Merge pull request #30 from boraaros/fix/nullable-warnings

Fix/nullable warnings

Author: boraaros

Alligator.Demo/Program.cs

@@ -83,7 +83,7 @@ private static Placement HumanStep()
             {
                 try
                 {
-                    string[] msg = Console.ReadLine().Split(':');
+                    string[] msg = (Console.ReadLine() ?? string.Empty).Split(':');
                     return new Placement(int.Parse(msg[0]), int.Parse(msg[1]));
                 }
                 catch (Exception e)

Alligator.SixMaking/Logics/IMovingRules.cs

@@ -1,4 +1,4 @@
-using Alligator.SixMaking.Model;
+using Alligator.SixMaking.Model;
 
 namespace Alligator.SixMaking.Logics
 {

Alligator.SixMaking/Logics/Rules.cs

@@ -40,7 +40,7 @@ public IEnumerable<Step> LegalStepsAt(IPosition position)
                         {
                             var move = stepPool.GetMovement(cell, to, diskCount);
 
-                            if (movingRules.AreInverses(position.LastStep, move))
+                            if (position.LastStep is not null && movingRules.AreInverses(position.LastStep, move))
                             {
                                 continue;
                             }

Alligator.SixMaking/Model/IPosition.cs

@@ -5,7 +5,7 @@ namespace Alligator.SixMaking.Model
     public interface IPosition : IPosition<Step>
     {
         Disk Next { get; }
-        Step LastStep { get; }
+        Step? LastStep { get; }
         IList<Step> History { get; }
         int ColumnHeightAt(int cell);
         Disk DiskAt(int cell, int height);

Alligator.SixMaking/Model/Position.cs

@@ -32,7 +32,7 @@ public Position(IList<Step> history)
 
         public bool IsOver => winner != Disk.None;
 
-        public Step LastStep => History.LastOrDefault();
+        public Step? LastStep => History.LastOrDefault();
 
         public sbyte Value => StaticEvaluate();
 

Alligator.SixMaking/Model/Step.cs

@@ -31,7 +31,7 @@ public int Count
             get { return count; }
         }
 
-        public override bool Equals(object obj)
+        public override bool Equals(object? obj)
         {
             if (obj is not Step other)
             {

Alligator.SixMaking/Program.cs

@@ -84,7 +84,7 @@ private static Step HumanStep()
             {
                 try
                 {
-                    string[] msg = Console.ReadLine().Split(':');
+                    string[] msg = (Console.ReadLine() ?? string.Empty).Split(':');
                     int from = int.Parse(msg[0]);
                     int to = int.Parse(msg[1]);
                     int count = int.Parse(msg[2]);

Alligator.SixMaking/Singleton.cs

@@ -2,7 +2,7 @@
 {
     public class ZobristHashing : IHashing
     {
-        private static ulong[] randomULongs;
+        private static ulong[] randomULongs = null!;
         private ulong hashValue;
 
         private static readonly Random random =

Alligator.SixMaking/ZobristHashing.cs

@@ -77,7 +77,7 @@ private int SearchRecursively(TPosition position, int depth, int alpha, int beta
             }
 
             var bestValue = -int.MaxValue;
-            TStep bestStep = default;
+            TStep bestStep = orderedSteps[0];
 
             for (int i = 0; i < orderedSteps.Count; i++)
             {
@@ -117,7 +117,7 @@ private List<TStep> GetOrderedLegalSteps(TPosition position, int depth, bool has
 
             foreach (var move in rules.LegalStepsAt(position))
             {
-                if (hasTransposition && move.Equals(transpositionStep))
+                if (hasTransposition && move!.Equals(transpositionStep))
                 {
                     transpositionStepIsLegal = true;
                     continue;