feat: feature: isEqual. Adds the isEqual function. All tests passing … (#7)

* feat: feature: isEqual. Adds the isEqual function. All tests passing | Fix: Small bug fix in tests

issue #4

* feat: feature: isEqual. Adds the isEqual function. All tests passing | Fix: Small bug fix in tests

issue #4

* start of new changes

* small change

* figured it out

* updated readme

Co-authored-by: John McDonald <[email protected]>

Author: petesamper

README.md

@@ -30,6 +30,7 @@ This is a tiny library of javascript functions, currently comprising:
 - sieveOfE (sieve of Eratosthenes)
 - peek
 - sort
-- isEqual (in progress)
+- isEqual
 - inPlaceShuffle
 - regularShuffle
+

src/index.js

@@ -1,10 +1,11 @@
-export { default as flatten } from "./flatten.js";
-export { default as deepCopy } from "./deepCopy.js";
-export { default as isPrime } from "./isPrime.js";
-export { default as peek } from "./peek.js";
-export { default as sieveOfE } from "./sieveOfE.js";
-export { default as sort } from "./sort.js";
-export { default as camelCase } from "./camelCase.js";
+export { default as flatten } from './flatten.js';
+export { default as deepCopy } from './deepCopy.js';
+export { default as isPrime } from './isPrime.js';
+export { default as peek } from './peek.js';
+export { default as sieveOfE } from './sieveOfE.js';
+export { default as sort } from './sort.js';
+export { default as camelCase } from './camelCase.js';
+export { default as isEqual } from './isEqual';
 export { default as inPlaceShuffle } from "./inPlaceShuffle.js";
 export { default as regularShuffle } from "./regularShuffle.js";
 export { default as randomInteger } from "./randomInteger.js";

src/isEqual.js

@@ -1 +1,76 @@
-// in progress
+/**
+ * compares two objects or arrays
+ * @param {Array or Object} a - The Array or Object to compare
+ * @param {Array or Object} b - The Array or Object to compare
+ * @return {boolean}
+ */
+
+// Helper returns a value's internal object [[Class]];
+const getClass = (obj) => {
+  return Object.prototype.toString.call(obj);
+};
+
+const isEqual = (a, b) => {
+  // Assumes that both params will be of the same data structure type.
+  // If arrays:
+  if (Array.isArray(a)) {
+    for (let i = 0; i <= a.length; i++) {
+      if (a[i] !== b[i]) {
+        return false;
+      } else {
+        return true;
+      }
+    }
+    // If objects:
+  } else {
+    // If a and b reference the same value, return true:
+    if (a === b) return true;
+
+    // If a and b are !both Objects, return false:
+    if (typeof a != typeof b) return false;
+
+    // If type is number:
+    // TODO
+
+    // Get internal [[class]]:
+    const aClass = getClass(a);
+    const bClass = getClass(b);
+    // If classes are different, return false:
+    if (aClass != bClass) return false;
+
+    // If String, Number, or Boolean objects:
+    if (
+      aClass == '[object Boolean]' ||
+      aClass == '[object String]' ||
+      aClass == '[object Error]'
+    ) {
+      if (a.toString() != b.toString()) return false;
+    }
+
+    // Grab the keys:
+    const aKeys = Object.keys(a);
+    const bKeys = Object.keys(b);
+
+    // if !same # of keys, return false:
+    if (aKeys.length !== bKeys.length) {
+      return false;
+    }
+
+    // Check if they have the same keys:
+    if (
+      !aKeys.every((key) => {
+        return b.hasOwnProperty(key);
+      })
+    ) {
+      return false;
+    }
+
+    // Check key values - recursion:
+    return aKeys.every((key) => {
+      return isEqual(a[key], b[key]);
+    });
+  }
+  return false;
+};
+
+module.exports = isEqual;

src/tests/isEqual.test.js

@@ -1,18 +1,18 @@
-const expect = require("chai").expect;
-const isEqual = require("../").isEqual;
+const expect = require('chai').expect;
+const isEqual = require('../').isEqual;
 
-describe("isEqual", () => {
-  xit("compares two objects and returns true if they have identical keys and values", () => {
-    const objOne = { name: { first: "John" } };
-    const objTwo = { name: { first: "John" } };
+describe('isEqual', () => {
+  it('compares two objects and returns true if they have identical keys and values', () => {
+    const objOne = { name: { first: 'John' } };
+    const objTwo = { name: { first: 'John' } };
     expect(isEqual(objOne, objTwo)).to.equal(true);
   });
-  xit("compares two objects and returns false if they have non-identical keys and values", () => {
-    const objOne = { name: { first: "John" } };
-    const objTwo = { name: { first: "Pete" } };
+  it('compares two objects and returns false if they have non-identical keys and values', () => {
+    const objOne = { name: { first: 'John' } };
+    const objTwo = { name: { first: 'Pete' } };
     expect(isEqual(objOne, objTwo)).to.equal(false);
   });
-  xit("compares two arrays and returns true is they have identical values", () => {
+  it('compares two arrays and returns true is they have identical values', () => {
     const arrOne = [1, [2, [3]]];
     const arrTwo = [1, [2, [3]]];
     expect(isEqual(arrOne, arrTwo)).to.equal(true);