Consecutive win_move_statusline() calls don't work properly after printing multiline message

[zeertzjq]

Neovim version (nvim -v)

v0.9.0-dev-284+g0faf007a2

Vim (not Nvim) behaves the same?

No

Operating system/version

Arch Linux

Terminal name/version

kitty 0.26.5

$TERM environment variable

xterm-kitty

Installation

build from repo

How to reproduce the issue

1. Run nvim --clean
2. Source the following file:

echo "\n"
call win_move_statusline(0, -4)
call win_move_statusline(0, 4)

3. Press Enter

Expected behavior

cmdheight is 1

Actual behavior

cmdheight is 4

[zeertzjq]

This is related to these lines in message.c:

neovim/src/nvim/message.c

Lines 199 to 204 in 0faf007

	if (msg_grid.chars && cmdline_row < msg_grid_pos) {
	// TODO(bfredl): this should already be the case, but fails in some
	// "batched" executions where compute_cmdrow() use stale positions or
	// something.
	cmdline_row = msg_grid_pos;
	}