Sweet C#8 Part 2 NRT

Author: Splamy

Directory.Build.targets

@@ -48,7 +48,7 @@ Download either one of the latest builds from our [nightly server](https://splam
   Will always have the latest and greatest but might not be fully stable or have broken features.
 
 #### Linux
-1. dotnet core: Get the latest `dotnet core 2.2` version by following [this tutorial](https://dotnet.microsoft.com/download/linux-package-manager/ubuntu16-04/sdk-current) and follow the steps after choosing your platform
+1. dotnet core: Get the latest `dotnet core` version by following [this tutorial](https://dotnet.microsoft.com/download/linux-package-manager/ubuntu16-04/sdk-current) and follow the steps after choosing your platform
 1. Other dependencies:
 * on **Ubuntu**:  
 Run `sudo apt-get install libopus-dev ffmpeg`
@@ -98,13 +98,13 @@ For further reading check out the [CommandSystem](https://github.com/Splamy/TS3A
 Download the git repository with `git clone --recurse-submodules https://github.com/Splamy/TS3AudioBot.git`.
 
 #### Linux
-1. Get the latest `dotnet core 2.2` version by following [this tutorial](https://dotnet.microsoft.com/download/linux-package-manager/ubuntu16-04/sdk-current) and choose your platform
+1. Get the latest `dotnet core 3.0` version by following [this tutorial](https://docs.microsoft.com/dotnet/core/install/linux-package-managers) and choose your platform
 1. Go into the directory of the repository with `cd TS3AudioBot`
-1. Execute `dotnet build --framework netcoreapp2.2 --configuration Release TS3AudioBot` to build the AudioBot
-1. The binary will be in `./TS3AudioBot/bin/Release/netcoreapp2.2` and can be run with `dotnet TS3AudioBot.dll`
+1. Execute `dotnet build --framework netcoreapp3.0 --configuration Release TS3AudioBot` to build the AudioBot
+1. The binary will be in `./TS3AudioBot/bin/Release/netcoreapp3.0` and can be run with `dotnet TS3AudioBot.dll`
 
 #### Windows
-1. Make sure you have installed `Visual Studio` with `.NET Framework 4.7.2` and the latest `dotnet core 2.2` or higher
+1. Make sure you have `Visual Studio` with the `dotnet core 3.0` development toolchain installed
 1. Build the AudioBot with Visual Studio.
 
 ## Community

README.md

@@ -1,8 +1,8 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
     <OutputType>Library</OutputType>
-    <TargetFrameworks>netcoreapp2.2;netcoreapp3.0</TargetFrameworks>
+    <TargetFrameworks>netcoreapp3.0</TargetFrameworks>
 
     <LangVersion>8.0</LangVersion>
     <PlatformTarget>AnyCPU</PlatformTarget>
@@ -12,7 +12,7 @@
   <ItemGroup>
     <PackageReference Include="NUnit" Version="3.12.0" />
     <PackageReference Include="NUnit3TestAdapter" Version="3.15.1" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.3.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.4.0" />
   </ItemGroup>
 
   <ItemGroup>

TS3ABotUnitTests/TS3ABotUnitTests.csproj

@@ -31,8 +31,8 @@ public void HistoryFileIntergrityTest()
 			string testFile = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "history.test");
 			if (File.Exists(testFile)) File.Delete(testFile);
 
-			var inv1 = new ClientList { ClientId = (ClientId)10, Uid = (Uid)"Uid1", Name = "Invoker1" };
-			var inv2 = new ClientList { ClientId = (ClientId)20, Uid = (Uid)"Uid2", Name = "Invoker2" };
+			var inv1 = new { ClientId = (ClientId)10, Uid = (Uid)"Uid1", Name = "Invoker1" };
+			var inv2 = new { ClientId = (ClientId)20, Uid = (Uid)"Uid2", Name = "Invoker2" };
 
 			var ar1 = new AudioResource("asdf", "sc_ar1", "soundcloud");
 			var ar2 = new AudioResource("./File.mp3", "me_ar2", "media");

