Fix gj/gk in visual block mode

[orn688]

gj and gk did not work in visual block mode, because no motion for visual block mode corresponding to Move<Up/Down>ByScreenLine was implemented. Rather than truly moving up and down by a screen line, Move<Up/Down>ByScreenLineVisualBlockMode essentially just special-case MoveUp and MoveDown, following the example of Move<Up/Down>ByScreenLineVisualLineMode which also just moves by lines instead of by screen lines.

Fixes #1772.

I am quite inexperienced with this sort of repo (not to mention TypeScript in general) so I greatly appreciate any comments/suggestions for improvements. It seems like there should be a better way to implement this (e.g., by inheriting from MoveByScreenLine) but after trying a few such simpler approaches this was the first one that worked. Thanks for a great extension!

[xconverge]

I just tested this and this now kind of works...but it does not actually visual block on wrapped lines

and gj and gk all work for example, but if you are trying to visual block on a wrapped line section it does not properly

[orn688]

I was aware of that; I didn't try to make it actually work with wrapped lines, I just wanted it to actually respond to gk and gj in visual block mode (i.e., move up and down by one line), because that's all gk and gj do in visual line mode. Now that I think of it though, I guess that's not very sound reasoning since visual line mode selects lines at a time, not screen lines. I'll take a crack at making it actually work for wrapped lines.

[xconverge]

it is going to be pretty tricky, just a warning! The way we fake visual block mode is a bit tricky if I remember correctly... sorry I can't be of more help/guidance but we definitely appreciate the help so far!

[Chillee]

@oliver-newman Just out of curiosity, what's the motivation behind wanting this?

[orn688]

I have j and k mapped to gj and gk in non-insert modes so I can move vertically through wrapped lines (I'm not a fan of horizontal scrolling, so I prefer to keep wrapping on). gj and gk work in visual block mode in Vim, and I'm so used to just using j and k to move through wrapped lines at this point that it'd be a pain to either get used to using gj/gk explicitly or to using arrow keys when in visual block mode. The reason I submitted this pull request even without it properly working was that, for my purposes, moving up/down by lines rather than screen lines with gj and gk in visual block mode is a whole lot better than having gj and gk not work at all, even if it diverges slightly from Vim's functionality.

[xconverge]

@Chillee @oliver-newman I am actually OK with adding this for now and opening another issue for the case where it doesn't work (actual wrapped line situation). Since I think the gj to j binding is relatively common

[jpoon]

@oliver-newman, can you resolve the conflicts? Then we can merge this in.

[orn688]

@jpoon looks like the line endings got changed from LF to CRLF since I created this PR. I changed them to CRLF on my branch so I think it's all set to be merged, but let me know if there are any problems. Thanks!

[jpoon]

looks like the line endings got changed from LF to CRLF since I created this PR

Yeah, that was my f*ck up. Sorry.

[jpoon]

Thanks @oliver-newman!