extensive playing with LSP setup

nix/home.nix

@@ -48,7 +48,8 @@ let
     };
   };
 
-in {
+in
+{
   home.packages = with pkgs; [
     git-plan
     htop
@@ -148,7 +149,8 @@ in {
 
       vim-commentary
       vim-airline
-      { plugin = rainbow;
+      {
+        plugin = rainbow;
         config = ''
           let g:rainbow_conf = {
           \ 'guifgs': ['RoyalBlue3', 'SeaGreen3', 'DarkOrchid3', 'firebrick3', 'RoyalBlue3', 'SeaGreen3', 'DarkOrchid3', 'firebrick3', 'RoyalBlue3', 'DarkOrchid3', 'firebrick3', 'RoyalBlue3', 'SeaGreen3', 'DarkOrchid3', 'firebrick3'],
@@ -162,7 +164,8 @@ let g:rainbow_active = 1
       vim-indent-guides
       vim-surround
       fugitive
-      { plugin = easymotion;
+      {
+        plugin = easymotion;
         config = ''
           map / <Plug>(easymotion-sn)
           omap / <Plug>(easymotion-tn)
@@ -173,7 +176,8 @@ let g:EasyMotion_landing_highlight = 0
       }
       vinegar
       undotree
-      { plugin = vim-test;
+      {
+        plugin = vim-test;
         config = ''
           nmap <silent> <leader>t :TestNearest<CR>
           nmap <silent> <leader>T :TestFile<CR>
@@ -183,27 +187,25 @@ nmap <silent> <leader>g :TestVisit<CR>
           let test#strategy = "neovim"
         '';
       }
-      { plugin = ale;
+      {
+        plugin = ale;
         config = ''
           let g:ale_fix_on_save = 1
           let g:ale_elixir_credo_strict = 1
           let g:ale_fixers = {
-  \ 'elm': ['elm-format', 'format'],
             \ 'javascript': ['prettier'],
             \ 'javascript.jsx': ['prettier'],
             \ 'javascriptreact': ['prettier'],
-  \ 'typescriptreact': ['prettier'],
-  \ 'typescript': ['prettier'],
             \ 'ruby': ['sorbet'],
             \ 'rust': ['rustfmt'],
-  \ 'elixir': ['mix_format']
             \}
           let g:ale_linters_explicit = 1
         '';
       }
       fzf-vim
       fzfWrapper
-      { plugin = nvim-compe;
+      {
+        plugin = nvim-compe;
         config = ''
           set completeopt=menuone,noselect
           let g:compe = {}
@@ -234,14 +236,19 @@ let g:compe.source.emoji = v:true
         '';
       }
       vim-goyo
-      { plugin = nvim-lspconfig ;
+      {
+        plugin = nvim-lspconfig;
         config = ''
           lua << EOF
-          require'lspconfig'.elmls.setup{}
+          ${readFile (
-          require'lspconfig'.tsserver.setup{}
+          pkgs.substituteAll {
-          require'lspconfig'.elixirls.setup{
+            src = ./vim/nvim-lspconfig.lua;
-            cmd = { "${pkgs.elixir_ls}/bin/elixir-ls" };
+            # since both of these are used for actually configuring the system,
+            # we'll probably always want them around.
+            lua_ls = pkgs.sumneko-lua-language-server;
+            rnix_lsp = pkgs.rnix-lsp;
           }
+        ) }
           EOF
         '';
       }

