Remove unnecessary null checks

src/Discord.Net.Commands/Map/CommandMapNode.cs

@@ -106,7 +106,7 @@ namespace Discord.Commands
                     name = text.Substring(index, nextSegment - index);
                     if (_nodes.TryGetValue(name, out nextNode))
                     {
-                        foreach (var cmd in nextNode.GetCommands(service, nextSegment == -1 ? "" : text, nextSegment + 1, false))
+                        foreach (var cmd in nextNode.GetCommands(service, text, nextSegment + 1, false))
                             yield return cmd;
                     }
                 }

src/Discord.Net.Core/Utils/MentionUtils.cs

@@ -173,12 +173,12 @@ namespace Discord
                 {
                     case TagHandling.Name:
                         if (user != null)
-                            return $"@{guildUser?.Nickname ?? user?.Username}";
+                            return $"@{guildUser?.Nickname ?? user.Username}";
                         else
                             return "";
                     case TagHandling.NameNoPrefix:
                         if (user != null)
-                            return $"{guildUser?.Nickname ?? user?.Username}";
+                            return $"{guildUser?.Nickname ?? user.Username}";
                         else
                             return "";
                     case TagHandling.FullName:

src/Discord.Net.WebSocket/Entities/Guilds/SocketGuild.cs

@@ -816,7 +816,7 @@ namespace Discord.WebSocket
             {
                 if (model.UserId == CurrentUser.Id)
                 {
-                    if (after.VoiceChannel != null && _audioClient.ChannelId != after.VoiceChannel?.Id)
+                    if (_audioClient.ChannelId != after.VoiceChannel?.Id)
                     {
                         _audioClient.ChannelId = after.VoiceChannel.Id;
                         await RepopulateAudioStreamsAsync().ConfigureAwait(false);
@@ -825,7 +825,7 @@ namespace Discord.WebSocket
                 else
                 {
                     await _audioClient.RemoveInputStreamAsync(model.UserId).ConfigureAwait(false); //User changed channels, end their stream
-                    if (CurrentUser.VoiceChannel != null && after.VoiceChannel?.Id == CurrentUser.VoiceChannel?.Id)
+                    if (after.VoiceChannel?.Id == CurrentUser.VoiceChannel?.Id)
                         await _audioClient.CreateInputStreamAsync(model.UserId).ConfigureAwait(false);
                 }
             }