Ticket #17320: 17320.diff

Index: wp-includes/post.php
===================================================================
--- wp-includes/post.php        (revision 17848)
+++ wp-includes/post.php        (working copy)
@@ -506,12 +506,26 @@
  * @since 3.1.0
  * @uses has_term()
  *
- * @param string $format The format to check for
+ * @param string|array $format The format to check for
  * @param object|id $post The post to check. If not supplied, defaults to the current post if used in the loop.
  * @return bool True if the post has the format, false otherwise.
  */
 function has_post_format( $format, $post = null ) {
-       return has_term('post-format-' . sanitize_key($format), 'post_format', $post);
+       if ( is_array( $format ) ) {
+               $format_prefixed = array();
+               foreach ( $format as $f ) {
+                       if ( !is_string( $f ) ) {
+                               unset( $format_prefixed );
+                               unset( $f );
+                               return false;
+                       }
+                       $format_prefixed[] = 'post-format-' . sanitize_key( $f );
+               }
+               unset( $format_prefixed );
+               unset( $f );
+               return has_term( $format_prefixed, 'post_format', $post );
+       }
+       return has_term( 'post-format-' . sanitize_key( $format ), 'post_format', $post );
 }
 
 /**