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w1zeman1p's solution

to Phone Number in the Ruby Track

Published at Feb 07 2019 · 0 comments
Instructions
Test suite
Solution

Clean up user-entered phone numbers so that they can be sent SMS messages.

The North American Numbering Plan (NANP) is a telephone numbering system used by many countries in North America like the United States, Canada or Bermuda. All NANP-countries share the same international country code: 1.

NANP numbers are ten-digit numbers consisting of a three-digit Numbering Plan Area code, commonly known as area code, followed by a seven-digit local number. The first three digits of the local number represent the exchange code, followed by the unique four-digit number which is the subscriber number.

The format is usually represented as

(NXX)-NXX-XXXX

where N is any digit from 2 through 9 and X is any digit from 0 through 9.

Your task is to clean up differently formatted telephone numbers by removing punctuation and the country code (1) if present.

For example, the inputs

  • +1 (613)-995-0253
  • 613-995-0253
  • 1 613 995 0253
  • 613.995.0253

should all produce the output

6139950253

Note: As this exercise only deals with telephone numbers used in NANP-countries, only 1 is considered a valid country code.


For installation and learning resources, refer to the Ruby resources page.

For running the tests provided, you will need the Minitest gem. Open a terminal window and run the following command to install minitest:

gem install minitest

If you would like color output, you can require 'minitest/pride' in the test file, or note the alternative instruction, below, for running the test file.

Run the tests from the exercise directory using the following command:

ruby phone_number_test.rb

To include color from the command line:

ruby -r minitest/pride phone_number_test.rb

Source

Event Manager by JumpstartLab http://tutorials.jumpstartlab.com/projects/eventmanager.html

Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.

phone_number_test.rb

require 'minitest/autorun'
require_relative 'phone_number'

# Common test data version: 1.6.1 fc57696
class PhoneNumberTest < Minitest::Test
  def test_cleans_the_number
    # skip
    assert_equal "2234567890", PhoneNumber.clean("(223) 456-7890")
  end

  def test_cleans_numbers_with_dots
    skip
    assert_equal "2234567890", PhoneNumber.clean("223.456.7890")
  end

  def test_cleans_numbers_with_multiple_spaces
    skip
    assert_equal "2234567890", PhoneNumber.clean("223 456   7890   ")
  end

  def test_invalid_when_9_digits
    skip
    assert_nil PhoneNumber.clean("123456789")
  end

  def test_invalid_when_11_digits_does_not_start_with_a_1
    skip
    assert_nil PhoneNumber.clean("22234567890")
  end

  def test_valid_when_11_digits_and_starting_with_1
    skip
    assert_equal "2234567890", PhoneNumber.clean("12234567890")
  end

  def test_valid_when_11_digits_and_starting_with_1_even_with_punctuation
    skip
    assert_equal "2234567890", PhoneNumber.clean("+1 (223) 456-7890")
  end

  def test_invalid_when_more_than_11_digits
    skip
    assert_nil PhoneNumber.clean("321234567890")
  end

  def test_invalid_with_letters
    skip
    assert_nil PhoneNumber.clean("123-abc-7890")
  end

  def test_invalid_with_punctuations
    skip
    assert_nil PhoneNumber.clean("123-@:!-7890")
  end

  def test_invalid_if_area_code_starts_with_0
    skip
    assert_nil PhoneNumber.clean("(023) 456-7890")
  end

  def test_invalid_if_area_code_starts_with_1
    skip
    assert_nil PhoneNumber.clean("(123) 456-7890")
  end

  def test_invalid_if_exchange_code_starts_with_0
    skip
    assert_nil PhoneNumber.clean("(223) 056-7890")
  end

  def test_invalid_if_exchange_code_starts_with_1
    skip
    assert_nil PhoneNumber.clean("(223) 156-7890")
  end

  def test_invalid_if_area_code_starts_with_0_on_valid_11_digit_number
    skip
    assert_nil PhoneNumber.clean("1 (023) 456-7890")
  end

  def test_invalid_if_area_code_starts_with_1_on_valid_11_digit_number
    skip
    assert_nil PhoneNumber.clean("1 (123) 456-7890")
  end

  def test_invalid_if_exchange_code_starts_with_0_on_valid_11_digit_number
    skip
    assert_nil PhoneNumber.clean("1 (223) 056-7890")
  end

  def test_invalid_if_exchange_code_starts_with_1_on_valid_11_digit_number
    skip
    assert_nil PhoneNumber.clean("1 (223) 156-7890")
  end
end
class PhoneNumber
  attr_reader :digits

  def self.clean(input)
    PhoneNumber.new(input).to_s
  end

  def initialize(input)
    @digits = as_digits(input)
  end

  def to_s(sep="")
    if valid?
      "#{area_code}#{sep}#{exchange_code}#{sep}#{subscriber_number}"
    end
  end

  def length
    digits.length
  end

  def valid?
    return false if country_code != 1
    return false if !length.between?(10, 11)
    return false if !exchange_code_digits[0].between?(2, 9)
    return false if !area_code_digits[0].between?(2, 9)
    true
  end

  def country_code
    length == 11 ? digits[0] : 1
  end

  def area_code
    area_code_digits.join
  end

  def exchange_code
    exchange_code_digits.join
  end

  def subscriber_number
    subscriber_number_digits.join
  end

  private

  def as_digits(input)
    input.scan(/\d/).map(&:to_i)
  end

  def area_code_digits
    digits[-10..-8]
  end

  def exchange_code_digits
    digits[-7..-5]
  end

  def subscriber_number_digits
    digits[-4..-1]
  end
end

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