add tests to check for the close event

index.js

@@ -46,6 +46,7 @@ var Duplexify = function(writable, readable, opts) {
   this._unread = null
   this._ended = false
 
+  this.closed = false
   this.destroyed = false
 
   if (writable) this.setWritable(writable)
@@ -130,6 +131,13 @@ Duplexify.prototype.setReadable = function(readable) {
     self.push(null)
   }
 
+  var onclose = function() {
+    if (!self.closed) {
+      self.closed = true
+      self.emit('close')
+    }
+  }
+
   var clear = function() {
     self._readable2.removeListener('readable', onreadable)
     self._readable2.removeListener('end', onend)
@@ -141,6 +149,7 @@ Duplexify.prototype.setReadable = function(readable) {
   this._readable2 = readable._readableState ? readable : toStreams2(readable)
   this._readable2.on('readable', onreadable)
   this._readable2.on('end', onend)
+  this._readable2.on('close', onclose)
   this._unread = clear
 
   this._forward()
@@ -188,7 +197,10 @@ Duplexify.prototype._destroy = function(err) {
     if (this._writable && this._writable.destroy) this._writable.destroy()
   }
 
-  this.emit('close')
+  if (!this.closed) {
+    this.closed = true
+    this.emit('close')
+  }
 }
 
 Duplexify.prototype._write = function(data, enc, cb) {

test.js

@@ -2,6 +2,7 @@ var tape = require('tape')
 var through = require('through2')
 var concat = require('concat-stream')
 var duplexify = require('./')
+var tcp = require('net')
 
 tape('passthrough', function(t) {
   t.plan(2)
@@ -261,9 +262,68 @@ tape('close', function(t) {
   var dup = duplexify(passthrough, passthrough)
   var ok = false
 
-  passthrough.emit('close')
   dup.on('close', function() {
     t.ok(true, 'should forward close')
     t.end()
   })
-})
+
+  passthrough.emit('close')
+})
+
+tape('close is bubbled up on both ends - destroy on listener', function(t) {
+  var listener
+  var counter = 0
+
+  listener = tcp.createServer(function(socket) {
+    var dup = duplexify(socket, socket)
+
+    socket.on('close', count)
+    dup.on('close', count)
+
+    dup.destroy()
+  })
+
+  listener.listen(0)
+
+  var socket = tcp.connect(listener.address())
+  var dup = duplexify(socket, socket)
+
+  socket.on('close', count)
+  dup.on('close', count)
+
+  function count() {
+    if (++counter === 4) {
+      return listener.close(t.end)
+    }
+  }
+})
+
+tape('close is bubbled up on both ends - destroy on dialer', function(t) {
+  var listener
+  var counter = 0
+
+  listener = tcp.createServer(function(socket) {
+    var dup = duplexify(socket, socket)
+
+    socket.on('close', count)
+    dup.on('close', count)
+  })
+
+  listener.listen(0)
+
+  var socket = tcp.connect(listener.address())
+  var dup = duplexify(socket, socket)
+
+  socket.on('close', count)
+  dup.on('close', count)
+
+  setTimeout(function () {
+    dup.destroy()
+  }, 100)
+
+  function count() {
+    if (++counter === 4) {
+      return listener.close(t.end)
+    }
+  }
+})