From c1a4c2834991e1226f4f215852bd50d9af76791b Mon Sep 17 00:00:00 2001
From: Joongi Kim <joongi@lablup.com>
Date: Tue, 5 Apr 2016 00:01:31 +0900
Subject: [PATCH] Added loopUntilNoMoreEvents() API to wait for aribtrary code.

 * Existing APIs rely on explicit callback argument or predicate.
   This API does not require such prior information, just like
   how the node.js main loop continues or terminates.

 * To use this API to block for a specific region of code, you should
   take care of other existing callbacks using unref() and ref() methods
   to prevent them from making loopUntilNoMoreEvents() to block "longer"
   than you want.
---
 index.js       | 36 ++++++++++++++++++++++--------------
 src/deasync.cc |  5 +++--
 test.js        | 20 +++++++++++++++++---
 3 files changed, 42 insertions(+), 19 deletions(-)

diff --git a/index.js b/index.js
index 5166550..24377df 100644
--- a/index.js
+++ b/index.js
@@ -5,17 +5,17 @@
  * Copyright 2014-2015 Abbr
  * Released under the MIT license
  */
- 
+
 (function () {
-		
+
 	var fs = require('fs'),
 		path = require('path'),
 		binding;
-	
+
 	// Seed random numbers [gh-82] if on Windows. See https://github.com/laverdet/node-fibers/issues/82
 	if(process.platform === 'win32') Math.random();
-	
-		
+
+
 	// Look for binary for this platform
 	var nodeV = 'node-' + /[0-9]+\.[0-9]+/.exec(process.versions.node)[0];
 	var nodeVM = 'node-' + /[0-9]+/.exec(process.versions.node)[0];
@@ -50,27 +50,35 @@
 			function cb(e, r) {
 				err = e;
 				res = r;
-				done = true;		
+				done = true;
 			}
 		}
 	}
-	
+
 	module.exports = deasync;
-	
+
 	module.exports.sleep = deasync(function(timeout, done) {
 		setTimeout(done, timeout);
 	});
-	
+
 	module.exports.runLoopOnce = function(){
 		process._tickDomainCallback();
 		binding.run();
 	};
-	
+
+	module.exports.loopUntilNoMoreEvents = function(){
+		var more = false;
+		do {
+			process._tickDomainCallback();
+			more = binding.run();
+		} while (more);
+	};
+
 	module.exports.loopWhile = function(pred){
-	  while(pred()){
-		process._tickDomainCallback();
-		if(pred()) binding.run();
-	  }
+		while(pred()){
+			process._tickDomainCallback();
+			if(pred()) binding.run();
+		}
 	};
 
 }());
diff --git a/src/deasync.cc b/src/deasync.cc
index ccb37c6..cc7f06b 100644
--- a/src/deasync.cc
+++ b/src/deasync.cc
@@ -6,8 +6,9 @@ using namespace v8;
 
 NAN_METHOD(Run) {
   Nan::HandleScope scope;
-  uv_run(uv_default_loop(), UV_RUN_ONCE);
-  info.GetReturnValue().Set(Nan::Undefined());
+  bool _more = uv_run(uv_default_loop(), UV_RUN_ONCE);
+  v8::Local<v8::Boolean> more = Nan::New(_more);
+  info.GetReturnValue().Set(more);
 }
 
 static NAN_MODULE_INIT(init) {
diff --git a/test.js b/test.js
index fa4ca1c..74effed 100644
--- a/test.js
+++ b/test.js
@@ -21,11 +21,25 @@ var request = deasync(function (url, done) {
   }).on('error', done);
 });
 
-
+// Expected order: "1st", "2nd", "3rd", "4th"
+var sleep_without_cb_or_pred = function (timeout) {
+  setTimeout(function() { console.log('2nd'); }, timeout);
+};
+var t = setTimeout(function () {
+  console.log('4th');
+}, 2000);
+t.unref(); // should not make loopUntilNoEvents() to block
+console.log('1st');
+sleep_without_cb_or_pred(1000);
+deasync.loopUntilNoMoreEvents();
+console.log('3rd');
+t.ref();  // should make loopUntilNoEvents() to block
+deasync.loopUntilNoMoreEvents();
+
+// Expected order: ls -la, "async2", request
 setTimeout(function () {
-  console.log('async');
+  console.log('async2');
 }, 1000);
-
 console.log(exec('ls -la'));
 sleep(2000);
 console.log(request('http://nodejs.org'));