Added tests for LRUCache.

Moved core test code to reflect changes in core code.

Removed unused using directives.

src/GameServiceWarden.Core/Collection/LRUCache.cs

@@ -1,9 +1,10 @@
 using System;
+using System.Collections;
 using System.Collections.Generic;
 
-namespace GameServiceWarden.Core.Module
+namespace GameServiceWarden.Core.Collection
 {
-    public class LRUCache<K, V>
+    public class LRUCache<K, V> : IEnumerable<V>
     {
         private class Node
         {
@@ -14,7 +15,7 @@ namespace GameServiceWarden.Core.Module
         }
 
         public int Size {get { return size; } }
-        public int Length {get { return valueDictionary.Count; } }
+        public int Count {get { return valueDictionary.Count; } }
         private readonly int size;
         private Node top;
         private Node bottom;
@@ -49,7 +50,7 @@ namespace GameServiceWarden.Core.Module
                 bottom = node;
             } else if (valueDictionary.Count == Size) {
                 valueDictionary.Remove(bottom.key);
-                cleanupAction(bottom.value);
+                cleanupAction?.Invoke(bottom.value);
                 bottom = bottom.front;
             }
             valueDictionary[key] = node;
@@ -68,10 +69,27 @@ namespace GameServiceWarden.Core.Module
             return value.value;
         }
 
+        public bool IsCached(K key) {
+            return valueDictionary.ContainsKey(key);
+        }
+
         public void Clear() {
             top = null;
             bottom = null;
             valueDictionary.Clear();
         }
+
+        public IEnumerator<V> GetEnumerator()
+        {
+            foreach (Node node in valueDictionary.Values)
+            {
+                yield return node.value;
+            }
+        }
+
+        IEnumerator IEnumerable.GetEnumerator()
+        {
+            throw new NotImplementedException();
+        }
     }
 }

src/GameServiceWarden.Core/Module/ServiceManager.cs

@@ -2,14 +2,10 @@ using System;
 using System.Collections.Concurrent;
 using System.Collections.Generic;
 using System.Collections.Immutable;
-using System.Collections.ObjectModel;
-using System.IO;
-using System.IO.Pipes;
-using System.Linq;
 using GameServiceWarden.API.Games;
 using GameServiceWarden.Core.Persistence;
 using GameServiceWarden.API.Module;
-using System.Text;
+using GameServiceWarden.Core.Collection;
 
 namespace GameServiceWarden.Core.Module
 {

tests/GameServiceWarden.Core.Tests/Collection/FakeDisposable.cs

@@ -0,0 +1,36 @@
+using System;
+
+namespace GameServiceWarden.Core.Tests.Collection
+{
+    public class FakeDisposable : IDisposable
+    {
+        private string value;
+        private bool disposedValue;
+
+        public FakeDisposable(string value)
+        {
+            this.value = value;
+        }
+        
+        public bool IsDisposed() {
+            return disposedValue;
+        }
+
+        protected virtual void Dispose(bool disposing)
+        {
+            if (!disposedValue)
+            {
+                if (disposing)
+                {
+                }
+                disposedValue = true;
+            }
+        }
+
+        public void Dispose()
+        {
+            Dispose(disposing: true);
+            GC.SuppressFinalize(this);
+        }
+    }
+}

