bug#59486: completion-auto-wrap disobeyed by vertical navigation

[Juri Linkov]

>> >> minibuffer-previous-* are intended to navigate the completion list
>> >> horizontally while the minibuffer is active, and 
>> >> minibuffer-previous-line-*
>> >> vertically.
>> >
>> > Then the names could be simplified as minibuffer-up-line and
>> > minibuffer-down-line.  It will also make the names less confusing, IMO.
>>
>> It's not only about the minibuffer, but also about completions,
>> so the commands names should also include the word "completion".
>
> minibuffer-up-completions-line is still shorter and less confusing.

'minibuffer-previous-line-completion' is named after 'previous-line'
that is not named 'up-line'.  There are 'left-char', 'left-word', etc.
only in horizontal direction, but no 'up-line' in vertical direction.
So it makes no sense to propagate this inconsistency to completion
command names where there are only 'previous-completion', but no
'left-completion'.

>> It does the same as icomplete-vertical-mode where the arrow keys
>> are not confusing.
>
> icomplete-vertical-mode is a an opt-in feature, so what it does is less
> relevant to the issue at point, IMO.

The proposed feature is also opt-in.