From 80668fff1a037a30ace5a2427ed43d57b06df5f1 Mon Sep 17 00:00:00 2001
From: Vasco Santos <vasco.santos@moxy.studio>
Date: Wed, 15 Jul 2020 11:21:34 +0200
Subject: [PATCH] feat: arrayEquals for non primitive types with equals
 function

---
 src/array-equals.js       | 14 ++++++++
 test/array-equals.spec.js | 76 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 90 insertions(+)
 create mode 100644 src/array-equals.js
 create mode 100644 test/array-equals.spec.js

diff --git a/src/array-equals.js b/src/array-equals.js
new file mode 100644
index 0000000..e293167
--- /dev/null
+++ b/src/array-equals.js
@@ -0,0 +1,14 @@
+'use strict'
+
+/**
+ * Verify if two arrays of non primitive types with the "equals" function are equal.
+ * Compatible with multiaddr, peer-id and Buffer.
+ * @param {Array<*>} a
+ * @param {Array<*>} b
+ * @returns {boolean}
+ */
+function arrayEquals (a, b) {
+  return a.length === b.length && b.sort() && a.sort().every((item, index) => b[index].equals(item))
+}
+
+module.exports = arrayEquals
diff --git a/test/array-equals.spec.js b/test/array-equals.spec.js
new file mode 100644
index 0000000..36c60cc
--- /dev/null
+++ b/test/array-equals.spec.js
@@ -0,0 +1,76 @@
+/* eslint-env mocha */
+'use strict'
+
+const chai = require('chai')
+const dirtyChai = require('dirty-chai')
+const expect = chai.expect
+chai.use(dirtyChai)
+
+const multiaddr = require('multiaddr')
+
+const arrayEquals = require('../src/array-equals')
+
+describe('non primitive array equals', () => {
+  it('returns true if two arrays of multiaddrs are equal', () => {
+    const a = [
+      multiaddr('/ip4/127.0.0.1/tcp/8000'),
+      multiaddr('/ip4/127.0.0.1/tcp/3000/ws'),
+      multiaddr('/dns4/test.libp2p.io')
+    ]
+
+    const b = [
+      multiaddr('/ip4/127.0.0.1/tcp/8000'),
+      multiaddr('/ip4/127.0.0.1/tcp/3000/ws'),
+      multiaddr('/dns4/test.libp2p.io')
+    ]
+
+    expect(arrayEquals(a, b)).to.eql(true)
+  })
+
+  it('returns true if two arrays of multiaddrs have the same content but different orders', () => {
+    const a = [
+      multiaddr('/ip4/127.0.0.1/tcp/8000'),
+      multiaddr('/ip4/127.0.0.1/tcp/3000/ws'),
+      multiaddr('/dns4/test.libp2p.io')
+    ]
+
+    const b = [
+      multiaddr('/ip4/127.0.0.1/tcp/3000/ws'),
+      multiaddr('/ip4/127.0.0.1/tcp/8000'),
+      multiaddr('/dns4/test.libp2p.io')
+    ]
+
+    expect(arrayEquals(a, b)).to.eql(true)
+  })
+
+  it('returns false if two arrays of multiaddrs are different', () => {
+    const a = [
+      multiaddr('/ip4/127.0.0.1/tcp/8000'),
+      multiaddr('/ip4/127.0.0.1/tcp/3000/ws'),
+      multiaddr('/dns4/test.libp2p.io')
+    ]
+
+    const b = [
+      multiaddr('/ip4/127.0.0.1/tcp/8001'),
+      multiaddr('/ip4/127.0.0.1/tcp/3000/ws'),
+      multiaddr('/dns4/test.libp2p.io')
+    ]
+
+    expect(arrayEquals(a, b)).to.eql(false)
+  })
+
+  it('returns false if two arrays of multiaddrs are partially equal, but different lengths', () => {
+    const a = [
+      multiaddr('/ip4/127.0.0.1/tcp/8000'),
+      multiaddr('/ip4/127.0.0.1/tcp/3000/ws'),
+      multiaddr('/dns4/test.libp2p.io')
+    ]
+
+    const b = [
+      multiaddr('/ip4/127.0.0.1/tcp/8001'),
+      multiaddr('/dns4/test.libp2p.io')
+    ]
+
+    expect(arrayEquals(a, b)).to.eql(false)
+  })
+})