Replace locking on 'this'.

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

@@ -7,6 +7,7 @@ namespace Discord.Commands
     internal class CommandMap
     {
         static readonly char[] _whitespaceChars = new char[] { ' ', '\r', '\n' };
+        private readonly object _lockObj = new object();
 
         private readonly ConcurrentDictionary<string, CommandMapNode> _nodes;
 
@@ -27,7 +28,7 @@ public void AddCommand(Command command)
                 else
                     name = text.Substring(0, nextSpace);
 
-                lock (this)
+                lock (_lockObj)
                 {
                     var nextNode = _nodes.GetOrAdd(name, x => new CommandMapNode(x));
                     nextNode.AddCommand(nextSpace == -1 ? "" : text, nextSpace + 1, command);
@@ -46,7 +47,7 @@ public void RemoveCommand(Command command)
                 else
                     name = text.Substring(0, nextSpace);
 
-                lock (this)
+                lock (_lockObj)
                 {
                     CommandMapNode nextNode;
                     if (_nodes.TryGetValue(name, out nextNode))
@@ -69,7 +70,7 @@ public IEnumerable<Command> GetCommands(string text)
             else
                 name = text.Substring(0, nextSpace);
 
-            lock (this)
+            lock (_lockObj)
             {
                 CommandMapNode nextNode;
                 if (_nodes.TryGetValue(name, out nextNode))

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

@@ -8,6 +8,7 @@ internal class CommandMapNode
     {
         private readonly ConcurrentDictionary<string, CommandMapNode> _nodes;
         private readonly string _name;
+        private readonly object _lockObj = new object();
         private ImmutableArray<Command> _commands;
 
         public bool IsEmpty => _commands.Length == 0 && _nodes.Count == 0;
@@ -24,7 +25,7 @@ public void AddCommand(string text, int index, Command command)
             int nextSpace = text.IndexOf(' ', index);
             string name;
 
-            lock (this)
+            lock (_lockObj)
             {
                 if (text == "")
                     _commands = _commands.Add(command);
@@ -45,7 +46,7 @@ public void RemoveCommand(string text, int index, Command command)
             int nextSpace = text.IndexOf(' ', index);
             string name;
 
-            lock (this)
+            lock (_lockObj)
             {
                 if (text == "")
                     _commands = _commands.Remove(command);

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

@@ -8,6 +8,7 @@ namespace Discord.WebSocket
     internal class SocketGlobalUser : User, ISocketUser
     {
         internal override bool IsAttached => true;
+        private readonly object _lockObj = new object();
 
         private ushort _references;
 
@@ -25,13 +26,13 @@ public void AddRef()
         {
             checked
             {
-                lock (this)
+                lock (_lockObj)
                     _references++;
             }
         }
         public void RemoveRef(DiscordSocketClient discord)
         {
-            lock (this)
+            lock (_lockObj)
             {
                 if (--_references == 0)
                     discord.RemoveUser(Id);
@@ -40,14 +41,14 @@ public void RemoveRef(DiscordSocketClient discord)
 
         public override void Update(Model model, UpdateSource source)
         {
-            lock (this)
+            lock (_lockObj)
                 base.Update(model, source);
         }
         public void Update(PresenceModel model, UpdateSource source)
         {
             //Race conditions are okay here. Multiple shards racing already cant guarantee presence in order.
 
-            //lock (this)
+            //lock (_lockObj)
             //{
                 var game = model.Game != null ? new Game(model.Game) : null;
                 Presence = new Presence(game, model.Status);