jdhao-nvim-config/lua/config/lsp.lua

local M = {}

function M.show_line_diagnostics()
  local opts = {
    focusable = false,
    close_events = {'BufLeave', 'CursorMoved', 'InsertEnter', 'FocusLost'}
  }
  vim.lsp.diagnostic.show_line_diagnostics(opts)
end

local custom_attach = function(client, bufnr)
  local function buf_set_keymap(...) vim.api.nvim_buf_set_keymap(bufnr, ...) end
  local function buf_set_option(...) vim.api.nvim_buf_set_option(bufnr, ...) end

  buf_set_option('omnifunc', 'v:lua.vim.lsp.omnifunc')

  -- Mappings.
  local opts = { noremap=true, silent=true }
  buf_set_keymap('n', 'gD', '<Cmd>lua vim.lsp.buf.declaration()<CR>', opts)
  buf_set_keymap('n', 'gd', '<Cmd>lua vim.lsp.buf.definition()<CR>', opts)
  buf_set_keymap('n', '<C-]>', '<Cmd>lua vim.lsp.buf.definition()<CR>', opts)
  buf_set_keymap('n', 'K', '<Cmd>lua vim.lsp.buf.hover()<CR>', opts)
  buf_set_keymap('n', 'gi', '<cmd>lua vim.lsp.buf.implementation()<CR>', opts)
  buf_set_keymap('n', '<C-k>', '<cmd>lua vim.lsp.buf.signature_help()<CR>', opts)
  buf_set_keymap('n', '<space>wa', '<cmd>lua vim.lsp.buf.add_workspace_folder()<CR>', opts)
  buf_set_keymap('n', '<space>wr', '<cmd>lua vim.lsp.buf.remove_workspace_folder()<CR>', opts)
  buf_set_keymap('n', '<space>wl', '<cmd>lua print(vim.inspect(vim.lsp.buf.list_workspace_folders()))<CR>', opts)
  buf_set_keymap('n', '<space>D', '<cmd>lua vim.lsp.buf.type_definition()<CR>', opts)
  buf_set_keymap('n', '<space>rn', '<cmd>lua vim.lsp.buf.rename()<CR>', opts)
  buf_set_keymap('n', 'gr', '<cmd>lua vim.lsp.buf.references()<CR>', opts)
  buf_set_keymap('n', '[d', '<cmd>lua vim.lsp.diagnostic.goto_prev()<CR>', opts)
  buf_set_keymap('n', ']d', '<cmd>lua vim.lsp.diagnostic.goto_next()<CR>', opts)
  buf_set_keymap('n', '<space>q', '<cmd>lua vim.lsp.diagnostic.set_loclist()<CR>', opts)
  buf_set_keymap('n', '<space>ca', '<cmd>lua vim.lsp.buf.code_action()<CR>', opts)

  vim.cmd [[
    autocmd CursorHold <buffer> lua require('config.lsp').show_line_diagnostics()
  ]]

  -- Set some key bindings conditional on server capabilities
  if client.resolved_capabilities.document_formatting then
    buf_set_keymap("n", "<space>f", "<cmd>lua vim.lsp.buf.formatting()<CR>", opts)
  end
  if client.resolved_capabilities.document_range_formatting then
    buf_set_keymap("x", "<space>f", "<cmd>lua vim.lsp.buf.range_formatting()<CR><ESC>", opts)
  end

  -- The blow command will highlight the current variable and its usages in the buffer.
  if client.resolved_capabilities.document_highlight then
    vim.cmd([[
      hi link LspReferenceRead Visual
      hi link LspReferenceText Visual
      hi link LspReferenceWrite Visual
      augroup lsp_document_highlight
        autocmd! * <buffer>
        autocmd CursorHold <buffer> lua vim.lsp.buf.document_highlight()
        autocmd CursorMoved <buffer> lua vim.lsp.buf.clear_references()
      augroup END
    ]])
  end

  local msg = string.format('Language server %s started!' , client.name)
  vim.api.nvim_echo({{msg, 'MoreMsg'}, }, false, {})
end

local capabilities = vim.lsp.protocol.make_client_capabilities()
capabilities.textDocument.completion.completionItem.snippetSupport = true

local lspconfig = require("lspconfig")

lspconfig.pylsp.setup{
  on_attach = custom_attach,
  settings = {
    pylsp = {
      plugins = {
        pylint = {enabled = true, executable = "pylint"},
        pyflakes = {enabled = false},
        pycodestyle = {enabled = false},
        jedi_completion = {fuzzy = true},
        pyls_isort = {enabled = true},
        pylsp_mypy = {enabled = true}
      }
    }
  },
  flags = {
    debounce_text_changes = 200,
  }
}

