--update: code for palindrome

Author: ashokdey

src/palindrome/index.js

@@ -0,0 +1,23 @@
+function palindromeUsingLoop(str) {
+  let isPalindrome = true;
+  let j = str.length - 1;
+
+  for (let i = 0; i < str.length / 2; i += 1) {
+    if (str[i] !== str[j]) {
+      isPalindrome = false;
+      break;
+    }
+    j -= 1;
+  }
+
+  return isPalindrome;
+}
+
+function palindromeUsingEvery(str) {
+  return str.split('').every((char, index) => char === str[str.length - 1 - index]);
+}
+
+module.exports = {
+  palindromeUsingLoop,
+  palindromeUsingEvery,
+};

src/palindrome/palindrome.test.js

@@ -0,0 +1,31 @@
+const { palindromeUsingLoop, palindromeUsingEvery } = require('.');
+
+describe('Palindrome Strings', () => {
+  let mirror;
+  let madam;
+
+  beforeEach(() => {
+    mirror = 'mirror';
+    madam = 'madam';
+  });
+
+  describe('Using traditional loop', () => {
+    it('Should return FALSE for `mirror`', () => {
+      expect(palindromeUsingLoop(mirror)).toBe(false);
+    });
+
+    it('Should return TRUE for `madam`', () => {
+      expect(palindromeUsingLoop(madam)).toBe(true);
+    });
+  });
+
+  describe('Using ES6 Array.every', () => {
+    it('Should return FALSE for `mirror`', () => {
+      expect(palindromeUsingEvery(mirror)).toBe(false);
+    });
+
+    it('Should return TRUE for `madam`', () => {
+      expect(palindromeUsingEvery(madam)).toBe(true);
+    });
+  });
+});