Is it possible to trigger a snippet with a custom keymap instead of physically typing the trigger words?

[ziontee113]

First of all I'd like to thank LuaSnip developers for the Amazing Plugin!

I've been wondering for a while is it possible to trigger a snippet with a custom keymap.
For example, in Lua: "local xxx = yyy". It would be much easier to press a key combination like instead of physically typing out the trigger to expand the snippet!

Maybe we can implement a function like: callLuaSnippet("trigger")

With this type of custom mapping available, we could map any key combinations we want! And reduce our cognitive load!

[L3MON4D3]

Oh yes, that's very possible :D

ls.snip_expand(<some_snippet>) is used to expand a snippet at your cursor position, you'll need to store the snippets somewhere and address them somehow.
I think something like the following would be pretty flexible (not sure if it works exactly like this, I didn't test it).

First a module that maps key -> snippet.

-- in lua/keymap_snippets.lua

-- add snippet function-definitions first.
ls.setup_snip_env()

return {
	"snip1" = parse("trigger", "expanded with <C-D>")
}

Then a helper-function for the keymaps.

-- in your config:
local function map_snippet(keys, snippet_key)
	vim.keymap.set("i", keys, function()
		require("luasnip").snip_expand(require("keymap_snippets")[snippet_key])
	end)
end

map_snippet("<C-D>", "snip1")

You could also use the keys for accessing the snippets as key-combinations ({"<C-D>" = parse("trigger", "expanded with <C-D>")}), might be even cleaner.

[ziontee113]

Thank you! This is my current solution:

-- Autocmd for keymap triggered snippets --
local autocmd = vim.api.nvim_create_autocmd
local augroup = vim.api.nvim_create_augroup
local map = vim.keymap.set
local opts = { noremap = true, silent = true }

local snippets = { a bunch of snippets }
local autosnippets = { a bunch of autosnippets }

local group = augroup("Lua Snippets", { clear = true })
autocmd("BufEnter", {
	pattern = "*.lua",
	group = group,
	callback = function()
		map({ "i" }, "jj", function()
			ls.snip_expand(vim.deepcopy(snippets[1]))
		end, opts)
	end,
})

return snippets, autosnippets

luasnip.jj.mp4

I'm currently using require("luasnip.loaders.from_lua").load({ paths = "~/.config/nvim/snippets/" }) to hot reload snippets. 🔥
To reload those autocmds I use :luafile %<cr>, go to some other buffer then go back.

Is the "BufEnter" event bad for this usecase? Or it it a good one? 🤔

Also do you think it is possible to make the snippets files in the subfolders also hot-reloadable? Currently the main files are hot-reloaded at save. But the ones in the subfolders isn't. 😄

[L3MON4D3]

Nice, or like that for snippets that should be regularly expandable too.
I don't really get the autocmd; can't you just call map directly?
Also, this is one of the few places where you don't need the deepcopy, the snippet is copied in snip_expand :P

The files in subfolder not being reloadable is surprising and definitely a bug. I'll have a look at it.

[ziontee113]

Thank you :) The autocmd is for different filetypes.
In my snippets folder I have javascript.lua, lua.lua, all.lua, etc...
In my *.js files I can map jj to console.log() and in lua I can have jj for local {} = {} for example 👍

[L3MON4D3]

Ahh ofc, that makes sense.
BufEnter seems pretty good for that usecase, I can't think of a better way👍

[tjex]

Hoping I can get some help with this.

I'm also trying to get this working, but has something perhaps changed in the api since last posted?
I feel like I'm doing everything correct:

~/.config/nvim/lua/tjex/keybind-snips.lua:

ls.setup_snip_env()

return {
	s(
	"print",
	fmt(
	    [[
                 fmt.Println({})
            ]],
	    { i(1) }
         )
	),
}

~/.config/nvim/after/plugin/luasnip.lua:

require("luasnip.loaders.from_lua").load { paths = "~/.config/nvim/snippets/" }

-- other configs

local function map_snippet(keys, snippet_key)
	vim.keymap.set("i", keys, function()
		require("luasnip").snip_expand(require("tjex.keybind-snips")[snippet_key])
	end)
end

map_snippet("<C-k>", "print")

But I get this error message:

E5108: Error executing lua: ...nvim/site/pack/packer/start/LuaSnip/lua/luasnip/init.lua:229: attempt to index local 'snippet' (a nil value)
stack traceback:
        ...nvim/site/pack/packer/start/LuaSnip/lua/luasnip/init.lua:229: in function 'snip_expand'
        [string ":source (no file)"]:42: in function 'callback'
        ...site/pack/packer/start/nvim-cmp/lua/cmp/utils/keymap.lua:159: in function 'callback'
        ...m/site/pack/packer/start/nvim-cmp/lua/cmp/utils/misc.lua:13: in function 'fallback'
        ...te/pack/packer/start/nvim-cmp/lua/cmp/config/mapping.lua:215: in function 'on_keymap'
        ...re/nvim/site/pack/packer/start/nvim-cmp/lua/cmp/core.lua:145: in function 'callback'
        ...site/pack/packer/start/nvim-cmp/lua/cmp/utils/keymap.lua:133: in function <...site/pack/packer/start/nvim-cmp/lua/cmp/utils/keymap.lua:127>

[L3MON4D3]

Ah, print is nil in the table returned by the module.
Either make it print = s(... or call map_snippet with 1 instead of "print" (but the first option is better imo)

[tjex]

yus! Thanks so much.

Here is my more hacky approach to specify file type specific mappings too, if it helps or gives ideas to others.
pcall isn't working though for some reason 🤷‍♂️. Don't get any error when executing on filetype I don't have a keysnips-<lang>.lua for. But at least I can name different print functions as "print" in different keysnips-<lang>.lua, allowing me to keep the same keybind.

~/.config/nvim/after/plugin/luasnip.lua:

local function map_snippet(keys, snippet_key)
	vim.keymap.set("i", keys, function()
		local ftype = vim.bo.filetype
		local function keybind_snip()
			require("luasnip").snip_expand(require("snippets.keysnips-" .. ftype)[snippet_key]) -- nvim/lua/keybind-snips
		end
        local snip_found, _ = pcall(keybind_snip)
		if not snip_found then
			print("no keybind snippets for this filetype")
			return
		end
	end)
end

~/.config/nvim/lua/snippets:

.
├── all.lua
├── bash.lua
├── go.lua
├── keysnips-go.lua
├── lua.lua
└── markdown.lua

[emilBeBri]

YES have been looking for this for some time, your solution works great @tjex , thanks!