add disconnect event, document warn and debug events (#702)

* add documentation for events, and add a disconnect event, because i know people use that

* generate docs, and fix a hastily copied docstring

* fix permissions freak out

src/client/ClientManager.js

@@ -25,10 +25,14 @@ class ClientManager {
    * @param {function} reject Function to run when connection fails
    */
   connectToWebSocket(token, resolve, reject) {
-    this.client.emit('debug', `Authenticated using token ${token}`);
+    /**
+     * Emitted when there is debug information
+     * @event Client#debug
+     */
+    this.client.emit(Constants.Events.DEBUG, `Authenticated using token ${token}`);
     this.client.token = token;
     this.client.rest.methods.getGateway().then(gateway => {
-      this.client.emit('debug', `Using gateway ${gateway}`);
+      this.client.emit(Constants.Events.DEBUG, `Using gateway ${gateway}`);
       this.client.ws.connect(gateway);
       this.client.once(Constants.Events.READY, () => resolve(token));
     }).catch(reject);

src/client/voice/player/BasePlayer.js

@@ -48,7 +48,7 @@ class VoiceConnectionPlayer extends EventEmitter {
   killStream(stream) {
     const streams = this.processMap.get(stream);
     this._streamingData = this.dispatcher.streamingData;
-    this.emit('debug', 'Cleaning up player after audio stream ended or encountered an error');
+    this.emit(Constants.Events.DEBUG, 'Cleaning up player after audio stream ended or encountered an error');
 
     const dummyHandler = () => null;
 
@@ -62,25 +62,25 @@ class VoiceConnectionPlayer extends EventEmitter {
           streams.pcmConverter.stdout.once('error', dummyHandler);
           if (streams.inputStream.unpipe) {
             streams.inputStream.unpipe(streams.pcmConverter.stdin);
-            this.emit('debug', '- Unpiped input stream');
+            this.emit(Constants.Events.DEBUG, '- Unpiped input stream');
           } else if (streams.inputStream.destroy) {
             streams.inputStream.destroy();
-            this.emit('debug', '- Couldn\'t unpipe input stream, so destroyed input stream');
+            this.emit(Constants.Events.DEBUG, '- Couldn\'t unpipe input stream, so destroyed input stream');
           }
           if (streams.pcmConverter.stdin) {
             streams.pcmConverter.stdin.end();
-            this.emit('debug', '- Ended input stream to PCM converter');
+            this.emit(Constants.Events.DEBUG, '- Ended input stream to PCM converter');
           }
           if (streams.pcmConverter && streams.pcmConverter.kill) {
             streams.pcmConverter.kill('SIGINT');
-            this.emit('debug', '- Killed the pcm converter');
+            this.emit(Constants.Events.DEBUG, '- Killed the pcm converter');
           }
         } catch (err) {
           // if an error happened make sure the pcm converter is killed anyway
           try {
             if (streams.pcmConverter && streams.pcmConverter.kill) {
               streams.pcmConverter.kill('SIGINT');
-              this.emit('debug', '- Killed the pcm converter after previous error (abnormal)');
+              this.emit(Constants.Events.DEBUG, '- Killed the pcm converter after previous error (abnormal)');
             }
           } catch (e) {
             return e;

src/client/websocket/WebSocketManager.js

@@ -157,6 +157,11 @@ class WebSocketManager {
    * @param {Object} event The received websocket data
    */
   eventClose(event) {
+    /**
+     * Emitted whenever the client websocket is disconnected
+     * @event Client#disconnect
+     */
+    if (!this.reconnecting) this.client.emit(Constants.Events.DISCONNECT);
     if (event.code === 4004) throw new Error(Constants.Errors.BAD_LOGIN);
     if (!this.reconnecting && event.code !== 1000) this.tryReconnect();
   }
@@ -224,7 +229,11 @@ class WebSocketManager {
         if (this.client.options.fetch_all_members) {
           const promises = this.client.guilds.array().map(g => g.fetchMembers());
           Promise.all(promises).then(() => this._emitReady()).catch(e => {
-            this.client.emit('warn', `Error on pre-ready guild member fetching - ${e}`);
+            /**
+             * Emitted when there is a warning
+             * @event Client#warn
+             */
+            this.client.emit(Constants.Event.WARN, `Error on pre-ready guild member fetching - ${e}`);
             this._emitReady();
           });
           return;

src/client/websocket/packets/handlers/TypingStart.js

@@ -11,7 +11,7 @@ class TypingStartHandler extends AbstractHandler {
 
     if (channel && user) {
       if (channel.type === 'voice') {
-        client.emit('warn', `Discord sent a typing packet to voice channel ${channel.id}`);
+        client.emit(Constants.Events.WARN, `Discord sent a typing packet to voice channel ${channel.id}`);
         return;
       }
       if (channel._typing.has(user.id)) {

src/util/Constants.js

@@ -163,10 +163,12 @@ exports.Events = {
   MESSAGE_CREATE: 'message',
   MESSAGE_DELETE: 'messageDelete',
   MESSAGE_UPDATE: 'messageUpdate',
+  DISCONNECT: 'disconnect',
   RECONNECTING: 'reconnecting',
   GUILD_MEMBER_SPEAKING: 'guildMemberSpeaking',
   MESSAGE_BULK_DELETE: 'messageDeleteBulk',
   CHANNEL_PINS_UPDATE: 'channelPinsUpdate',
+  DEBUG: 'debug',
 };
 
 exports.WSEvents = {