Task.Delay(0) => Task.CompletedTask (#3049)

src/Discord.Net.Commands/Builders/ModuleClassBuilder.cs

@@ -211,7 +211,7 @@ namespace Discord.Commands
                     await instance.BeforeExecuteAsync(cmd).ConfigureAwait(false);
                     instance.BeforeExecute(cmd);
 
-                    var task = method.Invoke(instance, args) as Task ?? Task.Delay(0);
+                    var task = method.Invoke(instance, args) as Task ?? Task.CompletedTask;
                     if (task is Task<RuntimeResult> resultTask)
                     {
                         return await resultTask.ConfigureAwait(false);

src/Discord.Net.Core/Audio/AudioStream.cs

@@ -27,7 +27,7 @@ namespace Discord.Audio
             ClearAsync(CancellationToken.None).GetAwaiter().GetResult();
         }
 
-        public virtual Task ClearAsync(CancellationToken cancellationToken) { return Task.Delay(0); }
+        public virtual Task ClearAsync(CancellationToken cancellationToken) { return Task.CompletedTask; }
 
         /// <inheritdoc />
         /// <exception cref="NotSupportedException">Reading stream length is not supported.</exception>

src/Discord.Net.Examples/Core/Entities/Channels/IMessageChannel.Examples.cs

@@ -49,7 +49,7 @@ namespace Discord.Net.Examples.Core.Entities.Channels
             // Another dummy method
             Task LongRunningAsync()
             {
-                return Task.Delay(0);
+                return Task.CompletedTask;
             }
 
             #region GetMessagesAsync.FromLimit.Standard

src/Discord.Net.Interactions/Builders/ModuleClassBuilder.cs

@@ -425,7 +425,7 @@ namespace Discord.Interactions.Builders
                 {
                     await instance.BeforeExecuteAsync(commandInfo).ConfigureAwait(false);
                     instance.BeforeExecute(commandInfo);
-                    var task = commandInvoker(instance, args) ?? Task.Delay(0);
+                    var task = commandInvoker(instance, args) ?? Task.CompletedTask;
 
                     if (task is Task<RuntimeResult> runtimeTask)
                     {

src/Discord.Net.Rest/BaseDiscordClient.cs

@@ -124,7 +124,7 @@ namespace Discord.Rest
             await _loggedInEvent.InvokeAsync().ConfigureAwait(false);
         }
         internal virtual Task OnLoginAsync(TokenType tokenType, string token)
-            => Task.Delay(0);
+            => Task.CompletedTask;
 
         public async Task LogoutAsync()
         {
@@ -150,7 +150,7 @@ namespace Discord.Rest
             await _loggedOutEvent.InvokeAsync().ConfigureAwait(false);
         }
         internal virtual Task OnLogoutAsync()
-            => Task.Delay(0);
+            => Task.CompletedTask;
 
         internal virtual void Dispose(bool disposing)
         {
@@ -266,10 +266,10 @@ namespace Discord.Rest
 
         /// <inheritdoc />
         Task IDiscordClient.StartAsync()
-            => Task.Delay(0);
+            => Task.CompletedTask;
         /// <inheritdoc />
         Task IDiscordClient.StopAsync()
-            => Task.Delay(0);
+            => Task.CompletedTask;
 
         /// <summary>
         ///     Creates a test entitlement to a given SKU for a given guild or user.

src/Discord.Net.Rest/DiscordRestApiClient.cs

@@ -195,8 +195,8 @@ namespace Discord.API
             LoginState = LoginState.LoggedOut;
         }
 
-        internal virtual Task ConnectInternalAsync() => Task.Delay(0);
-        internal virtual Task DisconnectInternalAsync(Exception ex = null) => Task.Delay(0);
+        internal virtual Task ConnectInternalAsync() => Task.CompletedTask;
+        internal virtual Task DisconnectInternalAsync(Exception ex = null) => Task.CompletedTask;
         #endregion
 
         #region Core

src/Discord.Net.Rest/DiscordRestClient.cs

@@ -85,7 +85,7 @@ namespace Discord.Rest
         internal override Task OnLogoutAsync()
         {
             _applicationInfo = null;
-            return Task.Delay(0);
+            return Task.CompletedTask;
         }
 