TS3ABotUnitTests/TS3MessageParserTests.cs

@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <RuleSet Name="Rules for TSAB Project" Description="Code analysis rules for the TSAB Project." ToolsVersion="16.0">
   <Rules AnalyzerId="Microsoft.Analyzers.ManagedCodeAnalysis" RuleNamespace="Microsoft.Rules.Managed">
     <Rule Id="CA1001" Action="Warning" />
@@ -84,6 +84,7 @@
   </Rules>
   <Rules AnalyzerId="Microsoft.CodeAnalysis.CSharp" RuleNamespace="Microsoft.CodeAnalysis.CSharp">
     <Rule Id="CS8019" Action="Info" />
+    <Rule Id="CS8020" Action="Info" />
   </Rules>
   <Rules AnalyzerId="Roslynator.CSharp.Analyzers" RuleNamespace="Roslynator.CSharp.Analyzers">
     <Rule Id="RCS1010" Action="Info" />
@@ -93,4 +94,4 @@
     <Rule Id="RCS1046" Action="Info" />
     <Rule Id="RCS1057" Action="None" />
   </Rules>
-</RuleSet>
+</RuleSet>

TS3ABotUnitTests/UnitTests.cs

@@ -11,7 +11,6 @@ EndProject
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Solution Items", "Solution Items", "{ADAA5A65-0CE1-45FA-91F4-3D8D39073AB0}"
 	ProjectSection(SolutionItems) = preProject
 		.editorconfig = .editorconfig
-		Directory.Build.targets = Directory.Build.targets
 		README.md = README.md
 		TS3AudioBot.ruleset = TS3AudioBot.ruleset
 	EndProjectSection

TS3AudioBot.ruleset

@@ -21,7 +21,7 @@ public static class Filter
 	{
 		public static IFilter DefaultFilter { get; } = Ic3Filter.Instance;
 
-		public static IFilter GetFilterByName(string filter)
+		public static IFilter? GetFilterByName(string filter)
 		{
 			return filter switch
 			{

TS3AudioBot.sln

@@ -8,10 +8,11 @@
 // program. If not, see <https://opensource.org/licenses/OSL-3.0>.
 
 using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
 
 namespace TS3AudioBot.Algorithm
 {
-	public class LruCache<TK, TV>
+	public class LruCache<TK, TV> where TK : notnull
 	{
 		private readonly int maxCapacity;
 		private readonly Dictionary<TK, LinkedListNode<(TK key, TV value)>> cacheDict = new Dictionary<TK, LinkedListNode<(TK, TV)>>();
@@ -22,15 +23,15 @@ public LruCache(int capacity)
 			maxCapacity = capacity;
 		}
 
-		public bool TryGetValue(TK key, out TV value)
+		public bool TryGetValue(TK key, [MaybeNullWhen(false)] out TV value)
 		{
 			if (cacheDict.TryGetValue(key, out var node))
 			{
 				Renew(node);
 				value = node.Value.value;
 				return true;
 			}
-			value = default;
+			value = default!;
 			return false;
 		}
 
@@ -50,7 +51,7 @@ public void Set(TK key, TV value)
 			cacheDict.Add(key, node);
 		}
 
-		public void Remove(TK key) => cacheDict.Remove(key);
+		public bool Remove(TK key) => cacheDict.Remove(key);
 
 		private void Renew(LinkedListNode<(TK, TV)> node)
 		{
@@ -61,6 +62,8 @@ private void Renew(LinkedListNode<(TK, TV)> node)
 		private void RemoveOldest()
 		{
 			var node = lruList.First;
+			if (node is null)
+				return;
 			lruList.RemoveFirst();
 			cacheDict.Remove(node.Value.key);
 		}

TS3AudioBot/Algorithm/IFilterAlgorithm.cs

@@ -9,12 +9,13 @@
 
 using System;
 using System.Collections.Concurrent;
+using System.Diagnostics.CodeAnalysis;
 using System.Linq;
 using TSLib.Helper;
 
 namespace TS3AudioBot.Algorithm
 {
-	public class TimedCache<TK, TV>
+	public class TimedCache<TK, TV> where TK : notnull
 	{
 		public TimeSpan Timeout { get; }
 		private readonly ConcurrentDictionary<TK, TimedData> cachedData;
@@ -27,13 +28,13 @@ public TimedCache(TimeSpan timeout)
 			cachedData = new ConcurrentDictionary<TK, TimedData>();
 		}
 
