Use PrintDiagnostics with highlight in nvim-lspconfig

PrintDiagnostics.lua

local hl_tbl = {
   [vim.diagnostic.severity.ERROR] = "DiagnosticError",
   [vim.diagnostic.severity.WARN] = "DiagnosticWarn",
   [vim.diagnostic.severity.HINT] = "DiagnosticHint",
   [vim.diagnostic.severity.INFO] = "DiagnosticInfo",
}

function PrintDiagnostics(opts, bufnr, line_nr, client_id)
  bufnr = bufnr or 0
  line_nr = line_nr or (vim.api.nvim_win_get_cursor(0)[1] - 1)
  opts = opts or {['lnum'] = line_nr}

  local line_diagnostics = vim.diagnostic.get(bufnr, opts)
  if vim.tbl_isempty(line_diagnostics) then return end

  local diagnostic_message = ""
  local hl = "Normal"
  for i, diagnostic in ipairs(line_diagnostics) do
    diagnostic_message = diagnostic_message .. string.format("%d: %s", i, diagnostic.message or "")
    if i ~= #line_diagnostics then
      diagnostic_message = diagnostic_message .. "\n"
    end
    hl=hl_tbl[diagnostic.severity]
  end
  vim.api.nvim_echo({{diagnostic_message, hl}}, false, {})
end

vim.cmd [[ autocmd! CursorHold * lua PrintDiagnostics() ]]