Add many packages for neovim, and config for them

rcfiles/neovim.lua

@@ -36,6 +36,130 @@ vim.keymap.set('n', '<leader>fb', tbuiltin.buffers, {})
 vim.keymap.set('n', '<leader>fh', tbuiltin.help_tags, {})
 vim.keymap.set('n', '<leader>fs', tbuiltin.spell_suggest, {})
 
+-- Mason (tool manager) setup
+-- we want rust-analyzer and codelldb
+require("mason").setup({
+  ui = {
+    icons = {
+      package_installed = "✔️",
+      package_pending = "🔄",
+      package_uninstalled = "🌐"
+    }
+  }
+})
+require("mason-lspconfig").setup()
+
+-- General LSP settings
+-- from https://rsdlt.github.io/posts/rust-nvim-ide-guide-walkthrough-development-debug/
+local sign = function(opts)
+  vim.fn.sign_define(opts.name, {
+    texthl = opts.name,
+    text = opts.text,
+    numhl = ''
+  })
+end
+
+sign({name = 'DiagnosticSignError', text = '🛑'})
+sign({name = 'DiagnosticSignWarn', text = '⚠️'})
+sign({name = 'DiagnosticSignHint', text = '💭'})
+sign({name = 'DiagnosticSignInfo', text = '🗒️'})
+
+vim.diagnostic.config({
+    virtual_text = false,
+    signs = true,
+    update_in_insert = true,
+    underline = true,
+    severity_sort = false,
+    float = {
+        border = 'rounded',
+        source = 'always',
+        header = '',
+        prefix = '',
+    },
+})
+
+vim.cmd([[
+set signcolumn=yes
+autocmd CursorHold * lua vim.diagnostic.open_float(nil, { focusable = false })
+]])
+
+-- Rust tools for Rust-specific LSP
+local rt = require("rust-tools")
+rt.setup({
+  server = {
+    on_attach = function(_, bufnr)
+      -- ctrl + space for hover actions
+      vim.keymap.set("n", "<C-space>", rt.hover_actions.hover_actions, { buffer = bufnr })
+      -- ,a for code actions
+      vim.keymap.set("n", "<Leader>a", rt.code_action_group.code_action_group, { buffer = bufnr })
+    end,
+  }
+})
+
+-- set up treesitter
+require('nvim-treesitter.configs').setup {
+  auto_install = false,
+  ident = { enable = true }, 
+  rainbow = {
+    enable = true,
+    extended_mode = true,
+    max_file_lines = nil,
+  }
+}
+
+-- completion setup
+local cmp = require 'cmp'
+cmp.setup({
+  -- Enable LSP snippets
+  snippet = {
+    expand = function(args)
+        vim.fn["vsnip#anonymous"](args.body)
+    end,
+  },
+  mapping = {
+    ['<C-p>'] = cmp.mapping.select_prev_item(),
+    ['<C-n>'] = cmp.mapping.select_next_item(),
+    -- Add tab support
+    ['<S-Tab>'] = cmp.mapping.select_prev_item(),
+    ['<Tab>'] = cmp.mapping.select_next_item(),
+    ['<C-S-f>'] = cmp.mapping.scroll_docs(-4),
+    ['<C-f>'] = cmp.mapping.scroll_docs(4),
+    ['<C-Space>'] = cmp.mapping.complete(),
+    ['<C-e>'] = cmp.mapping.close(),
+    ['<CR>'] = cmp.mapping.confirm({
+      behavior = cmp.ConfirmBehavior.Insert,
+      select = true,
+    })
+  },
+  -- Installed sources:
+  sources = {
+    { name = 'path' },                              -- file paths
+    { name = 'nvim_lsp', keyword_length = 3 },      -- from language server
+    { name = 'nvim_lsp_signature_help'},            -- display function signatures with current parameter emphasized
+    { name = 'nvim_lua', keyword_length = 2},       -- complete neovim's Lua runtime API such vim.lsp.*
+    { name = 'buffer', keyword_length = 2 },        -- source current buffer
+    { name = 'vsnip', keyword_length = 2 },         -- nvim-cmp source for vim-vsnip 
+    { name = 'calc'},                               -- source for math calculation
+  },
+  window = {
+      completion = cmp.config.window.bordered(),
+      documentation = cmp.config.window.bordered(),
+  },
+  formatting = {
+      fields = {'menu', 'abbr', 'kind'},
+      format = function(entry, item)
+          local menu_icon ={
+              nvim_lsp = 'λ',
+              vsnip = '⋗',
+              buffer = 'Ω',
+              path = '🖫',
+          }
+          item.menu = menu_icon[entry.source.name]
+          return item
+      end,
+  },
+})
+
 -- set terminal title
 function _G.current_tab()
   local curr_buf = vim.fn.bufnr()

vim.nix

@@ -8,6 +8,16 @@
     plugins = with pkgs.vimPlugins; [
       vim-nix
       rust-vim
+      rust-tools-nvim
+      nvim-cmp
+      snippets-nvim
+      nvim-treesitter
+      nvim-treesitter-parsers.rust
+      nvim-treesitter-parsers.lua
+      nvim-treesitter-parsers.toml
+      mason-nvim
+      mason-tool-installer-nvim
+      mason-lspconfig-nvim
       fzf-vim
       sleuth
       whitespace-nvim # ,t to trim whitespace