Problem: more places exist where curwin == prevwin, and it may even be
expected in some cases.
Solution: revert v9.1.0001, but document that it's possible instead.
(Sean Dewar)
I've had a change of heart for the following reasons:
- A quick 'n dirty [GitHub code search](https://github.com/search?q=%2F%28winnr%5C%28%5C%29%5Cs*%3D%3D%5Cs*winnr%5C%28%5B%27%22%5D%23%5B%27%22%5D%5C%29%7Cwinnr%5C%28%5B%27%22%5D%23%5B%27%22%5D%5C%29%5Cs*%3D%3D%5Cs*winnr%5C%28%5C%29%29%2F&type=code)
reveals some cases where it's expected in the wild.
Particularly, it made me aware `winnr() == winnr('#')` is possible when curwin
is changed temporarily during the evaluation of a &statusline expression item
(`%{...}`), and is used to show something different on the statusline
belonging to the previous window; that behaviour wasn't changed in v9.1.0001,
but it means curwin == prevwin makes sense in some cases.
- The definition and call sites of back_to_prevwin imply some expectation that
prevwin == wp (== curwin) is possible, as it's used to skip entering the
prevwin in that case.
- Prior to v9.1.0001, `:wincmd p` would not beep in the case that was patched in
v9.1.0001, but now does. That resulted in vim/vim#14047 being opened, as it affected
the CtrlP plugin.
I find it odd that `:wincmd p` had cases where it wouldn't beep despite doing
nothing, but it may be preferable to keep things that way (or instead also
beep if curwin == prevwin, if that's preferred).
- After more digging, I found cases in win_free_mem, enter_tabpage,
aucmd_restbuf and qf_open_new_cwindow where curwin == prevwin is possible
(many of them from autocommands). Others probably exist too, especially in
places where curwin is changed temporarily.
fixes: vim/vim#14047closes: vim/vim#14186d64801e913
ca7b603d02