Drag my neovim config kicking and screaming into the future (LSP)

3 files changed, 125 insertions, 85 deletions

diff --git a/nvim/default.nix b/nvim/default.nix
index 87a4693..4e108f0 100644
--- a/nvim/default.nix
+++ b/nvim/default.nix
@@ -2,69 +2,54 @@
 
   pkgs = (import ../pkgs.nix).stable {};
 
-  misspell = pkgs.buildGoPackage rec {
-    pname = "misspell";
-    version = "0.3.4";
-    goPackagePath = "github.com/client9/misspell";
-
-    src = pkgs.fetchFromGitHub {
-      owner = "client9";
-      repo = "misspell";
-      rev = "v${version}";
-      sha256 = "1vwf33wsc4la25zk9nylpbp9px3svlmldkm0bha4hp56jws4q9cs";
-    };
-
-    goDeps = ./misspellDeps.nix;
+  gopls = pkgs.buildGoModule rec {
+    pname = "gopls";
+    version = "0.16.2";
+
+    src = "${pkgs.fetchFromGitHub {
+      owner = "golang";
+      repo = "tools";
+      rev = "gopls/v${version}";
+      sha256 = "sha256-amy00VMUcmyjDoZ4d9/+YswfcZ+1/cGvFsA4sAmc1dA=";
+    }}/gopls";
+
+    subPackages = ["."];
+    vendorHash = "sha256-ta94xPboFtSxFeuMtPX76XiC1O7osNl4oLk64wIyyz4=";
+    doCheck = false;
   };
 
   env = pkgs.buildEnv {
     name = "nvim-env";
     paths = [
-      pkgs.shellcheck
-      misspell
+      gopls
     ];
   };
 
-  envPlugins = "${env}/share/vim-plugins";
+  init = pkgs.writeText "nvim-init.lua" ''
+    vim.cmd('source ${pkgs.vimPlugins.vim-plug}/plug.vim')
 
-  init = pkgs.writeText "nvim-init" ''
-    source ${pkgs.vimPlugins.vim-plug}/plug.vim
+    local Plug = vim.fn['plug#']
 
-    call plug#begin()
-    Plug '${pkgs.vimPlugins.deoplete-nvim}'
-    Plug '${pkgs.vimPlugins.nerdtree}', { 'on':  'NERDTreeToggle' }
-    Plug '${pkgs.vimPlugins.nerdtree-git-plugin}'
-    Plug '${pkgs.vimPlugins.vim-gitgutter}'
-    Plug '${pkgs.vimPlugins.neomake}'
-    Plug '${pkgs.vimPlugins.vim-go}', { 'for': 'go' }
-    Plug '${pkgs.vimPlugins.vim-nix}', { 'for': 'nix' }
-    Plug '${pkgs.vimPlugins.rust-vim}', { 'for': 'rust' }
-    call plug#end()
+    vim.call('plug#begin')
 
-    source ${./init.vim}
-  '';
+    Plug('${pkgs.vimPlugins.nerdtree}', { ['on'] = 'NERDTreeToggle' })
+    Plug('${pkgs.vimPlugins.nerdtree-git-plugin}')
+    Plug('${pkgs.vimPlugins.vim-gitgutter}')
 
-  nvimRaw = pkgs.writeScriptBin "nvim" ''
-    #!${pkgs.bash}/bin/bash
-    export PATH=${env}/bin:$PATH
-    exec ${pkgs.neovim}/bin/nvim -u ${init} "$@"
-  '';
+    Plug('${pkgs.vimPlugins.nvim-lspconfig}')
+    Plug('${pkgs.vimPlugins.nvim-cmp}')
+    Plug('${pkgs.vimPlugins.cmp-nvim-lsp}')
 
-  rplugin = pkgs.stdenv.mkDerivation {
-    name = "nvim-rplugin";
-    buildInputs = [ pkgs.git pkgs.tree nvimRaw ];
-    builder = builtins.toFile "builder.sh" ''
-      source $stdenv/setup
-      mkdir -p "$out"/
-      export NVIM_RPLUGIN_MANIFEST="$out"/rplugin.vim
-      nvim -i NONE -c ':UpdateRemotePlugins' -c ':exit' >/dev/null
-    '';
-  };
+    vim.call('plug#end')
+
+    vim.cmd('source ${./init.vim}')
+
+    ${builtins.readFile ./init.lua}
+  '';
 
