Ticket #51170: 51170.2.diff

src/wp-admin/includes/class-wp-filesystem-ftpext.php

@@ -510 +510 @@
          * Gets the file size (in bytes).
          *
          * @since 2.5.0
-         * @since 6.1.0 Corrected the return value: while WP_Filesystem_Base::size()
-         *              is documented to return false on failure, ftp_size() returns -1.
          *
          * @param string $file Path to file.
-         * @return int Size of the file in bytes on success, -1 on failure.
+         * @return int|false Size of the file in bytes on success, false on failure.
          */
         public function size( $file ) {
-                return ftp_size( $this->link, $file );
+                $size = ftp_size( $this->link, $file );
+
+                return ( $size > -1 ) ? $size : false;
         }
 
         /**