[ServiceEntry] Add hashable class that contains a service type and se…

…rvice key, to store in a dictionary and access by both type and key.

Wingman.Tests/Container/ServiceEntryTests.cs

@@ -0,0 +1,61 @@
+namespace Wingman.Tests.Container
+{
+    using Wingman.Container;
+
+    using Xunit;
+
+    public class ServiceEntryTests
+    {
+        [Fact]
+        public void TestIdenticalEntriesIdenticalHashCode()
+        {
+            ServiceEntry serviceEntry0 = new ServiceEntry(typeof(IService), "SomeKey");
+            ServiceEntry serviceEntry1 = new ServiceEntry(typeof(IService), "SomeKey");
+
+            int hashCode0 = serviceEntry0.GetHashCode();
+            int hashCode1 = serviceEntry1.GetHashCode();
+
+            Assert.Equal(hashCode0, hashCode1);
+        }
+
+        [Fact]
+        public void TestNullServiceMatches()
+        {
+            ServiceEntry serviceEntry0 = new ServiceEntry(typeof(IService), null);
+            ServiceEntry serviceEntry1 = new ServiceEntry(typeof(IService), null);
+
+            int hashCode0 = serviceEntry0.GetHashCode();
+            int hashCode1 = serviceEntry1.GetHashCode();
+
+            Assert.Equal(hashCode0, hashCode1);
+        }
+
+        [Fact]
+        public void TestNullKeyMatches()
+        {
+            ServiceEntry serviceEntry0 = new ServiceEntry(null, "SomeKey");
+            ServiceEntry serviceEntry1 = new ServiceEntry(null, "SomeKey");
+
+            int hashCode0 = serviceEntry0.GetHashCode();
+            int hashCode1 = serviceEntry1.GetHashCode();
+
+            Assert.Equal(hashCode0, hashCode1);
+        }
+
+        [Fact]
+        public void TestDifferentEntriesDifferentHashCode()
+        {
+            ServiceEntry serviceEntry0 = new ServiceEntry(typeof(IService), "SomeKey");
+            ServiceEntry serviceEntry1 = new ServiceEntry(typeof(IService1), "SomeKey");
+
+            int hashCode0 = serviceEntry0.GetHashCode();
+            int hashCode1 = serviceEntry1.GetHashCode();
+
+            Assert.NotEqual(hashCode0, hashCode1);
+        }
+
+        private interface IService { }
+
+        private interface IService1 { }
+    }
+}

Wingman/Container/ServiceEntry.cs

@@ -0,0 +1,33 @@
+namespace Wingman.Container
+{
+    using System;
+
+    internal class ServiceEntry
+    {
+        private readonly Type _serviceType;
+
+        private readonly string _key;
+
+        internal ServiceEntry(Type serviceType, string key)
+        {
+            _serviceType = serviceType;
+            _key = key;
+        }
+
+        public override int GetHashCode()
+        {
+            unchecked
+            {
+                const int prime1 = 17;
+                const int prime2 = 23;
+
+                int hash = prime1;
+
+                hash = (hash * prime2) + (_serviceType?.GetHashCode() ?? 0);
+                hash = (hash * prime2) + (_key?.GetHashCode() ?? 0);
+
+                return hash;
+            }
+        }
+    }
+}