Parse CSV file for colons or semicolons

csv_with_semicolons_or_colons_parser.rb

# CSV.parse(csv_header, col_sep: ColSepSniffer.find(csv_header))
# returns a CSV::Table object
p CSV.parse(csv_file,
          headers: true,
          col_sep: ColSepSniffer.find(csv_headers)).map(&:to_hash)
#!/usr/bin/env ruby
# encoding: utf-8

require "csv"

class ColSepSniffer
  NoColumnSeparatorFound = Class.new(StandardError)
  EmptyString = Class.new(StandardError)

  COMMON_DELIMITERS = [
    '","',
    '";"'
  ].freeze

  def initialize(string)
    @string = string
  end

  def self.find(string)
    new(string).find
  end

  def find
    fail EmptyString unless @string

    if valid?
      delimiters[0][0][1]
    else
      fail NoColumnSeparatorFound
    end
  end

  private

  def valid?
    !delimiters.collect(&:last).reduce(:+).zero?
  end

  def delimiters
    @delimiters ||= COMMON_DELIMITERS.inject({}, &count).sort(&most_found)
  end

  def most_found
    ->(a, b) { b[1] <=> a[1] }
  end

  def count
    ->(hash, delimiter) { hash[delimiter] = @string.count(delimiter); hash }
  end
end

csv_file = "ID;Name;Country\n1;Perico;España\n2;Björn;Germany\n"
csv_headers = csv_file.lines.first
# CSV.parse(csv_header, col_sep: ColSepSniffer.find(csv_header))
# returns a CSV::Table object
p CSV.parse(csv_file,
          headers: true,
          col_sep: ColSepSniffer.find(csv_headers)).map(&:to_h)
# => [{"ID"=>"1", "Name"=>"Perico", "Country"=>"España"},
#     {"ID"=>"2", "Name"=>"Björn", "Country"=>"Germany"}]

I've got errror unterminated string meets end of file

This script have 5 years not sure if it works with the new ruby versions