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
Event Manager by JumpstartLab http://tutorials.jumpstartlab.com/projects/eventmanager.html
It's possible to submit an incomplete solution so you can see how others have completed the exercise.
require 'minitest/autorun'
require_relative 'phone_number'
# Common test data version: 1.6.0 a317aa4
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
def self.clean(input)
new(input).valid_number
end
def initialize(input)
@phone_number = input
end
def valid_number
remove_nondigits
remove_leading_one
phone_number if valid?
end
private
attr_reader :phone_number
def valid?
phone_number.length == 10 && area_code_valid? && exchange_code_valid?
end
def area_code_valid?
phone_number[0].match?(/[2-9]/)
end
def exchange_code_valid?
phone_number[3].match?(/[2-9]/)
end
def remove_nondigits
@phone_number.gsub!(/\D/, '')
end
def remove_leading_one
@phone_number.gsub!(/^1/, '')
end
end
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