Add assert that function in InputSystem.HandleInputCommand is correct.

Robust.Client/GameObjects/EntitySystems/InputSystem.cs

@@ -9,6 +9,7 @@ using Robust.Shared.Interfaces.GameObjects;
 using Robust.Shared.IoC;
 using Robust.Shared.Log;
 using Robust.Shared.Players;
+using Robust.Shared.Utility;
 
 namespace Robust.Client.GameObjects.EntitySystems
 {
@@ -43,6 +44,13 @@ namespace Robust.Client.GameObjects.EntitySystems
         /// <param name="message">Arguments for this event.</param>
         public void HandleInputCommand(ICommonSession session, BoundKeyFunction function, FullInputCmdMessage message)
         {
+            #if DEBUG
+
+            var funcId = _inputManager.NetworkBindMap.KeyFunctionID(function);
+            DebugTools.Assert(funcId == message.InputFunctionId, "Function ID in message does not match function.");
+
+            #endif
+
             // set state, state change is updated regardless if it is locally bound
             _cmdStates.SetState(function, message.State);
 

Robust.Shared/Input/BoundKeyMap.cs

@@ -10,9 +10,9 @@ namespace Robust.Shared.Input
     ///     A networked identifier for a <see cref="BoundKeyFunction"/>.
     /// </summary>
     [Serializable, NetSerializable]
-    public struct KeyFunctionId
+    public readonly struct KeyFunctionId : IEquatable<KeyFunctionId>
     {
-        private int _value;
+        private readonly int _value;
 
         public KeyFunctionId(int id)
         {
@@ -28,6 +28,31 @@ namespace Robust.Shared.Input
         {
             return _value.ToString();
         }
+
+        public bool Equals(KeyFunctionId other)
+        {
+            return _value == other._value;
+        }
+
+        public override bool Equals(object obj)
+        {
+            return obj is KeyFunctionId other && Equals(other);
+        }
+
+        public override int GetHashCode()
+        {
+            return _value;
+        }
+
+        public static bool operator ==(KeyFunctionId left, KeyFunctionId right)
+        {
+            return left.Equals(right);
+        }
+
+        public static bool operator !=(KeyFunctionId left, KeyFunctionId right)
+        {
+            return !left.Equals(right);
+        }
     }
 
     /// <summary>