fix(dial): proper error handling on dial (#77)

package.json

@@ -48,6 +48,7 @@
     "lodash.isfunction": "^3.0.8",
     "mafmt": "^2.1.6",
     "multiaddr": "^2.2.2",
+    "once": "^1.4.0",
     "stream-to-pull-stream": "^1.7.2"
   },
   "contributors": [

src/index.js

@@ -6,6 +6,7 @@ const mafmt = require('mafmt')
 const includes = require('lodash.includes')
 const isFunction = require('lodash.isfunction')
 const Connection = require('interface-connection').Connection
+const once = require('once')
 const debug = require('debug')
 const log = debug('libp2p:tcp:dial')
 
@@ -22,16 +23,24 @@ module.exports = class TCP {
       cb = () => {}
     }
 
+    cb = once(cb)
     const cOpts = ma.toOptions()
     log('Connecting to %s %s', cOpts.port, cOpts.host)
 
-    const rawSocket = net.connect(cOpts, cb)
-
+    const rawSocket = net.connect(cOpts)
     rawSocket.once('timeout', () => {
       log('timeout')
       rawSocket.emit('error', new Error('Timeout'))
     })
 
+    rawSocket.once('error', cb)
+
+    rawSocket.once('connect', () => {
+      rawSocket.removeListener('error', cb)
+      cb()
+    })
+
+
     const socket = toPull.duplex(rawSocket)
 
     const conn = new Connection(socket)

test/index.spec.js

@@ -471,6 +471,13 @@ describe('Connection wrap', () => {
     )
   })
 
+  it('dial error', (done) => {
+    tcp.dial(multiaddr('/ip4/999.0.0.1/tcp/1234'), (err) => {
+      expect(err).to.exist()
+      done()
+    })
+  })
+
   it('matryoshka wrap', (done) => {
     const conn = tcp.dial(ma)
     const connWrap1 = new Connection(conn)