In `wp_prepare_attachment_for_js()`, when setting `filename`, call `wp_basename()` on the result of `get_attached_file()`, not `WP_Post->guid`. `guid` can be set to the result `get_permalink()`, which is not a file path.

Props daxelrod.
Fixes #32531.

Built from https://develop.svn.wordpress.org/trunk@32914


git-svn-id: http://core.svn.wordpress.org/trunk@32885 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/media.php

@@ -2720,7 +2720,7 @@ function wp_prepare_attachment_for_js( $attachment ) {
 	$response = array(
 		'id'          => $attachment->ID,
 		'title'       => $attachment->post_title,
-		'filename'    => wp_basename( $attachment->guid ),
+		'filename'    => wp_basename( get_attached_file( $attachment->ID ) ),
 		'url'         => $attachment_url,
 		'link'        => get_attachment_link( $attachment->ID ),
 		'alt'         => get_post_meta( $attachment->ID, '_wp_attachment_image_alt', true ),

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.3-alpha-32913';
+$wp_version = '4.3-alpha-32914';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.