Ticket #18599: 18599.3.patch

wp-admin/includes/class-wp-themes-list-table.php

@@ -175 +175 @@
 ?>
                 <a href="<?php echo $preview_link; ?>" class="<?php echo $thickbox_class; ?> screenshot">
 <?php if ( $screenshot ) : ?>
-                        <img src="<?php echo $theme_root_uri . '/' . $stylesheet . '/' . $screenshot; ?>" alt="" />
+                        <img src="<?php echo esc_url( _get_theme_screenshot_url( $stylesheet_dir, $template_dir, $screenshot ) ); ?>" alt="" />
 <?php endif; ?>
                 </a>
 <h3><?php

wp-admin/themes.php

@@ -81 +81 @@
 <h3><?php _e('Current Theme'); ?></h3>
 <div id="current-theme">
 <?php if ( $ct->screenshot ) : ?>
-<img src="<?php echo $ct->theme_root_uri . '/' . $ct->stylesheet . '/' . $ct->screenshot; ?>" alt="<?php _e('Current theme preview'); ?>" />
+<img src="<?php echo esc_url( _get_theme_screenshot_url( $ct->stylesheet_dir, $ct->template_dir, $ct->screenshot ) ); ?>" alt="<?php _e('Current theme preview'); ?>" />
 <?php endif; ?>
 <h4><?php
         /* translators: 1: theme title, 2: theme version, 3: theme author */

wp-includes/theme.php

@@ -293 +293 @@
                 $template    = $theme_data['Template'];
                 $stylesheet  = dirname($theme_file);
 
-                $screenshot = false;
-                foreach ( array('png', 'gif', 'jpg', 'jpeg') as $ext ) {
-                        if (file_exists("$theme_root/$stylesheet/screenshot.$ext")) {
-                                $screenshot = "screenshot.$ext";
-                                break;
-                        }
-                }
-
                 if ( empty($name) ) {
                         $name = dirname($theme_file);
                         $title = $name;
@@ -393 +385 @@
                 if ( empty($stylesheet_dir) )
                         $stylesheet_dir = '/';
 
+                $screenshot = false;
+                foreach ( array('png', 'gif', 'jpg', 'jpeg') as $ext ) {
+                        if ( file_exists("$stylesheet_dir/screenshot.$ext") || file_exists("$template_dir/screenshot.$ext") ) {
+                                $screenshot = "screenshot.$ext";
+                                break;
+                        }
+                }
+
                 // Check for theme name collision.  This occurs if a theme is copied to
                 // a new theme directory and the theme header is not updated.  Whichever
                 // theme is first keeps the name.  Subsequent themes get a suffix applied.
@@ -1989 +1989 @@
 
 add_action( 'delete_attachment', '_delete_attachment_theme_mod' );
 
+/**
+ * Retrieve screenshot URL for a theme.
+ *
+ * If a child theme screenshot is missing, the one from a parent theme is used.
+ *
+ * @access private
+ * @since 3.3.0
+ */
+function _get_theme_screenshot_url( $stylesheet_dir, $template_dir, $screenshot ) {
+        $screenshot_url = false;
+
+        if ( file_exists("$stylesheet_dir/$screenshot") )
+                $screenshot_url = str_replace( WP_CONTENT_DIR, content_url(), "$stylesheet_dir/$screenshot" );
+        elseif ( file_exists("$template_dir/$screenshot") )
+                $screenshot_url = str_replace( WP_CONTENT_DIR, content_url(), "$template_dir/$screenshot" );
+
+        return $screenshot_url;
+}
+
 ?>