         #region Rest interactions

src/Discord.Net.Rest/Entities/Channels/RestChannel.cs

@@ -79,7 +79,7 @@ namespace Discord.Rest
         }
 
         /// <inheritdoc />
-        public virtual Task UpdateAsync(RequestOptions options = null) => Task.Delay(0);
+        public virtual Task UpdateAsync(RequestOptions options = null) => Task.CompletedTask;
         #endregion
 
         #region IChannel

src/Discord.Net.WebSocket/Audio/Streams/BufferedWriteStream.cs

@@ -187,7 +187,7 @@ namespace Discord.Audio.Streams
             do
                 cancelToken.ThrowIfCancellationRequested();
             while (_queuedFrames.TryDequeue(out _));
-            return Task.Delay(0);
+            return Task.CompletedTask;
         }
     }
 }

src/Discord.Net.WebSocket/Audio/Streams/InputStream.cs

@@ -76,7 +76,7 @@ namespace Discord.Audio.Streams
             if (_signal.CurrentCount >= MaxFrames) //1-2 seconds
             {
                 _hasHeader = false;
-                return Task.Delay(0); //Buffer overloaded
+                return Task.CompletedTask; //Buffer overloaded
             }
             if (!_hasHeader)
                 throw new InvalidOperationException("Received payload without an RTP header");
@@ -91,7 +91,7 @@ namespace Discord.Audio.Streams
                 payload: payload
             ));
             _signal.Release();
-            return Task.Delay(0);
+            return Task.CompletedTask;
         }
 
         protected override void Dispose(bool isDisposing)

src/Discord.Net.WebSocket/Audio/Streams/JitterBuffer.cs

@@ -240,7 +240,7 @@ namespace Discord.Audio.Streams
             do
                 cancelToken.ThrowIfCancellationRequested();
             while (_queuedFrames.TryDequeue(out Frame ignored));
-            return Task.Delay(0);
+            return Task.CompletedTask;
         }
     }
 }*/

src/Discord.Net.WebSocket/DiscordShardedClient.cs

@@ -428,7 +428,7 @@ namespace Discord.WebSocket
                     //Should only happen if token is changed
                     var _ = LogoutAsync(); //Signal the logout, fire and forget
                 }
-                return Task.Delay(0);
+                return Task.CompletedTask;
             };
 
             client.SentRequest += (method, endpoint, millis) => _sentRequest.InvokeAsync(method, endpoint, millis);

src/Discord.Net.WebSocket/DiscordSocketClient.cs

@@ -200,7 +200,7 @@ namespace Discord.WebSocket
                 {
                     var _ = g.DownloadUsersAsync();
                 }
-                return Task.Delay(0);
+                return Task.CompletedTask;
             };
 
             _largeGuilds = new ConcurrentQueue<ulong>();

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

@@ -1793,7 +1793,7 @@ namespace Discord.WebSocket
                     audioClient.Connected += () =>
                     {
                         _ = promise.TrySetResultAsync(_audioClient);
-                        return Task.Delay(0);
+                        return Task.CompletedTask;
                     };
 
                     _audioClient = audioClient;

src/Discord.Net.WebSocket/Net/DefaultUdpSocket.cs

@@ -92,7 +92,7 @@ namespace Discord.Net.Udp
             catch { }
 
             if (!isDisposing)
-                await (_task ?? Task.Delay(0)).ConfigureAwait(false);
+                await (_task ?? Task.CompletedTask).ConfigureAwait(false);
 
             if (_udp != null)
             {

src/Discord.Net.WebSocket/Net/DefaultWebSocketClient.cs

@@ -140,7 +140,7 @@ namespace Discord.Net.WebSockets
 
             try
             {
-                await (_task ?? Task.Delay(0)).ConfigureAwait(false);
+                await (_task ?? Task.CompletedTask).ConfigureAwait(false);
                 _task = null;
             }
             finally { _isDisconnecting = false; }

test/Discord.Net.Tests.Unit/TypeReaderTests.cs

@@ -137,6 +137,6 @@ namespace Discord
     public sealed class TestModule : ModuleBase
     {
         [Command("test")]
-        public Task TestCommand(ArgumentType arg) => Task.Delay(0);
+        public Task TestCommand(ArgumentType arg) => Task.CompletedTask;
     }
 }