Implement 'Modify Guild Channel Positions' (#1198)

* Adding shuffleArray method to utils

* Shuffle channels functionality on guild.

* Comment fix

* Removing shuffle functionality and replacing with a simple update

* Code review changes to method/variable names

* Update comment reference to channelId as well

* Updating jsdoc with typedef of ChannelPosition

src/client/actions/ActionsManager.js

@@ -28,6 +28,7 @@ class ActionsManager {
     this.register(require('./GuildEmojiDelete'));
     this.register(require('./GuildEmojiUpdate'));
     this.register(require('./GuildRolesPositionUpdate'));
+    this.register(require('./GuildChannelsPositionUpdate'));
   }
 
   register(Action) {

src/client/actions/GuildChannelsPositionUpdate.js

@@ -0,0 +1,23 @@
+const Action = require('./Action');
+
+class GuildChannelsPositionUpdate extends Action {
+  handle(data) {
+    const client = this.client;
+
+    const guild = client.guilds.get(data.guild_id);
+    if (guild) {
+      for (const partialChannel of data.channels) {
+        const channel = guild.roles.get(partialChannel.id);
+        if (channel) {
+          channel.position = partialChannel.position;
+        }
+      }
+    }
+
+    return {
+      guild,
+    };
+  }
+}
+
+module.exports = GuildChannelsPositionUpdate;

src/client/rest/RESTMethods.js

@@ -751,6 +751,15 @@ class RESTMethods {
       .then(() => user);
   }
 
+  updateChannelPositions(guildID, channels) {
+    return this.rest.makeRequest('patch', Constants.Endpoints.guildChannels(guildID), true, channels).then(() =>
+      this.client.actions.GuildChannelsPositionUpdate.handle({
+        guild_id: guildID,
+        channels,
+      }).guild
+    );
+  }
+
   setRolePositions(guildID, roles) {
     return this.rest.makeRequest('patch', Constants.Endpoints.guildRoles(guildID), true, roles).then(() =>
       this.client.actions.GuildRolesPositionUpdate.handle({

src/structures/Guild.js

@@ -633,7 +633,27 @@ class Guild {
    *  .catch(console.error);
    */
   createChannel(name, type, overwrites) {
-    return this.client.rest.methods.createChannel(this, name, type, overwrites);
+    return this.client.rest.methods.updateChannel(this, name, type, overwrites);
+  }
+
+  /**
+   * The data needed for updating a channel's position.
+   * @typedef {Object} ChannelPosition
+   * @property {string} id The channel being updated's unique id.
+   * @property {number} position The new position of the channel.
+   */
+
+  /**
+   * Updates this guild's channel positions as a batch.
+   * @param {Array<ChannelPosition>} channelPositions Array of objects that defines which channel is going where.
+   * @returns {Promise<Guild>}
+   * @example
+   * guild.updateChannels([{ id: channelID, position: newChannelIndex }])
+   *  .then(guild => console.log(`Updated channels for ${guild.id}`))
+   *  .catch(console.error);
+   */
+  updateChannelPositions(channelPositions) {
+    return this.client.rest.methods.updateChannelPositions(this.id, channelPositions);
   }
 
   /**