tests/GameServiceWarden.Core.Tests/Collection/LRUCacheTest.cs

@@ -0,0 +1,72 @@
+using GameServiceWarden.Core.Collection;
+using Xunit;
+
+namespace GameServiceWarden.Core.Tests.Collection
+{
+    public class LRUCacheTest
+    {
+        [Fact]
+        public void Use_SufficientSpace_StoredUsed()
+        {
+            //Given
+            string data = "data";
+            LRUCache<int, string> cache = new LRUCache<int, string>(10);
+            //When
+            cache.Use(0, () => data);
+            //Then
+            Assert.Same(data, cache.Use(0, () => "other"));
+        }
+
+        [Fact]
+        public void Use_InsufficientSpace_LastUsedRemoved()
+        {
+            //Given
+            string[] data = new string[] { "a", "b", "c" };
+            LRUCache<int, string> cache = new LRUCache<int, string>(2);
+            //When
+            for (int i = 0; i < data.Length; i++)
+            {
+                cache.Use(i, () => data[i]);
+            }
+            //Then
+            Assert.Contains("c", cache);
+            Assert.Contains("b", cache);
+            Assert.DoesNotContain("a", cache);
+        }
+
+        [Fact]
+        public void IsCached_CachedData_True()
+        {
+            //Given
+            string[] data = new string[] { "a", "b", "c" };
+            LRUCache<int, string> cache = new LRUCache<int, string>(2);
+            //When
+            for (int i = 0; i < data.Length; i++)
+            {
+                cache.Use(i, () => data[i]);
+            }
+            //Then
+            Assert.True(cache.IsCached(2));
+            Assert.True(cache.IsCached(1));
+            Assert.False(cache.IsCached(0));
+        }
+
+        [Fact]
+        public void Use_CleanupDelSet_DataChanged()
+        {
+            //Given
+            FakeDisposable[] data = new FakeDisposable[] { new FakeDisposable("a"), new FakeDisposable("b"), new FakeDisposable("c")};
+            LRUCache<int, FakeDisposable> cache = new LRUCache<int, FakeDisposable>(2, (d) => d.Dispose());
+            //When
+            for (int i = 0; i < data.Length; i++)
+            {
+                cache.Use(i, () => data[i]);
+            }
+            //Then
+            Assert.True(data[0].IsDisposed());
+            Assert.False(data[1].IsDisposed());
+            Assert.False(data[2].IsDisposed());
+        }
+
+    }
+}

tests/GameServiceWarden.Core.Tests/Modules/FakeService.cs

@@ -4,7 +4,7 @@ using System.IO;
 using System.Threading.Tasks;
 using GameServiceWarden.API.Module;
 
-namespace GameServiceWarden.Core.Tests.Modules.Games
+namespace GameServiceWarden.Core.Tests.Modules
 {
     public class FakeService : IService
     {

tests/GameServiceWarden.Core.Tests/Modules/FakeServiceConfigurable.cs

@@ -1,6 +1,6 @@
 using GameServiceWarden.API.Module;
 
-namespace GameServiceWarden.Core.Tests.Modules.Games
+namespace GameServiceWarden.Core.Tests.Modules
 {
     public class FakeServiceConfigurable : IServiceConfigurable
     {

tests/GameServiceWarden.Core.Tests/Modules/FakeServiceManagerMonitor.cs

@@ -3,7 +3,7 @@ using System.Collections.Generic;
 using GameServiceWarden.API.Games;
 using GameServiceWarden.Core.Module;
 
-namespace GameServiceWarden.Core.Tests.Modules.Games
+namespace GameServiceWarden.Core.Tests.Modules
 {
     public class FakeServiceManagerMonitor : IServiceManagerMonitor
     {

tests/GameServiceWarden.Core.Tests/Modules/FakeServiceModule.cs

@@ -1,7 +1,7 @@
 using System.Collections.Generic;
 using GameServiceWarden.API.Module;
 
-namespace GameServiceWarden.Core.Tests.Modules.Games
+namespace GameServiceWarden.Core.Tests.Modules
 {
     public class FakeServiceModule : IServiceModule
     {

tests/GameServiceWarden.Core.Tests/Modules/ServiceDescriptorTest.cs

@@ -7,7 +7,7 @@ using Xunit;
 using Xunit.Abstractions;
 using System.Text;
 
-namespace GameServiceWarden.Core.Tests.Modules.Games
+namespace GameServiceWarden.Core.Tests.Modules
 {
     // Testing convention from: https://docs.microsoft.com/en-us/dotnet/core/testing/unit-testing-best-practices
     // fakes are generic test objects, 

tests/GameServiceWarden.Core.Tests/Modules/ServiceManagerTest.cs

@@ -12,7 +12,7 @@ using Xunit.Abstractions;
 using System.Text;
 
 [assembly: CollectionBehavior(DisableTestParallelization = true)]
-namespace GameServiceWarden.Core.Tests.Modules.Games
+namespace GameServiceWarden.Core.Tests.Modules
 {
     [CollectionDefinition("Service")]
     public class ServiceManagerTest

tests/GameServiceWarden.Core.Tests/Persistence/ServiceDescriptorPersistenceTest.cs

@@ -1,10 +1,8 @@
-using System.Collections;
 using System.Collections.Generic;
 using System.IO;
 using GameServiceWarden.Core.Module;
 using GameServiceWarden.Core.Persistence;
 using GameServiceWarden.Core.Tests.Modules;
-using GameServiceWarden.Core.Tests.Modules.Games;
 using GameServiceWarden.API.Module;
 using Xunit;