Postal code validation has been added into the library.

Author: jmosawy

index.js

@@ -1,7 +1,9 @@
 const Phone = require('./phone');
+const Postal = require('./postal');
 
 const Verifier = function () {};
 
 Verifier.prototype.Phone = Phone;
+Verifier.prototype.Postal = Postal;
 
 module.exports = new Verifier();

postal/index.js

@@ -0,0 +1,14 @@
+const PostalCodeRegex = /^[13-9]{10}$/;
+
+const Postal = function () {};
+
+/**
+ * Check if the entered postal code is valid.
+ * @param {string} postalCode
+ * @returns {boolean}
+ */
+Postal.prototype.isPostalCodeValid = function (postalCode) {
+  return new RegExp(PostalCodeRegex).test(postalCode);
+};
+
+module.exports = new Postal();

test/postal-test.js

@@ -0,0 +1,18 @@
+const { describe, it } = require('mocha');
+const { expect } = require('chai');
+const { Postal } = require('../index');
+
+describe('Postal Tools', () => {
+  describe('isPostalCodeValid', () => {
+    it('should be valid postal codes', () => {
+      expect(Postal.isPostalCodeValid('1834556784')).to.equal(true);
+      expect(Postal.isPostalCodeValid('7634598734')).to.equal(true);
+      expect(Postal.isPostalCodeValid('3813187764')).to.equal(true);
+    });
+    it('should be not a valid postal code', () => {
+      expect(Postal.isPostalCodeValid('76654543')).to.equal(false);
+      expect(Postal.isPostalCodeValid('1898875423')).to.equal(false);
+      expect(Postal.isPostalCodeValid('1890875413')).to.equal(false);
+    });
+  });
+});