Add SocketUser.MutualGuilds + various ext. methods.

src/Discord.Net.Commands/Extensions/CommandServiceExtensions.cs

@@ -0,0 +1,27 @@
+using System;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+
+namespace Discord.Commands
+{
+    public static class CommandServiceExtensions
+    {
+        public static async Task<IReadOnlyCollection<CommandInfo>> GetExecutableCommandsAsync(this IEnumerable<CommandInfo> commands, ICommandContext context, IServiceProvider provider)
+        {
+            var executableCommands = new List<CommandInfo>();
+
+            foreach (var command in commands)
+            {
+                var result = await command.CheckPreconditionsAsync(context, provider).ConfigureAwait(false);
+                if (result.IsSuccess)
+                    executableCommands.Add(command);
+            }
+
+            return executableCommands;
+        }
+        public static Task<IReadOnlyCollection<CommandInfo>> GetExecutableCommandsAsync(this CommandService commandService, ICommandContext context, IServiceProvider provider)
+            => GetExecutableCommandsAsync(commandService.Commands, context, provider);
+        public static Task<IReadOnlyCollection<CommandInfo>> GetExecutableCommandAsync(this ModuleInfo module, ICommandContext context, IServiceProvider provider)
+            => GetExecutableCommandsAsync(module.Commands, context, provider);
+    }
+}

src/Discord.Net.Core/Extensions/EmbedBuilderExtensions.cs

@@ -1,4 +1,6 @@
 using System;
+using System.Collections.Generic;
+using System.Linq;
 
 namespace Discord
 {
@@ -54,5 +56,15 @@ namespace Discord
 
             return builder;
         }
+
+        public static EmbedBuilder WithFields(this EmbedBuilder builder, IEnumerable<EmbedFieldBuilder> fields)
+        {
+            foreach (var field in fields)
+                builder.AddField(field);
+
+            return builder;
+        }
+        public static EmbedBuilder WithFields(this EmbedBuilder builder, params EmbedFieldBuilder[] fields)
+            => WithFields(builder, fields.AsEnumerable());
     }
 }

src/Discord.Net.WebSocket/Entities/Users/SocketUser.cs

@@ -1,5 +1,7 @@
-using Discord.Rest;
+using Discord.Rest;
 using System;
+using System.Collections.Generic;
+using System.Linq;
 using System.Threading.Tasks;
 using Model = Discord.API.User;
 
@@ -20,6 +22,8 @@ namespace Discord.WebSocket
         public string Mention => MentionUtils.MentionUser(Id);
         public IActivity Activity => Presence.Activity;
         public UserStatus Status => Presence.Status;
+        public IEnumerable<SocketGuild> MutualGuilds
+            => Discord.Guilds.Where(g => g.Users.Any(u => u.Id == Id));
 
         internal SocketUser(DiscordSocketClient discord, ulong id)
             : base(discord, id)