CSV::Parser#parse_quoted_column_value

# File tmp/rubies/ruby-3.1.3/lib/csv/parser.rb, line 1150
def parse_quoted_column_value
  quotes = @scanner.scan_all(@quotes)
  return nil unless quotes

  @quoted_column_value = true
  n_quotes = quotes.size
  if (n_quotes % 2).zero?
    quotes[0, (n_quotes - 2) / 2]
  else
    value = quotes[0, n_quotes / 2]
    while true
      quoted_value = @scanner.scan_all(@quoted_value)
      value << quoted_value if quoted_value
      if @backslash_quote
        if @scanner.scan(@escaped_backslash)
          if @scanner.scan(@escaped_quote)
            value << @quote_character
          else
            value << @backslash_character
          end
          next
        end
      end

      quotes = @scanner.scan_all(@quotes)
      unless quotes
        ignore_broken_line
        message = "Unclosed quoted field"
        raise MalformedCSVError.new(message, @lineno)
      end
      n_quotes = quotes.size
      if n_quotes == 1
        break
      else
        value << quotes[0, n_quotes / 2]
        break if (n_quotes % 2) == 1
      end
    end
    value
  end
end