CSV::Writer#quote

# File tmp/rubies/ruby-3.3.0/lib/csv/writer.rb, line 190
def quote(field, i)
  if @force_quotes
    quote_field(field)
  elsif @force_quotes_fields and @force_quotes_fields[i]
    quote_field(field)
  else
    if field.nil?  # represent +nil+ fields as empty unquoted fields
      ""
    else
      field = String(field)  # Stringify fields
      # represent empty fields as empty quoted fields
      if (@quote_empty and field.empty?) or (field.valid_encoding? and @quotable_pattern.match?(field))
        quote_field(field)
      else
        field  # unquoted field
      end
    end
  end
end