Revert "voice: remove passes (discord will begin dropping duplicated …

…audio packets from tomorrow, you should not set passes > 1)"

This reverts commit 8457b88.

docs/topics/voice.md

@@ -70,10 +70,13 @@ We can also pass in options when we first play the stream:
 
 ```js
 const dispatcher = connection.play('/home/discord/audio.mp3', {
-  volume: 0.5
+  volume: 0.5,
+  passes: 3
 });
 ```
 
+These are just a subset of the options available (consult documentation for a full list). Most users may be interested in the `passes` option, however. As audio is sent over UDP, there is a chance packets may not arrive. Increasing the number of passes, e.g. to `3` gives you a better chance that your packets reach your recipients, at the cost of triple the bandwidth. We recommend not going over 5 passes.
+
 ### What can I play?
 
 Discord.js allows you to play a lot of things:

src/client/voice/dispatcher/StreamDispatcher.js

@@ -33,9 +33,9 @@ const nonce = Buffer.alloc(24);
 class StreamDispatcher extends Writable {
   constructor(
     player,
-    { seek = 0, volume = 1, fec, plp, bitrate = 96, highWaterMark = 12 } = {},
+    { seek = 0, volume = 1, passes = 1, fec, plp, bitrate = 96, highWaterMark = 12 } = {},
     streams) {
-    const streamOptions = { seek, volume, fec, plp, bitrate, highWaterMark };
+    const streamOptions = { seek, volume, passes, fec, plp, bitrate, highWaterMark };
     super(streamOptions);
     /**
      * The Audio Player that controls this dispatcher
@@ -289,21 +289,24 @@ class StreamDispatcher extends Writable {
   }
 
   _sendPacket(packet) {
+    let repeats = this.streamOptions.passes;
     /**
      * Emitted whenever the dispatcher has debug information.
      * @event StreamDispatcher#debug
      * @param {string} info The debug info
      */
     this._setSpeaking(1);
-    if (!this.player.voiceConnection.sockets.udp) {
-      this.emit('debug', 'Failed to send a packet - no UDP socket');
-      return;
+    while (repeats--) {
+      if (!this.player.voiceConnection.sockets.udp) {
+        this.emit('debug', 'Failed to send a packet - no UDP socket');
+        return;
+      }
+      this.player.voiceConnection.sockets.udp.send(packet)
+        .catch(e => {
+          this._setSpeaking(0);
+          this.emit('debug', `Failed to send a packet - ${e}`);
+        });
     }
-    this.player.voiceConnection.sockets.udp.send(packet)
-      .catch(e => {
-        this._setSpeaking(0);
-        this.emit('debug', `Failed to send a packet - ${e}`);
-      });
   }
 
   _setSpeaking(value) {

src/client/voice/util/PlayInterface.js

@@ -11,6 +11,7 @@ const { Error } = require('../../../errors');
  * @property {number} [seek=0] The time to seek to, will be ignored when playing `ogg/opus` or `webm/opus` streams
  * @property {number|boolean} [volume=1] The volume to play at. Set this to false to disable volume transforms for
  * this stream to improve performance.
+ * @property {number} [passes=1] How many times to send the voice packet to reduce packet loss
  * @property {number} [plp] Expected packet loss percentage
  * @property {boolean} [fec] Enabled forward error correction
  * @property {number|string} [bitrate=96] The bitrate (quality) of the audio in kbps.

typings/index.d.ts

@@ -2514,6 +2514,7 @@ declare module 'discord.js' {
 		type?: StreamType;
 		seek?: number;
 		volume?: number | boolean;
+		passes?: number;
 		plp?: number;
 		fec?: boolean;
 		bitrate?: number | 'auto';