
-
-       if ( ! is_object($preview) )
+       $preview = wp_get_post_autosave( $post->ID );
+       if ( ! is_object( $preview ) ) {

                return $post;
                return $post;

+       }

 
 

-       $preview = sanitize_post($preview);
+       $preview = sanitize_post( $preview );

 
        $post->post_content = $preview->post_content;
        $post->post_title = $preview->post_title;
        $post->post_excerpt = $preview->post_excerpt;
 
        add_filter( 'get_the_terms', '_wp_preview_terms_filter', 10, 3 );
 
        $post->post_content = $preview->post_content;
        $post->post_title = $preview->post_title;
        $post->post_excerpt = $preview->post_excerpt;
 
        add_filter( 'get_the_terms', '_wp_preview_terms_filter', 10, 3 );

+       add_filter( 'get_post_metadata', '_wp_preview_post_thumbnail_filter', 10, 3 );

 
        return $post;
 }
 
        return $post;
 }


@@ -516,12 +542,11 @@ function _set_preview($post) {
  * @access private
  */
 function _show_post_preview() {
  * @access private
  */
 function _show_post_preview() {

-

        if ( isset($_GET['preview_id']) && isset($_GET['preview_nonce']) ) {
                $id = (int) $_GET['preview_id'];
 
        if ( isset($_GET['preview_id']) && isset($_GET['preview_nonce']) ) {
                $id = (int) $_GET['preview_id'];
 

-               if ( false == wp_verify_nonce( $_GET['preview_nonce'], 'post_preview_' . $id ) )
-                       wp_die( __('You do not have permission to preview drafts.') );
+               if ( false === wp_verify_nonce( $_GET['preview_nonce'], 'post_preview_' . $id ) )
+                       wp_die( __('Sorry, you are not allowed to preview drafts.') );

 
                add_filter('the_preview', '_set_preview');
        }
 
                add_filter('the_preview', '_set_preview');
        }


@@ -532,6 +557,11 @@ function _show_post_preview() {
  *
  * @since 3.6.0
  * @access private
  *
  * @since 3.6.0
  * @access private

+ *
+ * @param array  $terms
+ * @param int    $post_id
+ * @param string $taxonomy
+ * @return array

  */
 function _wp_preview_terms_filter( $terms, $post_id, $taxonomy ) {
        if ( ! $post = get_post() )
  */
 function _wp_preview_terms_filter( $terms, $post_id, $taxonomy ) {
        if ( ! $post = get_post() )


@@ -548,12 +578,49 @@ function _wp_preview_terms_filter( $terms, $post_id, $taxonomy ) {
        return $terms;
 }
 
        return $terms;
 }
 

+/**
+ * Filters post thumbnail lookup to set the post thumbnail.
+ *
+ * @since 4.6.0
+ * @access private
+ *
+ * @param null|array|string $value    The value to return - a single metadata value, or an array of values.
+ * @param int               $post_id  Post ID.
+ * @param string            $meta_key Meta key.
+ * @return null|array The default return value or the post thumbnail meta array.
+ */
+function _wp_preview_post_thumbnail_filter( $value, $post_id, $meta_key ) {
+       if ( ! $post = get_post() ) {
+               return $value;
+       }
+
+       if ( empty( $_REQUEST['_thumbnail_id'] ) ||
+            empty( $_REQUEST['preview_id'] ) ||
+            $post->ID != $post_id ||
+            '_thumbnail_id' != $meta_key ||
+            'revision' == $post->post_type ||
+            $post_id != $_REQUEST['preview_id']
+       ) {
+               return $value;
+       }
+
+       $thumbnail_id = intval( $_REQUEST['_thumbnail_id'] );
+       if ( $thumbnail_id <= 0 ) {
+               return '';
+       }
+
+       return strval( $thumbnail_id );
+}
+

 /**
  * Gets the post revision version.
  *
  * @since 3.6.0
  * @access private
 /**
  * Gets the post revision version.
  *
  * @since 3.6.0
  * @access private

-*/
+ *
+ * @param WP_Post $revision
+ * @return int|false
+ */

 function _wp_get_post_revision_version( $revision ) {
        if ( is_object( $revision ) )
                $revision = get_object_vars( $revision );
 function _wp_get_post_revision_version( $revision ) {
        if ( is_object( $revision ) )
                $revision = get_object_vars( $revision );


@@ -572,10 +639,10 @@ function _wp_get_post_revision_version( $revision ) {
  * @since 3.6.0
  * @access private
  *
  * @since 3.6.0
  * @access private
  *

- * @uses wp_get_post_revisions()
+ * @global wpdb $wpdb WordPress database abstraction object.

  *
  *

- * @param object $post Post object
- * @param array $revisions Current revisions of the post
+ * @param WP_Post $post      Post object
+ * @param array   $revisions Current revisions of the post

  * @return bool true if the revisions were upgraded, false if problems
  */
 function _wp_upgrade_revisions_of_post( $post, $revisions ) {
  * @return bool true if the revisions were upgraded, false if problems
  */
 function _wp_upgrade_revisions_of_post( $post, $revisions ) {