From dd45b9c2cab9eba2bd960ede6545b348aa823eb6 Mon Sep 17 00:00:00 2001
From: azaozz <azaozz@1a063a9b-81f0-0310-95a4-ce76da25c4cd>
Date: Thu, 1 Mar 2012 00:18:26 +0000
Subject: [PATCH] Don't pass non-existing rtl stylesheet to TinyMCE, update
 phpdoc for  add_editor_style(), see #19437

git-svn-id: http://svn.automattic.com/wordpress/trunk@20059 1a063a9b-81f0-0310-95a4-ce76da25c4cd
---
 wp-includes/class-wp-editor.php | 21 +++++++++++----------
 wp-includes/theme.php           |  8 ++++++--
 2 files changed, 17 insertions(+), 12 deletions(-)

diff --git a/wp-includes/class-wp-editor.php b/wp-includes/class-wp-editor.php
index af69b0870..fdd4fbf91 100644
--- a/wp-includes/class-wp-editor.php
+++ b/wp-includes/class-wp-editor.php
@@ -328,24 +328,25 @@ final class _WP_Editors {
 					$mce_css = array();
 					$editor_styles = array_unique($editor_styles);
 					$style_uri = get_stylesheet_directory_uri();
-					if ( ! is_child_theme() ) {
-						foreach ( $editor_styles as $file )
+					$style_dir = get_stylesheet_directory();
+
+					foreach ( $editor_styles as $key => $file ) {
+						if ( $file && file_exists( "$style_dir/$file" ) ) {
 							$mce_css[] = "$style_uri/$file";
-					} else {
-						$style_dir    = get_stylesheet_directory();
+							$editor_styles[$key] = '';
+						}
+					}
+
+					if ( is_child_theme() ) {
 						$template_uri = get_template_directory_uri();
 						$template_dir = get_template_directory();
 
 						foreach ( $editor_styles as $file ) {
-							if ( file_exists( "$template_dir/$file" ) )
+							if ( $file && file_exists( "$template_dir/$file" ) )
 								$mce_css[] = "$template_uri/$file";
 						}
-
-						foreach ( $editor_styles as $file ) {
-							if ( file_exists( "$style_dir/$file" ) )
-								$mce_css[] = "$style_uri/$file";
-						}
 					}
+
 					$mce_css = implode( ',', $mce_css );
 				} else {
 					$mce_css = '';
diff --git a/wp-includes/theme.php b/wp-includes/theme.php
index fcc1f6155..c1b2220d6 100644
--- a/wp-includes/theme.php
+++ b/wp-includes/theme.php
@@ -1334,10 +1334,14 @@ body.custom-background { <?php echo trim( $style ); ?> }
  * the theme root. It also accepts an array of stylesheets.
  * It is optional and defaults to 'editor-style.css'.
  *
- * Supports RTL stylesheets automatically by searching for the -rtl prefix, e.g.
- * editor-style-rtl.css. If an array of stylesheets is passed to add_editor_style(),
+ * This function automatically adds another stylesheet with -rtl prefix, e.g. editor-style-rtl.css.
+ * If that file doesn't exist, it is removed before adding the stylesheet(s) to TinyMCE.
+ * If an array of stylesheets is passed to add_editor_style(),
  * RTL is only added for the first stylesheet.
  *
+ * Since version 3.4 the TinyMCE body has .rtl CSS class.
+ * It is a better option to use that class and add any RTL styles to the main stylesheet.
+ *
  * @since 3.0.0
  *
  * @param mixed $stylesheet Optional. Stylesheet name or array thereof, relative to theme root.