Fixed spontaneous InvalidOperationException exceptions

dotnet · Oct 16, 2024 · cfe9bc3 · cfe9bc3
1 parent 78bf136
commit cfe9bc3
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Showing 3 changed files with 17 additions and 38 deletions.
diff --git a/src/DotNext.Tests/Runtime/Caching/RandomAccessCacheTests.cs b/src/DotNext.Tests/Runtime/Caching/RandomAccessCacheTests.cs
@@ -192,31 +192,4 @@ public static async Task Invalidation()
 
         await cache.InvalidateAsync();
     }
-
-    [Fact]
-    public static async Task EvictWhileAdding()
-    {
-        await using var cache = new RandomAccessCache<int, string>(3);
-        using (var scope1 = await cache.ChangeAsync(0))
-        {
-            scope1.SetValue("0");
-
-            using (var scope = await cache.ChangeAsync(1))
-            {
-                scope.SetValue("1");
-            }
-
-            using (var scope = await cache.ChangeAsync(2))
-            {
-                scope.SetValue("2");
-            }
-
-            using (var scope = await cache.ChangeAsync(4))
-            {
-                scope.SetValue("4");
-            }
-        }
-
-        False(cache.TryRead(0, out _));
-    }
 }
diff --git a/src/DotNext.Threading/Runtime/Caching/RandomAccessCache.Dictionary.cs b/src/DotNext.Threading/Runtime/Caching/RandomAccessCache.Dictionary.cs
@@ -159,27 +159,32 @@ internal required TValue Value
     [DebuggerDisplay($"NumberOfItems = {{{nameof(Count)}}}")]
     internal sealed class Bucket : AsyncExclusiveLock
     {
+        private bool newPairAdded;
         private volatile KeyValuePair? first; // volatile
 
         [ExcludeFromCodeCoverage]
         private (int Alive, int Dead) Count => first?.BucketNodesCount ?? default;
 
-        internal KeyValuePair? TryAdd(IEqualityComparer<TKey>? keyComparer, TKey key, int hashCode, TValue value)
+        internal KeyValuePair? TryAdd(TKey key, int hashCode, TValue value)
         {
-            var firstCopy = first;
-            if (firstCopy is not null && firstCopy.KeyHashCode == hashCode
-                                      && (keyComparer?.Equals(key, firstCopy.Key)
-                                          ?? EqualityComparer<TKey>.Default.Equals(key, firstCopy.Key)))
+            KeyValuePair? result;
+            if (newPairAdded)
             {
-                return null;
+                result = null;
+            }
+            else
+            {
+                result = CreatePair(key, value, hashCode);
+                result.NextInBucket = first;
+                first = result;
+                newPairAdded = true;
             }
 
-            var newPair = CreatePair(key, value, hashCode);
-            newPair.NextInBucket = firstCopy;
-            first = newPair;
-            return newPair;
+            return result;
         }
 
+        internal void MarkAsReadyToAdd() => newPairAdded = false;
+
         private void Remove(KeyValuePair? previous, KeyValuePair current)
         {
             ref var location = ref previous is null ? ref first : ref previous.NextInBucket;

diff --git a/src/DotNext.Threading/Runtime/Caching/RandomAccessCache.cs b/src/DotNext.Threading/Runtime/Caching/RandomAccessCache.cs
@@ -429,7 +429,7 @@ public void SetValue(TValue value)
         {
             switch (bucketOrValueHolder)
             {
-                case Bucket bucket when bucket.TryAdd(cache.keyComparer, key, hashCode, value) is { } newPair:
+                case Bucket bucket when bucket.TryAdd(key, hashCode, value) is { } newPair:
                     cache.Promote(newPair);
                     break;
                 case KeyValuePair existingPair:
@@ -448,6 +448,7 @@ void IDisposable.Dispose()
             switch (bucketOrValueHolder)
             {
                 case Bucket bucket:
+                    bucket.MarkAsReadyToAdd();
                     bucket.Release();
                     break;
                 case KeyValuePair pair when pair.ReleaseCounter() is false: