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PatrickMcSweeny's solution

to Phone Number in the JavaScript Track

Published at Aug 24 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.

Setup

Go through the setup instructions for Javascript to install the necessary dependencies:

https://exercism.io/tracks/javascript/installation

Requirements

Install assignment dependencies:

$ npm install

Making the test suite pass

Execute the tests with:

$ npm test

In the test suites all tests but the first have been skipped.

Once you get a test passing, you can enable the next one by changing xtest to test.

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.spec.js

import { PhoneNumber } from './phone-number';

describe('PhoneNumber()', () => {
  test('cleans the number', () => {
    const phone = new PhoneNumber('(223) 456-7890');
    expect(phone.number()).toEqual('2234567890');
  });

  xtest('cleans numbers with dots', () => {
    const phone = new PhoneNumber('223.456.7890');
    expect(phone.number()).toEqual('2234567890');
  });

  xtest('cleans numbers with multiple spaces', () => {
    const phone = new PhoneNumber('223 456   7890   ');
    expect(phone.number()).toEqual('2234567890');
  });

  xtest('invalid when 9 digits', () => {
    const phone = new PhoneNumber('223456789');
    expect(phone.number()).toEqual(null);
  });

  xtest('invalid when 11 digits does not start with a 1', () => {
    const phone = new PhoneNumber('22234567890');
    expect(phone.number()).toEqual(null);
  });

  xtest('valid when 11 digits and starting with 1', () => {
    const phone = new PhoneNumber('12234567890');
    expect(phone.number()).toEqual('2234567890');
  });

  xtest('valid when 11 digits and starting with 1 even with punctuation', () => {
    const phone = new PhoneNumber('+1 (223) 456-7890');
    expect(phone.number()).toEqual('2234567890');
  });

  xtest('invalid when 12 digits', () => {
    const phone = new PhoneNumber('322234567890');
    expect(phone.number()).toEqual(null);
  });

  xtest('invalid with letters', () => {
    const phone = new PhoneNumber('223-abc-7890');
    expect(phone.number()).toEqual(null);
  });

  xtest('invalid with punctuations', () => {
    const phone = new PhoneNumber('223-@:!-7890');
    expect(phone.number()).toEqual(null);
  });

  xtest('invalid if area code starts with 0 or 1', () => {
    const phone1 = new PhoneNumber('(023) 456-7890');
    const phone2 = new PhoneNumber('(123) 456-7890');
    expect(phone1.number()).toEqual(null);
    expect(phone2.number()).toEqual(null);
  });

  xtest('invalid if exchange code starts with 0 or 1', () => {
    const phone1 = new PhoneNumber('(223) 056-7890');
    const phone2 = new PhoneNumber('(223) 156-7890');
    expect(phone1.number()).toEqual(null);
    expect(phone2.number()).toEqual(null);
  });

  xtest('invalid when 11 digits starting with 1, '
  + 'but invalid area/exchange code first digits', () => {
    const phone1 = new PhoneNumber('1 (023) 456-7890');
    const phone2 = new PhoneNumber('1 (123) 456-7890');
    const phone3 = new PhoneNumber('1 (223) 056-7890');
    const phone4 = new PhoneNumber('1 (223) 156-7890');
    expect(phone1.number()).toEqual(null);
    expect(phone2.number()).toEqual(null);
    expect(phone3.number()).toEqual(null);
    expect(phone4.number()).toEqual(null);
  });
});
export class PhoneNumber {
  constructor(input) {
    input = input.replace(/\D/g, "");

    if(input[0] === "1"){
      input = input.slice(1);
    }

    this.phoneNumber = input;
  }

  number() {
    if(this.isValid()){
      return this.phoneNumber;
    }else{
      return null;
    }
  }

  isValid() {
    return this.validLength() && this.validFirstNumber();
  }

  validLength() {
    return this.phoneNumber.length === 10;
  }

  validFirstNumber() {
    return parseInt(this.phoneNumber[0]) > 1 && parseInt(this.phoneNumber[3]) > 1;
  }
}

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