Loading snippets by snippet-filetype subdirectories while using Lazy.nvim doesn't work

[hrcHarry]

Hi

I'm migrating plugin manager from packer to Lazy.nvim, and I got some issue about Luasnip.

I would like to organize the snippets by filetype subdirectories (see ejmastnak's page -- Snippet filetype subdirectories).

In packer time, I just have the following line in some .lua file which will be loaded by require(), and then filetype subdirectories purpose will be done.

require("luasnip.loaders.from_lua").lazy_load({paths = "~/AppData/Local/nvim/lua/plugins_config/luasnip/additional_config/languages"})

where the structure after luasnip directory is

luasnip
└─ additional_config
|  └─ languages
|     └─ c
|     |  └─  (some .lua files)
|     └─ tex
|        └─  (some .lua files)
└─ init.lua   (for packer)

The .lua files in c/ and tex/ directories are like

local ls = require("luasnip")
local s = ls.snippet
local fmta = require("luasnip.extras.fmt").fmta

return {
  s( {--[[ table 1 --]]},
     fmta([[ strings ]], 
     { --[[ table 2 --]]}
  )
}

Then, whenever opening .c or .tex file, the snippets work.

Now using Lazy.nvim, I set luasnip/init.lua as follows; it doesn't work when opening .c and .tex file.

return {
  "L3MON4D3/LuaSnip",
  version = "v2.*",
  build = "make install_jsregexp",
  opts = {
    -- some opts
  },
  init = function()  -- replace 'init' with 'config' does not work as well
    require("luasnip.loaders.from_lua").lazy_load({paths = "~/AppData/Local/nvim/lua/plugins_config/luasnip/additional_config/languages"})
  end,
}

When opening a .c file, for example, lua print(vim.inspect(require("luasnip").get_snippet_filetypes())) gives the result { "c", "all" } --- if I don't get it wrong, it tells us the filetype of the open file is of c, right? But I cannot trigger the snippet in this open file.

Furthermore, it also doesn't work even though I put require("luasnip.loaders.from_lua").lazy_load({paths = "~/AppData/Local/nvim/lua/plugins_config/luasnip/additional_config/languages"}) in ~/AppData/Local/nvim/init.lua.

Could someone help? Thanks!

Additional info

OS: Windows 10
--
:version
NVIM v0.9.5
Build type: RelWithDebInfo
LuaJIT 2.1.1703942320
Compilation: C:/Program Files (x86)/Microsoft Visual Studio/2019/Enterprise/VC/Tools/MSVC/14.29.30133/bin/Hostx64/x64/cl.exe /MD /Zi /O2 /Ob1  -W3 -wd4311 -wd4146 -DUNIT_TESTING -D_CRT_SECURE_NO_WARNINGS -D_CRT_NONSTDC_NO_DEPRECATE -D_WIN32_WINNT=0x0602 -DMSWIN -DINCLUDE_GENERATED_DECLARATIONS -ID:/a/neovim/neovim/.deps/usr/include/luajit-2.1 -ID:/a/neovim/neovim/.deps/usr/include -ID:/a/neovim/neovim/.deps/usr/include -ID:/a/neovim/neovim/build/src/nvim/auto -ID:/a/neovim/neovim/build/include -ID:/a/neovim/neovim/build/cmake.config -ID:/a/neovim/neovim/src -ID:/a/neovim/neovim/.deps/usr/include -ID:/a/neovim/neovim/.deps/usr/include -ID:/a/neovim/neovim/.deps/usr/include -ID:/a/neovim/neovim/.deps/usr/include -ID:/a/neovim/neovim/.deps/usr/include -ID:/a/neovim/neovim/.deps/usr/include -ID:/a/neovim/neovim/.deps/usr/include

   system vimrc file: "$VIM\sysinit.vim"
  fall-back for $VIM: "C:/Program Files (x86)/nvim/share/nvim"

[hrcHarry]

Finally, I resolved it.

Summary:

1. config field in luasnip/init.lua must have require("luasnip").setup(opts). In this case, for example,

return {
  "L3MON4D3/LuaSnip",
  version = "v2.*",
  build = "make install_jsregexp",
  opts = {
    -- some opts
  },
  config = function()  
    require("luasnip").setup(opts)   -- This is necessary.
    require("luasnip.loaders.from_lua").lazy_load({paths = "~/AppData/Local/nvim/lua/plugins_config/luasnip/additional_config/languages"})
  end,
}

2. When you need to load .tex snippet,
   (a) if VimTeX has not been installed yet, then the filetype of .tex file will be plaintex, so the name of the directory containing snippets .lua files must be plaintex rather than tex. In this cae, that is

luasnip
└─ additional_config
|  └─ languages
|     └─ c
|     |  └─  (some .lua files)
|     └─ plaintex     % NOT 'tex'
|        └─  (some .lua files)
└─ init.lua   (for Lazy.nvim)

(b) if VimTeX has been installed, then the filetype of .tex file will be tex, so the name of the directory containing snippets .lua files must be tex as mentioned in the question.

Open the file of certain filetype and execute :lua print(vim.inspect(require("luasnip").get_snippet_filetypes())) to check whether the filetype you set is correct. See document>Troubleshooting>Adding Snippets>Loaders>Filetypes

Hope this helps.