support new guild member role endpoints for cleaner role updates (#901)

* support new roles endpoints

* use promise chaining

* properties man

* Update RESTMethods.js

* Update RESTMethods.js

* Update RESTMethods.js

* Update RESTMethods.js

src/client/rest/RESTMethods.js

@@ -328,6 +328,23 @@ class RESTMethods {
     );
   }
 
+  addMemberRole(member, role) {
+    return this.rest.makeRequest('put', Constants.Endpoints.guildMemberRole(member.guild.id, member.id, role.id))
+      .then(() => {
+        if (!member._roles.includes(role.id)) member._roles.push(role.id);
+        return member;
+      });
+  }
+
+  removeMemberRole(member, role) {
+    return this.rest.makeRequest('delete', Constants.Endpoints.guildMemberRole(member.guild.id, member.id, role.id))
+      .then(() => {
+        const index = member._roles.indexOf(role.id);
+        if (index >= 0) member._roles.splice(index, 1);
+        return member;
+      });
+  }
+
   sendTyping(channelID) {
     return this.rest.makeRequest('post', `${Constants.Endpoints.channel(channelID)}/typing`, true);
   }

src/structures/GuildMember.js

@@ -314,7 +314,8 @@ class GuildMember {
    * @returns {Promise<GuildMember>}
    */
   addRole(role) {
-    return this.addRoles([role]);
+    if (!(role instanceof Role)) role = this.guild.roles.get(role);
+    return this.client.rest.methods.addMemberRole(this, role);
   }
 
   /**
@@ -339,7 +340,8 @@ class GuildMember {
    * @returns {Promise<GuildMember>}
    */
   removeRole(role) {
-    return this.removeRoles([role]);
+    if (!(role instanceof Role)) role = this.guild.roles.get(role);
+    return this.client.rest.methods.removeMemberRole(this, role);
   }
 
   /**

src/util/Constants.js

@@ -106,6 +106,7 @@ const Endpoints = exports.Endpoints = {
   guildIntegrations: (guildID) => `${Endpoints.guild(guildID)}/integrations`,
   guildMembers: (guildID) => `${Endpoints.guild(guildID)}/members`,
   guildMember: (guildID, memberID) => `${Endpoints.guildMembers(guildID)}/${memberID}`,
+  guildMemberRole: (guildID, memberID, roleID) => `${Endpoints.guildMember(guildID, memberID)}/roles/${roleID}}`,
   stupidInconsistentGuildEndpoint: (guildID) => `${Endpoints.guildMember(guildID, '@me')}/nick`,
   guildChannels: (guildID) => `${Endpoints.guild(guildID)}/channels`,
   guildEmojis: (guildID) => `${Endpoints.guild(guildID)}/emojis`,