Add support for start_mode

[MarcelRobitaille]

Implement start_mode. It's like start_in_insert, but more flexible.

Context

Implement #174

Description

I added start_mode. I kept start_in_insert for backwards compatibility.

Test Plan

I tried each value of start_mode with a default value and without. I also added automated tests of the backwards compatibility of start_in_insert.

[stevearc]

Left some comments. Also make sure that as you're testing this you test different combinations of your starting mode + the start_mode option. For example, try running vim.ui.input when you're already in visual mode and with start_mode = "insert". Try that for all the permutations to make sure that the start_mode is respected in all cases and there's no weirdness.

[stevearc]

Would be great to also provide support for select mode (see :help Select-mode)

[MarcelRobitaille]

Do you know a good way to get into select mode? The best option to me reading the help is CTRL-G since it doesn't require changing any settings, but it's not working for me. It works if I do it manually (set start_mode to visual and press CTRL-G) but not using

    vim.api.nvim_command("normal! v$")
    local ctrl_g = vim.api.nvim_replace_termcodes("<C-g>", true, false, true)
    vim.api.nvim_feedkeys(ctrl_g, "v", true)

[stevearc]

This seems to work for me

vim.cmd("normal! 0vg_")
vim.api.nvim_feedkeys(vim.api.nvim_replace_termcodes("<C-g>", true, false, true), "n", true)

[MarcelRobitaille]

This snippet puts me in visual mode. Shouldn't it be "v", not "n"? I thought it was a visual mode mapping.

[MarcelRobitaille]

I'm still not sure what to do here.

[stevearc]

I just tried the snippet that I gave you on your branch and it works for me. Are you sure that it's not working? Is it possible that something else in your config is interfering with it?

[MarcelRobitaille]

You're right. I just tried this, and I got into select mode.

nvim -u NORC --noplugin -c 'lua vim.cmd("normal! 0vg_")' -c 'lua vim.api.nvim_feedkeys(vim.api.nvim_replace_termcodes("<C-g>", true, false, true), "n", true)'

[MarcelRobitaille]

Select mode is now working for me. What exactly is the advantage? Reading help, I see that enter deletes everything and goes into insert mode, but in our case enter confirms the input.

[MarcelRobitaille]

Thanks for the quick review. I addressed some of the comments. I left some to do because I'd like some feedback first.

[stevearc]

Only question you were waiting on was about select mode, right?

[MarcelRobitaille]

Yes unless you also want to have a look at how I added back restoring the previous mode.

[stevearc]

I just tried the snippet that I gave you on your branch and it works for me. Are you sure that it's not working? Is it possible that something else in your config is interfering with it?

[stevearc]

This looks good. Once you add support for select mode and fix the CI, it's good to merge!

[stevearc]

Still some CI failures

[MarcelRobitaille]

I'm having some trouble with the tests. I saw some comments that startinsert doesn't work in tests, but even if I do util.feedkeys({"i"}), vim.api.nvim_get_mode().mode always says it's in normal mode. Is it not possible to change the mode at all in tests? I'm new to this headless neovim testing.

[stevearc]

Headless testing isn't great; as you've discovered there are some difficult inconsistencies to deal with. Unfortunately I don't have any better idea what hacks will help bypass this. Just try a few things, see if you can get something working, and if not no worries I won't block the PR for lack of tests.

[MarcelRobitaille]

Since insert mode doesn't work well, I mocked set_mode and restore_mode.

[stevearc]

One nit and still some styling inconsistencies

[stevearc]

Great job! Thanks for the PR!

[MarcelRobitaille]

No, thank you! I really appreciate how patient you were with me.