-		public bool TryGetValue(TK key, out TV value)
+		public bool TryGetValue(TK key, [MaybeNullWhen(false)] out TV value)
 		{
 			if (!cachedData.TryGetValue(key, out var data)
 				|| Tools.Now - Timeout > data.Timestamp)
 			{
 				CleanCache();
-				value = default;
+				value = default!;
 				return false;
 			}
 			value = data.Data;

TS3AudioBot/Algorithm/LruCache.cs

@@ -51,8 +51,8 @@ public bool Active
 
 		private readonly Dictionary<ChannelId, bool> channelSubscriptionsSetup = new Dictionary<ChannelId, bool>();
 		private readonly HashSet<ClientId> clientSubscriptionsSetup = new HashSet<ClientId>();
-		private ChannelId[] channelSubscriptionsCache;
-		private ClientId[] clientSubscriptionsCache;
+		private ChannelId[] channelSubscriptionsCache = Array.Empty<ChannelId>();
+		private ClientId[] clientSubscriptionsCache = Array.Empty<ClientId>();
 		private bool subscriptionSetupChanged;
 		private readonly object subscriptionLockObj = new object();
 
@@ -64,7 +64,7 @@ public CustomTargetPipe(TsFullClient client)
 			subscriptionSetupChanged = true;
 		}
 
-		public void Write(Span<byte> data, Meta meta)
+		public void Write(Span<byte> data, Meta? meta)
 		{
 			UpdatedSubscriptionCache();
 

TS3AudioBot/Algorithm/TimedCache.cs

@@ -35,10 +35,10 @@ public class FfmpegProducer : IPlayerSource, ISampleInfo, IDisposable
 
 		private readonly ConfToolsFfmpeg config;
 
-		public event EventHandler OnSongEnd;
-		public event EventHandler<SongInfoChanged> OnSongUpdated;
+		public event EventHandler? OnSongEnd;
+		public event EventHandler<SongInfoChanged>? OnSongUpdated;
 
-		private FfmpegInstance ffmpegInstance;
+		private FfmpegInstance? ffmpegInstance;
 
 		public int SampleRate { get; } = 48000;
 		public int Channels { get; } = 2;
@@ -68,9 +68,9 @@ public TimeSpan Position
 			set => SetPosition(value);
 		}
 
-		public int Read(byte[] buffer, int offset, int length, out Meta meta)
+		public int Read(byte[] buffer, int offset, int length, out Meta? meta)
 		{
-			meta = null;
+			meta = default;
 			bool triggerEndSafe = false;
 			int read;
 
@@ -206,8 +206,7 @@ private R<FfmpegInstance, string> StartFfmpegProcess(string url, TimeSpan? offse
 				new PreciseAudioTimer(this)
 				{
 					SongPositionOffset = offset,
-				},
-				false);
+				});
 
 			return StartFfmpegProcessInternal(newInstance, arguments);
 		}
@@ -219,7 +218,7 @@ private R<FfmpegInstance, string> StartFfmpegProcessIcy(string url)
 
 			try
 			{
-				var request = WebWrapper.CreateRequest(new Uri(url)).Unwrap();
+				var request = WebWrapper.CreateRequest(url).Unwrap();
 				request.Headers["Icy-MetaData"] = "1";
 
 				var response = request.GetResponse();
@@ -233,12 +232,9 @@ private R<FfmpegInstance, string> StartFfmpegProcessIcy(string url)
 				var newInstance = new FfmpegInstance(
 					url,
 					new PreciseAudioTimer(this),
-					true)
-				{
-					IcyStream = stream,
-					IcyMetaInt = metaint,
-				};
-				newInstance.OnMetaUpdated = e => OnSongUpdated(this, e);
+					stream,
+					metaint);
+				newInstance.OnMetaUpdated = e => OnSongUpdated?.Invoke(this, e);
 