-- lspconfig.pyright.setup{
--   on_attach = custom_attach,
-- }

lspconfig.clangd.setup{
  on_attach = custom_attach,
  capabilities = capabilities,
  filetypes = { "c", "cpp", "cc" },
  flags = {
    debounce_text_changes = 500,
  }
}

-- set up vim-language-server
lspconfig.vimls.setup{
  on_attach = custom_attach,
  flags = {
    debounce_text_changes = 500,
  }
}

local sumneko_binary_path = vim.fn.exepath('lua-language-server')
if vim.g.is_mac or vim.g.is_linux and sumneko_binary_path ~= '' then
  local sumneko_root_path = vim.fn.fnamemodify(sumneko_binary_path, ':h:h:h')

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

  require'lspconfig'.sumneko_lua.setup {
    on_attach = custom_attach,
    cmd = {sumneko_binary_path, "-E", sumneko_root_path .. "/main.lua"};
    settings = {
      Lua = {
        runtime = {
          -- Tell the language server which version of Lua you're using (most likely LuaJIT in the case of Neovim)
          version = 'LuaJIT',
          -- Setup your lua path
          path = runtime_path,
        },
        diagnostics = {
          -- Get the language server to recognize the `vim` global
          globals = {'vim'},
        },
        workspace = {
          -- Make the server aware of Neovim runtime files
          library = vim.api.nvim_get_runtime_file("", true),
        },
        -- Do not send telemetry data containing a randomized but unique identifier
        telemetry = {
          enable = false,
        },
      },
    },
  }
end

-- Change diagnostic signs.
vim.fn.sign_define('LspDiagnosticsSignError', { text = "✗", texthl = "LspDiagnosticsDefaultError" })
vim.fn.sign_define('LspDiagnosticsSignWarning', { text = "!", texthl = "LspDiagnosticsDefaultWarning" })
vim.fn.sign_define('LspDiagnosticsSignInformation', { text = "", texthl = "LspDiagnosticsDefaultInformation" })
vim.fn.sign_define('LspDiagnosticsSignHint', { text = "", texthl = "LspDiagnosticsDefaultHint" })

vim.lsp.handlers["textDocument/publishDiagnostics"] = vim.lsp.with(
  vim.lsp.diagnostic.on_publish_diagnostics, {
    underline = false,
    virtual_text = false,
    signs = true,
    update_in_insert = false,
  }
)

-- Refs: https://github.com/neovim/nvim-lspconfig/wiki/UI-customization#show-source-in-diagnostics
vim.lsp.handlers["textDocument/publishDiagnostics"] =
  function(_, _, params, client_id, _)
    local uri = params.uri
    local bufnr = vim.uri_to_bufnr(uri)

    if not bufnr then
      return
    end

    if not vim.api.nvim_buf_is_loaded(bufnr) then
      return
    end

    local diagnostics = params.diagnostics
    for i, v in ipairs(diagnostics) do
      diagnostics[i].message = string.format("%s: %s", v.source, v.message)
    end
    vim.lsp.diagnostic.save(diagnostics, bufnr, client_id)

    local config = {
      underline = false,
      virtual_text = false,
      signs = true,
      update_in_insert = false,
    }
    vim.lsp.diagnostic.display(diagnostics, bufnr, client_id, config)
  end

-- The following settings works with the bleeding edge neovim.
-- See https://github.com/neovim/neovim/pull/13998.
vim.lsp.handlers["textDocument/hover"] = vim.lsp.with(
  vim.lsp.handlers.hover, {
    border = 'rounded'
  }
)

return M