LSP interaction error - 'semanticTokensProvider'

[jamestrew]

Howdy :wave:

I've been getting this error message when using Diffview: LSP[lua_ls]: Error SERVER_REQUEST_HANDLER_ERROR: "...local/share/nvim/runtime/lua/vim/lsp/semantic_tokens.lua:253: attempt to index field 'semanticTokensProvider' (a nil value)" I've only started using Diffview over frequently and I know lsp semantic highlighting is fairly new feature on neovim nightly and so maybe this is more of a neovim core issue but I want to bring this to your attention.

This only occurs when you disable semantic highlighting in your lsp config - more details below. Reproduce-ability of this bug is a little finicky and feels like it's maybe a timing issue between when lsp loads vs when the Diffview buffers are opened. That said I've found a way to reliably reproduce this using a slightly "non-typical" workflow.

Here are the details:

---

Neovim version:

NVIM v0.9.0-dev-970+gf006313e9
Build type: RelWithDebInfo
LuaJIT 2.1.0-beta3

I've experienced this on older versions of 0.9 nightly as well.

System info

Linux archlinux 6.1.11-arch1-1

Minimal config

Settings up Diffview and lspconfig - using lua_ls as an example as it supports semantic tokens. Note the setting of semanticTokensProvider = nil in the on_attach function. I believe this is the recommended way to disable semantic tokens. Commenting this line out resolves this issue.

```lua -- DO NOT change the paths and don't remove the colorscheme local root = vim.fn.fnamemodify("./.repro", ":p") -- set stdpaths to use .repro for _, name in ipairs({ "config", "data", "state", "cache" }) do vim.env[("XDG_%s_HOME"):format(name:upper())] = root .. "/" .. name end -- bootstrap lazy local lazypath = root .. "/plugins/lazy.nvim" if not vim.loop.fs_stat(lazypath) then vim.fn.system({ "git", "clone", "--filter=blob:none", "https://github.com/folke/lazy.nvim.git", lazypath, }) end vim.opt.runtimepath:prepend(lazypath) -- install plugins local plugins = { { "sindrets/diffview.nvim", dependencies = "nvim-lua/plenary.nvim", opts = { use_icons = false }, }, { "neovim/nvim-lspconfig", config = function() require("lspconfig").lua_ls.setup({ settings = { Lua = { runtime = { -- Tell the language server which version of Lua you're using (most likely LuaJIT in the case of Neovim) version = "LuaJIT", }, diagnostics = { -- Get the language server to recognize the `vim` global globals = { "vim" }, }, workspace = { -- Make the server aware of Neovim runtime files library = vim.api.nvim_get_runtime_file("", true), checkThirdParty = false, }, -- Do not send telemetry data containing a randomized but unique identifier telemetry = { enable = false, }, }, }, on_attach = function(client, bufnr) client.server_capabilities.semanticTokensProvider = nil end, }) end, }, -- add any other plugins here } require("lazy").setup(plugins, { root = root .. "/plugins", }) vim.cmd.colorscheme("habamax") ```

Steps to reproduce

1. mkdir -p /tmp/testing
2. cd /tmp/testing
3. git init
4. touch min.lua and paste in the minimal config from above
5. launch nvim with nvim -nu min.lua and confirm minimal config is working (including the lua lsp)
6. relaunch with nvim -nu min.lua "+DiffviewOpen"
7. observer 'semanticTokensProvider' error from above

Expected behavior

observer no lsp errors

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Let me know if you would like any additional details. I'm curious if other have experienced this as well.

[sindrets]

Looking at the error message and your description of the error, I highly doubt your issue has anything to do with this plugin. Seems like either the runtime module in core is neglecting to do a nil check, or the server capabilities is not following the spec. I would open an issue upstream.

[jamestrew]

Got it thanks. I'll report this upstream.