nix/vim/nvim-lspconfig.lua

@@ -0,0 +1,91 @@
+local nvim_lsp = require("lspconfig")
+
+local format_async = function(err, _, result, _, bufnr)
+    if err ~= nil or result == nil then return end
+    if not vim.api.nvim_buf_get_option(bufnr, "modified") then
+        local view = vim.fn.winsaveview()
+        vim.lsp.util.apply_text_edits(result, bufnr)
+        vim.fn.winrestview(view)
+        if bufnr == vim.api.nvim_get_current_buf() then
+            vim.api.nvim_command("noautocmd :update")
+        end
+    end
+end
+vim.lsp.handlers["textDocument/formatting"] = format_async
+
+local on_attach = function(client, bufnr)
+    local buf_map = vim.api.nvim_buf_set_keymap
+
+    vim.cmd("command! LspDef lua vim.lsp.buf.definition()")
+    vim.cmd("command! LspFormatting lua vim.lsp.buf.formatting()")
+    vim.cmd("command! LspCodeAction lua vim.lsp.buf.code_action()")
+    vim.cmd("command! LspHover lua vim.lsp.buf.hover()")
+    vim.cmd("command! LspRename lua vim.lsp.buf.rename()")
+    vim.cmd("command! LspOrganize lua lsp_organize_imports()")
+    vim.cmd("command! LspRefs lua vim.lsp.buf.references()")
+    vim.cmd("command! LspTypeDef lua vim.lsp.buf.type_definition()")
+    vim.cmd("command! LspImplementation lua vim.lsp.buf.implementation()")
+    vim.cmd("command! LspDiagPrev lua vim.lsp.diagnostic.goto_prev()")
+    vim.cmd("command! LspDiagNext lua vim.lsp.diagnostic.goto_next()")
+    vim.cmd("command! LspDiagLine lua vim.lsp.diagnostic.show_line_diagnostics()")
+    vim.cmd("command! LspSignatureHelp lua vim.lsp.buf.signature_help()")
+
+    buf_map(bufnr, "n", "gd", ":LspDef<CR>", {silent = true})
+    buf_map(bufnr, "n", "gr", ":LspRename<CR>", {silent = true})
+    buf_map(bufnr, "n", "gR", ":LspRefs<CR>", {silent = true})
+    buf_map(bufnr, "n", "gy", ":LspTypeDef<CR>", {silent = true})
+    buf_map(bufnr, "n", "K", ":LspHover<CR>", {silent = true})
+    buf_map(bufnr, "n", "gs", ":LspOrganize<CR>", {silent = true})
+    buf_map(bufnr, "n", "[a", ":LspDiagPrev<CR>", {silent = true})
+    buf_map(bufnr, "n", "]a", ":LspDiagNext<CR>", {silent = true})
+    buf_map(bufnr, "n", "ga", ":LspCodeAction<CR>", {silent = true})
+    buf_map(bufnr, "n", "<Leader>a", ":LspDiagLine<CR>", {silent = true})
+    buf_map(bufnr, "i", "<C-x><C-x>", "<cmd> LspSignatureHelp<CR>", {silent = true})
+
+    if client.resolved_capabilities.document_formatting then
+        vim.api.nvim_exec([[
+         augroup LspAutocommands
+             autocmd! * <buffer>
+             autocmd BufWritePost <buffer> LspFormatting
+         augroup END
+         ]], true)
+    end
+end
+
+nvim_lsp.diagnosticls.setup {
+    on_attach = on_attach
+}
+
+nvim_lsp.elmls.setup{
+  on_attach = on_attach;
+}
+nvim_lsp.tsserver.setup {
+    on_attach = function(client)
+        -- Avoid conflict with prettier
+        client.resolved_capabilities.document_formatting = false
+        on_attach(client)
+    end
+}
+nvim_lsp.elixirls.setup{
+  cmd = { "elixir-ls" };
+  on_attach = on_attach;
+}
+nvim_lsp.rnix.setup{
+  cmd = { "@rnix_lsp@/bin/rnix-lsp" };
+  on_attach = on_attach;
+}
+nvim_lsp.rust_analyzer.setup{
+  on_attach = on_attach;
+}
+
+nvim_lsp.sumneko_lua.setup{
+  cmd = { "@lua_ls@/bin/lua-language-server" };
+  on_attach = on_attach;
+  settings = {
+    Lua = {
+      diagnostics = {
+          globals = { 'vim' }
+      }
+    }
+  };
+}