Great news Eli!!!


It took me a while, but I believe I’ve figured it out!


I made a video comparing the behavior before and after applying this
patch. I think a visual demonstration is more effective than words
alone, as it highlights the many visual improvements.


Here’s the video link: https://www.youtube.com/watch?v=ni0l6PruJEs


This patch introduces two new features that improve
icomplete-vertical-mode, which are explained below:


1.) Improve feature provided by `icomplete-in-buffer'.
    If user, besides setting `icomplete-in-buffer' to t, also set the
    new `icomplete-vertical-in-buffer-adjust-list' to t, the following are fixed/ improved:

Without the new `icomplete-vertical-in-buffer-adjust-list':

* wrapped lines   - completion candidates on different columns always shows candidates at column 0
* wrapped lines   - completion candidates on different lines always shows candidates at column 0
* wrapped lines   - completion candidates close to the end of buffer won't be printed
* truncated lines - completion candidates on different columns always shows candidates at column 0
* truncated lines - completion candidates on horizontally scrolled windows won't appear on buffer
                        as they're on column 0
* truncated lines - completion candidates close to the end of buffer wont be shown


With the new `icomplete-vertical-in-buffer-adjust-list':

* wrapped lines   - fix    : completion candidates on different columns will always be printed
                                 under the cursor
* wrapped lines   - feature: completion candidates on different columns close to the end
                                 of the buffer will adjust so they stay visible
* wrapped lines   - fix:   : completion candidates on different lines always be printed under
                                 the cursor
* wrapped lines   - fix    : if icomplete-prospects-height won't fit from current line to the
                                 end of vertical space, our window will be scrolled so we have at
                                 least this amount of lines. This ensures our candidates list is
                                 always visible
* truncated lines - fix    : completion candidates on different columns will always be printed
                                 under the cursor
* truncated lines - feature: completion candidates on different columns close to the end
                                 of the buffer will adjust so they stay visible even when we scroll
                                 horizontally
* truncated lines - feature: completion candidates on horizontally scrolled windows will be
                                 printed under the cursor
* wrapped lines   - feature: if icomplete-prospects-height won't fit from current line to the
                                 end of vertical space, our window will be scrolled so we have at
                                 least this amount of lines. This ensures our candidates list is
                                 always visible
* from wrapped    - feature: if we are on wrapped lines and manually horiontal scroll, the lines
      to truncated               will become automatically truncated, in this case, all the features
                                 above still works from either mode (wrapped or truncated).



Attached is the latest (and hopefully final) version of this patch.