   nvim = pkgs.writeScriptBin "nvim" ''
     #!${pkgs.bash}/bin/bash
-    export NVIM_RPLUGIN_MANIFEST=${rplugin}/rplugin.vim
-    exec ${nvimRaw}/bin/nvim "$@"
+    export PATH=${env}/bin:$PATH
+    exec ${pkgs.neovim}/bin/nvim -u ${init} "$@"
   '';
-
 }
diff --git a/nvim/init.lua b/nvim/init.lua
new file mode 100644
index 0000000..9f4e393
--- /dev/null
+++ b/nvim/init.lua
@@ -0,0 +1,91 @@
+--------------------------------------------------------------------------------
+-- LSP configuration. nvim-cmp related stuff taken from:
+-- https://github.com/neovim/nvim-lspconfig/wiki/Autocompletion/217feffc675a17d8ab95259ed9d4c6d62e1cd2e1
+--------------------------------------------------------------------------------
+
+local lspconfig = require("lspconfig")
+
+local capabilities = require("cmp_nvim_lsp").default_capabilities()
+
+-- https://github.com/hrsh7th/nvim-cmp/issues/373#issuecomment-1434284568
+capabilities.textDocument.completion.completionItem.snippetSupport = false
+
+lspconfig.gopls.setup {
+    capabilities = capabilities,
+}
+
+local cmp = require("cmp")
+cmp.setup {
+  mapping = cmp.mapping.preset.insert({
+    ['<C-u>'] = cmp.mapping.scroll_docs(-4), -- Up
+    ['<C-d>'] = cmp.mapping.scroll_docs(4), -- Down
+    -- C-b (back) C-f (forward) for snippet placeholder navigation.
+    ['<C-Space>'] = cmp.mapping.complete(),
+    ['<CR>'] = cmp.mapping.confirm {
+      behavior = cmp.ConfirmBehavior.Replace,
+      select = true,
+    },
+    ['<Tab>'] = cmp.mapping(function(fallback)
+      if cmp.visible() then
+        cmp.select_next_item()
+      else
+        fallback()
+      end
+    end, { 'i', 's' }),
+    ['<S-Tab>'] = cmp.mapping(function(fallback)
+      if cmp.visible() then
+        cmp.select_prev_item()
+      else
+        fallback()
+      end
+    end, { 'i', 's' }),
+  }),
+  sources = {
+    { name = 'nvim_lsp' },
+  },
+}
+
+-- Format files using LSP on save
+vim.api.nvim_create_autocmd('BufWritePre', {
+  callback = function(args)
+    vim.lsp.buf.format()
+  end,
+})
+
+-- Open LSP Diagnostics in quickfix list on save
+vim.api.nvim_create_autocmd('BufWritePost', {
+  callback = function(args)
+    vim.diagnostic.setqflist()
+  end,
+})
+
+--------------------------------------------------------------------------------
+-- Run 'organizeImports' on save for go files. Apparently organizing imports is
+-- considered a separate task than formatting, so it's implemented separately
+-- (in a much more cumbersome way, for some reason).
+-- https://github.com/golang/tools/blob/0b989c812dcb662451db0b70a8267fe7e211886e/gopls/doc/vim.md#neovim-imports
+-- https://github.com/golang/go/issues/33587
+--------------------------------------------------------------------------------
+
+vim.api.nvim_create_autocmd("BufWritePre", {
+  pattern = "*.go",
+  callback = function()
+    local params = vim.lsp.util.make_range_params()
+    params.context = {only = {"source.organizeImports"}}
+    -- buf_request_sync defaults to a 1000ms timeout. Depending on your
+    -- machine and codebase, you may want longer. Add an additional
+    -- argument after params if you find that you have to write the file
+    -- twice for changes to be saved.
+    -- E.g., vim.lsp.buf_request_sync(0, "textDocument/codeAction", params, 3000)
+    local result = vim.lsp.buf_request_sync(0, "textDocument/codeAction", params)
+    for cid, res in pairs(result or {}) do
+      for _, r in pairs(res.result or {}) do
+        if r.edit then
+          local enc = (vim.lsp.get_client_by_id(cid) or {}).offset_encoding or "utf-16"
+          vim.lsp.util.apply_workspace_edit(r.edit, enc)
+        end
+      end
+    end
+    vim.lsp.buf.format({async = false})
+  end
+})
diff --git a/nvim/init.vim b/nvim/init.vim
index 08ce5eb..213099f 100644
--- a/nvim/init.vim
+++ b/nvim/init.vim
@@ -1,16 +1,6 @@
 
 set noswapfile
 
-" Deoplete #################################################################
-
-let g:deoplete#enable_at_startup = 1
-" use tab to cycle
-inoremap <expr><tab> pumvisible() ? "\<c-n>" : "\<tab>"
-" close preview when leaving insert
-autocmd InsertLeave,CompleteDone * if pumvisible() == 0 | pclose | endif
-" use omni completion for go, provided by vim-go
-call deoplete#custom#option('omni_patterns', { 'go': '[^. *\t]\.\w*' })
-
 " NERDTree #################################################################
 
 let NERDTreeMouseMode=3
@@ -34,39 +24,13 @@ map <C-n> :NERDTreeToggle<CR>
 " always enter term buffer in insert mode
 autocmd BufEnter * if &buftype == 'terminal' | :startinsert | endif
 
-" vim-go ###################################################################
-
-let g:go_fmt_autosave = 1
-let g:go_fmt_command="goimports"
-
 " rust.vim ###################################################################
 
 let g:rustfmt_autosave = 1
 
 " Caddyfile ####################################################################
-"
-au BufNewFile,BufRead Caddyfile,*.Caddyfile,Caddyfile.* set ft=caddyfile
-
-" neomake ##################################################################
 
-autocmd! BufWritePost * Neomake
-"let g:neomake_verbose=3
-"let g:neomake_logfile='/tmp/neomake.log'
-
-" Always run clippy on rust projects
-autocmd! BufWritePost *.rs Neomake! clippy
-
-" the sidebar sign placement wasn't playing nice with gitgutter, so use the
-" location list instead. But location list is kinda dumb cause it pops open
-" multiple times and at weird times, sooo.... fuck it
-"let g:neomake_open_list=2
-let g:neomake_open_list=0
-let g:neomake_place_signs=0
-
-let g:neomake_markdown_enabled_makers = ['misspell']
-let g:neomake_markdown_misspell_maker = {
-    \ 'errorformat': '%f:%l:%c:%m',
-    \ }
+au BufNewFile,BufRead Caddyfile,*.Caddyfile,Caddyfile.* set ft=caddyfile
 
 " mine #####################################################################