Nodes are skipped in long snippets when nested expansion

[Gargantuar314]

I have the following snippet file:

return {}, {

s({
    trig = 'tshort',
    name = 'tikzcd short exact sequence'
}, {
    i(1), t(' \\ar[r'), i(2), t({']', '& '}),
    i(3), t(' \\ar[r'), i(4), t({']', '& '}),
    i(5), t(' \\ar[r'), i(6), t({']', '& '}),
    i(7), t(' \\ar[r'), i(8), t({']', '& '}),
    i(9)
}),

s({
    trig = 'tlong',
    name = 'tikzcd term of long exact sequence',
}, {
    t({'& '}), i(1), t(' \\ar[r'), i(2), t(']')
}),

s({
    trig = 'ie',
    name = 'i.e.'
}, {
    t('i.\\,e.,')
})
}

If I type tshort or tlong, then I can skip through the InsertNodes as usual with <Tab>. However, if I type tshort and then expand ie in the first node (or any snippet, for that matter), pressing <Tab> inserts a literal tab character instead of jumping to the next node. This problem doesn't appear when using tlong, so I suspect that the length of the node is a problem.

Is this a bug? Or should I fix something?

[L3MON4D3]

Odd!
Could you share your luasnip config? The keymap for <Tab> especially, I think there may be an issue there..
At least for me, everything works as expected

[Gargantuar314]

Sure! Here is the luasnip keymap config:

local ls = require('luasnip')
local function default_action(str)
    key = vim.api.nvim_replace_termcodes(str, true, false, true)
    vim.api.nvim_feedkeys(key, 'n', false)
end

-- Tab to trigger snippet or jump to next node
vim.keymap.set({ 'i' }, '<Tab>', function()
    if ls.expand_or_jumpable() then
        ls.expand_or_jump()
    else
        default_action('<Tab>')
    end
end, { silent = true })
-- Shift + Tab to jump to previous node
vim.keymap.set({ 'i', 's' }, '<S-Tab>', function() ls.jump(-1) end, { silent = true })

-- Cycle through choice node
vim.keymap.set({ 'i', 's' }, '<C-E>', function()
    if ls.choice_active() then
		ls.change_choice(1)
    else
        default_action('<C-E>')
	end
end, { silent = true })

Here my luasnip plugin config (I use lazy.nvim):

require("luasnip").setup{
    history = false, -- Cannot jump back to already triggered snippets
    region_check_events = 'CursorMoved', -- Outside snippet if cursor moved
    delete_check_events = { 'TextChanged', 'TextChangedI' }, -- Delete jumps
    enable_autosnippets = true, -- Auto triggered snippets
    store_selection_keys = '<Tab>' -- Snippets with visual mode
}

require("luasnip.loaders.from_lua").load({ paths = "./snippet" })

And the snippet definitions are stored in ./snippet/tex.lua.

[Gargantuar314]

After some experimentation, this problem doesn't happen if the ie snippet is expanded at any other node, say, i(3), of tshort. I think the problem is that the tshort snippet doesn't have a leading text node before the first insert node.

Maybe this is related: #1288. In this issue, it is explained that nested expansion will consume the character before the child snippet so that the parent snippet is broken.