fix: add compatability with [email protected] streams

fixes mafintosh#6

index.js

@@ -16,6 +16,20 @@ var destroyer = function(self, end) {
   }
 }
 
+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 end = function(ws, fn) {
   if (!ws) return fn()
   if (ws._writableState && ws._writableState.finished) return fn()
@@ -166,8 +180,7 @@ 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

@@ -301,10 +301,14 @@ tape('close is bubbled up on both ends - destroy on listener', function(t) {
 tape('close is bubbled up on both ends - destroy on dialer', function(t) {
   var listener
   var counter = 0
-
+  t.plan(2)
   listener = tcp.createServer(function(socket) {
     var dup = duplexify(socket, socket)
 
+    dup.once('data', function(chunk) {
+      t.same(chunk, Buffer('hello world'))
+    })
+
     socket.on('close', count)
     dup.on('close', count)
   })
@@ -314,6 +318,8 @@ tape('close is bubbled up on both ends - destroy on dialer', function(t) {
   var socket = tcp.connect(listener.address())
   var dup = duplexify(socket, socket)
 
+  dup.write(Buffer('hello world'))
+
   socket.on('close', count)
   dup.on('close', count)
 
@@ -323,7 +329,9 @@ tape('close is bubbled up on both ends - destroy on dialer', function(t) {
 
   function count() {
     if (++counter === 4) {
-      return listener.close(t.end)
+      return listener.close(function() {
+        t.ok(true)
+      })
     }
   }
 })