extensive playing with LSP setup

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' }
+      }
+    }
+  };
+}