bug#56815: 29.0.50; Isearch lazy-highlight highlights too much when truncate-lines is in effect

[Juri Linkov]

>> This means using the same condition like in 'line-move'?
>>
>>                   (and
>>                    (or truncate-lines
>>                        (and (integerp truncate-partial-width-windows)
>>                             (< (window-total-width)
>>                                truncate-partial-width-windows))
>>                        (and truncate-partial-width-windows
>>                             (not (integerp truncate-partial-width-windows))
>>                             (not (window-full-width-p))))
>>                    ;; ...or if lines are truncated, this buffer
>>                    ;; doesn't have very long lines.
>>                    (long-line-optimizations-p))
>
> Yes, this is the (unfortunately complicated) way of determining
> whether the window has truncated lines.

Would it be possible to refactor this to a separate function?
I guess it could be in simple.el.  But what would be a good name?
Maybe 'truncate-lines-p'?