HTTP outgoing queue bug fix (#2639)

lib/_http_outgoing.js

@@ -51,7 +51,8 @@ function OutgoingMessage() {
   this.outputCallbacks = [];
 
   this.writable = true;
-
+  this.explicitfinish = false;
+
   this._last = false;
   this.chunkedEncoding = false;
   this.shouldKeepAlive = true;
@@ -133,8 +134,12 @@ OutgoingMessage.prototype._writeRaw = function(data, encoding, callback) {
     encoding = null;
   }
 
+  //if this happens and callback is finish - it will be fired in bad time!!!  
+  assert(!(this.connection && data.length === 0 && this.output.length > 0));
+
   if (data.length === 0) {
-    if (typeof callback === 'function')
+    //callback cannot be called (finish) when the connection is not assigned
+    if (typeof callback === 'function' && this.connection)
       process.nextTick(callback);
     return true;
   }
@@ -536,7 +541,9 @@ OutgoingMessage.prototype.end = function(data, encoding, callback) {
 
   var self = this;
   function finish() {
-    self.emit('finish');
+	//finish MUST NOT be called when connection is not assigned
+	assert(self.connection);
+	self.emit('finish');
   }
 
   if (typeof callback === 'function')
@@ -574,6 +581,12 @@ OutgoingMessage.prototype.end = function(data, encoding, callback) {
   } else {
     // Force a flush, HACK.
     ret = this._send('', 'binary', finish);
+    if (!this.connection) {
+    	//if there is nothing to send and connection is not assigned, nothing is put into output buffer, so no callback will be called after write
+    	//and nexttick callback in _writeraw MUST be skipped - so finish must be explicitly called after flushing this message as it becomes the first in queue
+    	//this should be really rewritten
+    	this.explicitfinish = true;
+    }
   }
 
   if (this.connection && data)
@@ -587,14 +600,14 @@ OutgoingMessage.prototype.end = function(data, encoding, callback) {
   if (this.output.length === 0 &&
       this.connection &&
       this.connection._httpMessage === this) {
-    this._finish();
+    this.prefinish();
   }
 
   return ret;
 };
 
 
-OutgoingMessage.prototype._finish = function() {
+OutgoingMessage.prototype.prefinish = function() {
   assert(this.connection);
   this.emit('prefinish');
 };
@@ -642,7 +655,14 @@ OutgoingMessage.prototype._flush = function() {
 
     if (this.finished) {
       // This is a queue to the server or client to bring in the next this.
-      this._finish();
+      this.prefinish();
+      if (this.explicitfinish) {
+	    //finish MUST NOT be called when connection is not assigned
+	    //message was already finished and finish callback was not in the queue
+	    assert(this.connection);
+	    this.emit('finish');
+      }
+
     } else if (ret) {
       // This is necessary to prevent https from breaking
       this.emit('drain');