From 5ebba786d50077365b55c193df2d570bf5498b6e Mon Sep 17 00:00:00 2001
From: Feross Aboukhadijeh <feross@feross.org>
Date: Wed, 11 May 2016 18:30:39 +0200
Subject: [PATCH] On duplicate torrent add, don't emit 'infoHash'

Private 'infoHash' event allows client.add to check for duplicate
torrents and destroy them before the normal 'infoHash' event is
emitted. Prevents user applications from needing to deal with duplicate
'infoHash' events.
---
 CHANGELOG.md   | 4 ++++
 index.js       | 4 ++--
 lib/torrent.js | 8 +++++++-
 3 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8b85b504..5d09b84a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 # WebTorrent Version History
 
+## UNRELEASED
+
+- When a duplicate torrent is added, don't emit the 'infoHash' event after 'error'. The 'error' event should be the last event.
+
 ## v0.93.1 - 2016-05-08
 
 - Remove `path-exists` dependency.
diff --git a/index.js b/index.js
index f8194da5..3a69d3c9 100644
--- a/index.js
+++ b/index.js
@@ -240,7 +240,7 @@ WebTorrent.prototype.add = function (torrentId, opts, ontorrent) {
   var torrent = new Torrent(torrentId, self, opts)
   self.torrents.push(torrent)
 
-  torrent.once('infoHash', onInfoHash)
+  torrent.once('_infoHash', onInfoHash)
   torrent.once('ready', onReady)
   torrent.once('close', onClose)
 
@@ -262,7 +262,7 @@ WebTorrent.prototype.add = function (torrentId, opts, ontorrent) {
   }
 
   function onClose () {
-    torrent.removeListener('infoHash', onInfoHash)
+    torrent.removeListener('_infoHash', onInfoHash)
     torrent.removeListener('ready', onReady)
     torrent.removeListener('close', onClose)
   }
diff --git a/lib/torrent.js b/lib/torrent.js
index a765ef8b..2e082b90 100644
--- a/lib/torrent.js
+++ b/lib/torrent.js
@@ -253,8 +253,14 @@ Torrent.prototype._onParsedTorrent = function (parsedTorrent) {
   }, RECHOKE_INTERVAL)
   if (self._rechokeIntervalId.unref) self._rechokeIntervalId.unref()
 
+  // Private 'infoHash' event allows client.add to check for duplicate torrents and
+  // destroy them before the normal 'infoHash' event is emitted. Prevents user
+  // applications from needing to deal with duplicate 'infoHash' events.
+  self.emit('_infoHash', self.infoHash)
+  if (self.destroyed) return
+
   self.emit('infoHash', self.infoHash)
-  if (self.destroyed) return // user might destroy torrent in `infoHash` event handler
+  if (self.destroyed) return // user might destroy torrent in event handler
 
   if (self.client.listening) {
     self._onListening()