Merge pull request #436 from aladin002dz/AddPhoneNumberFormatting

Add Phone Number Formatting Function

Author: pomkarnath98

String/FormatPhoneNumber.js

@@ -0,0 +1,17 @@
+// function that takes 10 digits and returns a string of the formatted phone number
+// e.g.: 1234567890 -> (123) 456-7890
+
+const formatPhoneNumber = (numbers) => {
+ const numbersString = numbers.toString()
+ if ((numbersString.length !== 10) || isNaN(numbersString)) {
+ // return "Invalid phone number."
+ throw new TypeError('Invalid phone number.')
+ }
+ const arr = '(XXX) XXX-XXXX'.split('')
+ Array.from(numbersString).forEach(n => {
+ arr[arr.indexOf('X')] = n
+ })
+ return arr.join('')
+}
+
+export { formatPhoneNumber }

String/FormatPhoneNumber.test.js

@@ -0,0 +1,23 @@
+import { formatPhoneNumber } from './FormatPhoneNumber'
+
+describe('PhoneNumberFormatting', () => {
+ it('expects to return the formatted phone number', () => {
+ expect(formatPhoneNumber('1234567890')).toEqual('(123) 456-7890')
+ })
+
+ it('expects to return the formatted phone number', () => {
+ expect(formatPhoneNumber(1234567890)).toEqual('(123) 456-7890')
+ })
+
+ it('expects to throw a type error', () => {
+ expect(() => { formatPhoneNumber('1234567') }).toThrow('Invalid phone number.')
+ })
+
+ it('expects to throw a type error', () => {
+ expect(() => { formatPhoneNumber('123456text') }).toThrow('Invalid phone number.')
+ })
+
+ it('expects to throw a type error', () => {
+ expect(() => { formatPhoneNumber(12345) }).toThrow('Invalid phone number.')
+ })
+})