 				new Thread(() => newInstance.ReadStreamLoop(id))
 				{
@@ -259,20 +255,17 @@ private R<FfmpegInstance, string> StartFfmpegProcessInternal(FfmpegInstance inst
 		{
 			try
 			{
-				instance.FfmpegProcess = new Process
+				instance.FfmpegProcess.StartInfo = new ProcessStartInfo
 				{
-					StartInfo = new ProcessStartInfo
-					{
-						FileName = config.Path.Value,
-						Arguments = arguments,
-						RedirectStandardOutput = true,
-						RedirectStandardInput = true,
-						RedirectStandardError = true,
-						UseShellExecute = false,
-						CreateNoWindow = true,
-					},
-					EnableRaisingEvents = true,
+					FileName = config.Path.Value,
+					Arguments = arguments,
+					RedirectStandardOutput = true,
+					RedirectStandardInput = true,
+					RedirectStandardError = true,
+					UseShellExecute = false,
+					CreateNoWindow = true,
 				};
+				instance.FfmpegProcess.EnableRaisingEvents = true;
 
 				Log.Debug("Starting ffmpeg with {0}", arguments);
 				instance.FfmpegProcess.ErrorDataReceived += instance.FfmpegProcess_ErrorDataReceived;
@@ -324,25 +317,28 @@ public void Dispose()
 
 		private class FfmpegInstance
 		{
-			public Process FfmpegProcess { get; set; }
+			public Process FfmpegProcess { get; }
 			public bool HasTriedToReconnect { get; set; }
 			public string ReconnectUrl { get; }
-			public bool IsIcyStream { get; }
+			public bool IsIcyStream => IcyStream != null;
 
 			public PreciseAudioTimer AudioTimer { get; }
 			public TimeSpan? ParsedSongLength { get; set; } = null;
 
-			public Stream IcyStream { get; set; }
-			public int IcyMetaInt { get; set; }
+			public Stream? IcyStream { get; }
+			public int IcyMetaInt { get; }
 			public bool Closed { get; set; }
 
-			public Action<SongInfoChanged> OnMetaUpdated;
+			public Action<SongInfoChanged>? OnMetaUpdated;
 
-			public FfmpegInstance(string url, PreciseAudioTimer timer, bool isIcyStream)
+			public FfmpegInstance(string url, PreciseAudioTimer timer) : this(url, timer, null!, 0) { }
+			public FfmpegInstance(string url, PreciseAudioTimer timer, Stream icyStream, int icyMetaInt)
 			{
+				FfmpegProcess = new Process();
 				ReconnectUrl = url;
 				AudioTimer = timer;
-				IsIcyStream = isIcyStream;
+				IcyStream = icyStream;
+				IcyMetaInt = icyMetaInt;
 
 				HasTriedToReconnect = false;
 			}
@@ -373,7 +369,7 @@ public void FfmpegProcess_ErrorDataReceived(object sender, DataReceivedEventArgs
 				if (sender != FfmpegProcess)
 					throw new InvalidOperationException("Wrong process associated to event");
 
-				if (!ParsedSongLength.HasValue)
+				if (ParsedSongLength is null)
 				{
 					var match = FindDurationMatch.Match(e.Data);
 					if (!match.Success)
@@ -394,6 +390,9 @@ public void FfmpegProcess_ErrorDataReceived(object sender, DataReceivedEventArgs
 
 			public void ReadStreamLoop(Id id)
 			{
+				if (IcyStream is null)
+					throw new InvalidOperationException("Instance is not an icy stream");
+
 				Tools.SetLogId(id.ToString());
 				const int IcyMaxMeta = 255 * 16;
 				const int ReadBufferSize = 4096;

TS3AudioBot/Audio/CustomTargetPipe.cs

@@ -17,10 +17,10 @@ public sealed class PlayInfoEventArgs : EventArgs
 		public InvokerData Invoker { get; }
 		public PlayResource PlayResource { get; }
 		public AudioResource ResourceData => PlayResource.BaseData;
-		public MetaData MetaData => PlayResource.Meta;
-		public string SourceLink { get; }
+		public MetaData? MetaData => PlayResource.Meta;
+		public string? SourceLink { get; }
 
-		public PlayInfoEventArgs(InvokerData invoker, PlayResource playResource, string sourceLink)
+		public PlayInfoEventArgs(InvokerData invoker, PlayResource playResource, string? sourceLink)
 		{
 			Invoker = invoker;
 			PlayResource = playResource;