From 9a3e74cefad84a71a776bf960a109bfaf06be12f Mon Sep 17 00:00:00 2001
From: Angelos Chalaris <chalarangelo@gmail.com>
Date: Sun, 5 Jan 2020 21:40:39 +0200
Subject: [PATCH] Add haveSameContents snippet

---
 snippets/haveSameContents.md  | 23 +++++++++++++++++++++++
 test/haveSameContents.test.js | 17 +++++++++++++++++
 2 files changed, 40 insertions(+)
 create mode 100644 snippets/haveSameContents.md
 create mode 100644 test/haveSameContents.test.js

diff --git a/snippets/haveSameContents.md b/snippets/haveSameContents.md
new file mode 100644
index 000000000..4168dd7aa
--- /dev/null
+++ b/snippets/haveSameContents.md
@@ -0,0 +1,23 @@
+---
+title: haveSameContents
+tags: array,intermediate
+---
+
+Returns `true` if two arrays contain the same elements regardless of order, `false` otherwise.
+
+Use a `for...of` loop over a `Set` created from the values of both arrays.
+Use `Array.prototype.filter()` to compare the amount of occurences of each distinct value in both arrays.
+Return `false` if the counts do not match for any element, `true` otherwise.
+
+```js
+const haveSameContents = (a, b) => {
+  for (const v of new Set([...a, ...b]))
+    if (a.filter(e => e === v).length !== b.filter(e => e === v).length)
+      return false;
+  return true;
+}
+```
+
+```js
+haveSameContents([1, 2, 4], [2, 4, 1]); // true
+```
diff --git a/test/haveSameContents.test.js b/test/haveSameContents.test.js
new file mode 100644
index 000000000..fd6632a45
--- /dev/null
+++ b/test/haveSameContents.test.js
@@ -0,0 +1,17 @@
+const {haveSameContents} = require('./_30s.js');
+
+test('haveSameContents is a Function', () => {
+  expect(haveSameContents).toBeInstanceOf(Function);
+});
+test('returns true for arrays with same contents', () => {
+  expect(haveSameContents([1, 2, 3], [2, 3, 1])).toBeTruthy();
+});
+test('returns false for arrays with different contents', () => {
+  expect(haveSameContents([1, 2], [2, 3, 1])).toBeFalsy();
+});
+test('returns false for arrays with different contents', () => {
+  expect(haveSameContents([1, 2, 3], [2, 1])).toBeFalsy();
+});
+test('returns false for arrays with different contents', () => {
+  expect(haveSameContents([1, 2, 3], [2, 1, 6])).toBeFalsy();
+});