dotfiles/config/nvim/lua/lsp.lua

local lsp_installer = require("nvim-lsp-installer")
local cmp = require("cmp")
local configs = require("lspconfig/configs")
local nvim_lsp = require("lspconfig")

local kind_icons = {
    Text = "",
    Method = "",
    Function = "",
    Constructor = "",
    Field = "",
    Variable = "",
    Class = "ﴯ",
    Interface = "",
    Module = "",
    Property = "ﰠ",
    Unit = "",
    Value = "",
    Enum = "",
    Keyword = "",
    Snippet = "",
    Color = "",
    File = "",
    Reference = "",
    Folder = "",
    EnumMember = "",
    Constant = "",
    Struct = "",
    Event = "",
    Operator = "",
    TypeParameter = ""
}

cmp.setup({
    snippet = {
        expand = function(args) require("luasnip").lsp_expand(args.body) end
    },
    mapping = {
        ["<C-j>"] = cmp.mapping.select_next_item({
            behavior = cmp.SelectBehavior.Select
        }),
        ["<C-k>"] = cmp.mapping.select_prev_item({
            behavior = cmp.SelectBehavior.Select
        }),
        ["<C-space>"] = cmp.mapping.complete(),
        ["<CR>"] = cmp.mapping.confirm({
            select = true,
            behavior = cmp.SelectBehavior.Insert
        }),
        ["<TAB>"] = cmp.mapping.confirm({
            select = true,
            behavior = cmp.SelectBehavior.Insert
        })
    },
    sources = cmp.config.sources({
        {name = "nvim_lsp", trigger_characters = {".", "!", "#", ">", "*"}},
        {name = "luasnip"}, {name = "nvim_lua"}
    }, {{name = "path"}, {name = "buffer"}}),
    completion = {completeopt = "menu,menuone,noselect,noinsert,preview"},
    experimental = {ghost_text = true},
    sorting = {
        comparators = {cmp.config.compare.sort_text, cmp.config.compare.kind}
    },
    documentation = {
        border = {"╭", "─", "╮", "│", "╯", "─", "╰", "│"},
        zindex = 999
    },
    formatting = {
        format = function(entry, vim_item)
            vim_item.kind = string.format('%s %s', kind_icons[vim_item.kind],
                                          vim_item.kind)
            vim_item.menu = ({
                buffer = "[Buffer]",
                luasnip = "[Snippet]",
                nvim_lua = "[Lua]",
                path = "[File]"
            })[entry.source.name]
            return vim_item
        end
    }
})

vim.cmd([[
highlight! CmpItemAbbrDeprecated guibg=NONE gui=strikethrough guifg=#808080
]])

cmp.setup.cmdline("/", {sources = {{name = "buffer"}}})

cmp.setup.cmdline(":", {sources = {{name = "path"}, {name = "cmdline"}}})

local capabilities = require('cmp_nvim_lsp').update_capabilities(vim.lsp
                                                                     .protocol
                                                                     .make_client_capabilities())
capabilities.textDocument.completion.completionItem.snippetSupport = true

local function setupLspSignature()
    require("lsp_signature").setup({
        bind = true,
        hint_enable = false,
        handler_opts = {border = "rounded"}
    })
end

lsp_installer.on_server_ready(function(server)
    local opts = {capabilities = capabilities}

    if server.name == "sumneko_lua" then
        local runtime_path = vim.split(package.path, ';')
        table.insert(runtime_path, "lua/?.lua")
        table.insert(runtime_path, "lua/?/init.lua")

        opts.settings = {
            Lua = {
                runtime = {version = "LuaJIT", path = runtime_path},
                diagnostics = {globals = {"vim"}},
                workspace = {library = vim.api.nvim_get_runtime_file("", true)},
                telemetry = {enable = false}
            }
        }
    end

    setupLspSignature()

    server:setup(opts)
end)

-- Use this emmet lsp - https://github.com/pedro757/emmet
configs.ls_emmet = {
    default_config = {
        cmd = {'ls_emmet', '--stdio'},
        filetypes = {
            'html', 'css', 'scss', 'javascriptreact', 'typescriptreact', 'haml',
            'xml', 'xsl', 'pug', 'slim', 'sass', 'stylus', 'less', 'sss'
        },
        root_dir = function(fname) return vim.loop.cwd() end,
        settings = {}
    }
}
nvim_lsp.ls_emmet.setup({capabilities = capabilities})

nvim_lsp.gopls.setup({
    capabilities = capabilities,
    on_attach = function() setupLspSignature() end,
    settings = {
      gopls = {
        experimentalPostfixCompletions = true,
        analyses = {
          unusedparams = true,
          shadow = true
        },
        staticcheck = true
      }
    }
})

function goimports(timeout_ms)
  local context = { only = { "source.organizeImports" } }
  vim.validate { context = { context, "t", true } }

  local params = vim.lsp.util.make_range_params()
  params.context = context

  -- See the implementation of the textDocument/codeAction callback
  -- (lua/vim/lsp/handler.lua) for how to do this properly.
  local result = vim.lsp.buf_request_sync(0, "textDocument/codeAction", params, timeout_ms)
  if not result or next(result) == nil then return end
  local actions = result[1].result
  if not actions then return end
  local action = actions[1]

  -- textDocument/codeAction can return either Command[] or CodeAction[]. If it
  -- is a CodeAction, it can have either an edit, a command or both. Edits
  -- should be executed first.
  if action.edit or type(action.command) == "table" then
    if action.edit then
      vim.lsp.util.apply_workspace_edit(action.edit)
    end
    if type(action.command) == "table" then
      vim.lsp.buf.execute_command(action.command)
    end
  else
    vim.lsp.buf.execute_command(action)
  end
end

vim.cmd([[autocmd BufWritePre *.go lua vim.lsp.buf.formatting_sync()]])
vim.cmd([[autocmd BufWritePre *.go lua goimports(1000)]])

require("luasnip/loaders/from_vscode").load({
    include = {"javascript", "typescript", "go", "html"}
})