fix: add compatability with node@6.3.0 streams

Fixes #6

index.js

@@ -24,6 +24,19 @@ var end = function(ws, fn) {
   fn()
 }
 
+var getStateLength = function(state) {
+  if (state.buffer.length) {
+    // Since node 6.3.0 state.buffer is a BufferList not an array
+    if (state.buffer.head) {
+      return state.buffer.head.data.length
+    }
+
+    return state.buffer[0].length
+  }
+
+  return state.length
+}
+
 var toStreams2 = function(rs) {
   return new (stream.Readable)({objectMode:true, highWaterMark:16}).wrap(rs)
 }
@@ -158,7 +171,7 @@ Duplexify.prototype._forward = function() {
   var data
   var state = this._readable2._readableState
 
-  while ((data = this._readable2.read(state.buffer.length ? state.buffer[0].length : state.length)) !== null) {
+  while ((data = this._readable2.read(getStateLength(state))) !== null) {
     this._drained = this.push(data)
   }
 

test.js

@@ -1,6 +1,7 @@
 var tape = require('tape')
 var through = require('through2')
 var concat = require('concat-stream')
+var tcp = require('net')
 var duplexify = require('./')
 
 tape('passthrough', function(t) {
@@ -266,4 +267,27 @@ tape('close', function(t) {
     t.ok(true, 'should forward close')
     t.end()
   })
-})
+})
+
+tape('works with node native streams (tcp)', function(t) {
+  var socket
+  t.plan(1)
+
+  var listener = tcp.createServer(function(socket) {
+    var dup = duplexify(socket, socket)
+
+    dup.once('data', function(chunk) {
+      t.same(chunk, Buffer('hello world'))
+      listener.close()
+      socket.end()
+      t.end()
+    })
+  })
+
+  listener.listen(0)
+
+  socket = tcp.connect(listener.address())
+  var dup = duplexify(socket, socket)
+
+  dup.write(Buffer('hello world'))
+})