Add 'mousescroll' option to control how many lines to scroll by when a
mouse wheel keycode is received. The mousescroll option controls both
horizontal and vertical scrolling. The option is a string in the format:
set mousescroll=direction:count,direction:count
Where direction is either "ver" or "hor", and count is a non negative
integer. If a direction is omitted, a default value is used. The default
values remain unchanged, that is 3 for vertical scrolling, and 6 for
horizontal scrolling. As such, the mousescroll default is "ver:3,hor:6".
Add mousescroll documentation
- Add option documentation in options.txt
- Add brief summary in quickref.txt
Update :help scroll-mouse-wheel
- Mention mousescroll option as a means of controlling scrolling.
- Remove obsolete suggestion to map scroll wheel keys to <C-U> to
scroll by a single line -- users should prefer the mousescroll option.
- Add some information about the consequences of remapping scroll wheel
keys (they lose their magic ability to affect inactive windows).
Update :help vim-differences
- Add brief mousescroll summary under Options
Add mousescroll tests
- Test option validation
- Test default mousescroll value and behavior
- Test fallback to default values
- Test mouse vertical and horizontal scrolling in normal mode
- Test mouse vertical and horizontal scrolling in insert mode
