fix: validate list (#97)

package.json

@@ -29,7 +29,8 @@
   },
   "devDependencies": {
     "aegir": "^20.4.1",
-    "chai": "^4.2.0"
+    "chai": "^4.2.0",
+    "dirty-chai": "^2.0.1"
   },
   "dependencies": {
     "debug": "^4.1.1",

src/index.js

@@ -1,10 +1,11 @@
 'use strict'
 
+const assert = require('assert')
 const PeerId = require('peer-id')
 const PeerInfo = require('peer-info')
 const multiaddr = require('multiaddr')
 const mafmt = require('mafmt')
-const EventEmitter = require('events').EventEmitter
+const { EventEmitter } = require('events')
 const debug = require('debug')
 
 const log = debug('libp2p:bootstrap')
@@ -19,11 +20,13 @@ class Bootstrap extends EventEmitter {
    *
    * @param {Object} options
    * @param {Array<string>} options.list - the list of peer addresses in multi-address format
-   * @param {number} options.interval - the interval between emitting addresses (in milli-seconds)
+   * @param {number} [options.interval] - the interval between emitting addresses in milliseconds (default: 10000)
    *
    */
-  constructor (options) {
+  constructor (options = {}) {
+    assert(options.list && options.list.length, 'Bootstrap requires a list of peer addresses')
     super()
+
     this._list = options.list
     this._interval = options.interval || 10000
     this._timer = null

test/bootstrap.spec.js

@@ -1,13 +1,26 @@
-/* eslint-env mocha */
 'use strict'
+/* eslint-env mocha */
+
+const chai = require('chai')
+chai.use(require('dirty-chai'))
+const { expect } = chai
 
 const Bootstrap = require('../src')
 const peerList = require('./default-peers')
 const partialValidPeerList = require('./some-invalid-peers')
-const { expect } = require('chai')
 const mafmt = require('mafmt')
 
 describe('bootstrap', () => {
+  it('should throw if no peer list is provided', () => {
+    try {
+      const b = new Bootstrap() // eslint-disable-line no-unused-vars
+    } catch (err) {
+      expect(err).to.exist()
+      return
+    }
+    throw new Error('should throw if no peer list is provided')
+  })
+
   it('find the other peer', function () {
     this.timeout(5 * 1000)
     const r = new Bootstrap({