commit https://github.com/vim/vim/commit/d424747d5821c2873e24d25d3407d08b25ea3443 Author: Bram Moolenaar <Bram@vim.org> Date: Mon Nov 2 13:28:59 2015 +0100 patch 7.4.905 Problem: Python interface can produce error "vim.message' object has no attribute 'isatty'". Solution: Add dummy isatty(), readable(), etc. (closes #464)

Tests for marks.

STARTTEST
:so small.vim
:" test that a deleted mark is restored after delete-undo-redo-undo
:/^\t/+1
:set nocp viminfo+=nviminfo
madduu
:let a = string(getpos("'a"))
:$put ='Mark after delete-undo-redo-undo: '.a
:/^\t/,$wq! test.out
ENDTEST

	textline A
	textline B
	textline C

Results: