fix: columnar_menu create_string with quoted suggestions

[blindFS]

This is a stopgap for nushell/nushell#12680, nushell/nushell#13951, nushell/nushell#13630, nushell/nushell#15302.

Fuzzy matching will need more care, and I think @ysthakur knows how to fix that.

nushell/nushell#13951 also exposes another bug in directory_completion, i.e. not doing quoting, which is handled properly in file_completion.

[ysthakur]

Thanks, it'd be good to have at least a temporary fix for this bug. Could you also modify ide_completions? It has the same problem with split_at.

For fuzzy completions, you can iterate over the graphemes in every suggestion and highlight every grapheme that contains a character whose index is less than shortest_base.len(). I was working on a function to do that here. That one's more complicated than what you need to do because it takes a list of match indices rather than just highlight a prefix (the function's from #798).

[blindFS]

@ysthakur Thanks for the reminder! That's interesting, because I was looking at #839 and thought only columnar_menu had the problem, and I also greped create_string in the repo.

It turns out that ide_menu already got the width -> len fix somewhere else and the function name is create_value_string, LoL.

[blindFS]

For fuzzy completions, you can iterate over the graphemes in every suggestion and highlight every grapheme that contains a character whose index is less than shortest_base.len(). I was working on a function to do that here. That one's more complicated than what you need to do because it takes a list of match indices rather than just highlight a prefix (the function's from #798).

I was hoping for a systematic solution for both issues, I'm not sure if nucleo_matcher can directly return the matching indices while calculating the score so that we don't need some extra overhead here in reedline.