Implement missing functionality for moving lines up/down by count

[OptimusCrime]

Hello,

I came across some useful mappings, like the two below:

nnoremap [e  :<c-u>execute 'move -1-'. v:count1<cr>
nnoremap ]e  :<c-u>execute 'move +'. v:count1<cr>

These mappings move the current line up or down, which could be useful from time-to-time. The mappings are supposed to take a count, but the count part of the mapping does not work as expected. I assume that this is because the v:count1 variable is not implemented.

Edit: Hmm. I just came across VimVariableServiceBase.kt , and it looks like these variables are indeed implemented, but the count is wrong.

[citizenmatt]

Unfortunately, the comment just above this line is relevant:

ideavim/vim-engine/src/main/kotlin/com/maddyhome/idea/vim/vimscript/services/VimVariableServiceBase.kt

Lines 216 to 217 in e13deb4

	// Note that the v:count variables might be incorrect in scenarios other than mappings, when there is a command in
	// progress. However, I've only seen it used inside mappings, so don't know

The count variables are calculated by looking at CommandBuilder, but the count is only valid while the command builder is still in progress. Normally, this is fine. When a command completes (like 3w or 5dw), the CommandBuilder (and count) is reset, and the command's action handler is invoked. Because it's a complete command, there are obviously no expressions to evaluate. If expression mappings are involved, they are invoked/evaluated before the command is complete, so the builder (and count) is still valid.

AFAICT, the only exception to this is when handling the <CR> in a command line. This is a complete command, so the CommandBuilder is reset, and the ProcessExEntryAction handler evaluates the command. The count variable looks at the CommandBuilder and sees zero.

I'm not sure of the best way to solve this. While we get the count passed to the action handler, I don't see a nice way of making it available to VariableService.

Could you add a ticket so we've got the scenario logged, please?

[OptimusCrime]

Thank you for your answer. Does this mean that the mapping that I found is not guaranteed to work in vim either, or is this a ideavim specific problem? Are there other ways of achieving the count logic with what is already implemented in ideavim?

I will create a ticket for this when I have time.

[citizenmatt]

Probably IdeaVim specific. The Vim docs say "The count given for the last Normal mode command", while IdeaVim treats it as the count for the current in-progress command. So I think we should figure out how to get IdeaVim to handle this properly. I can't think of a workaround for now, sorry.