Safeguards and GetHashCode implementation

Author: asbjornu

src/FluentNHibernate/AssemblyTypeSource.cs

@@ -1,36 +1,49 @@
 using System;
 using System.Collections.Generic;
-using System.Reflection;
 using System.Linq;
+using System.Reflection;
 using FluentNHibernate.Diagnostics;
 
 namespace FluentNHibernate
 {
-    /// <summary>
-    /// Facade over an assembly for retrieving type instances.
-    /// </summary>
-    public class AssemblyTypeSource : ITypeSource
-    {
-        private readonly Assembly source;
-
-        public AssemblyTypeSource(Assembly source)
-        {
-            this.source = source;
-        }
-
-        public IEnumerable<Type> GetTypes()
-        {
-            return source.GetTypes().OrderBy(x => x.FullName);
-        }
-
-        public void LogSource(IDiagnosticLogger logger)
-        {
-            logger.LoadedFluentMappingsFromSource(this);
-        }
-
-        public string GetIdentifier()
-        {
-            return source.GetName().FullName;
-        }
-    }
+	/// <summary>
+	/// Facade over an assembly for retrieving type instances.
+	/// </summary>
+	public class AssemblyTypeSource : ITypeSource
+	{
+		readonly Assembly source;
+
+		public AssemblyTypeSource(Assembly source)
+		{
+			if (source == null) throw new ArgumentNullException("source");
+
+			this.source = source;
+		}
+
+		#region ITypeSource Members
+
+		public IEnumerable<Type> GetTypes()
+		{
+			return source.GetTypes().OrderBy(x => x.FullName);
+		}
+
+		public void LogSource(IDiagnosticLogger logger)
+		{
+			if (logger == null) throw new ArgumentNullException("logger");
+
+			logger.LoadedFluentMappingsFromSource(this);
+		}
+
+		public string GetIdentifier()
+		{
+			return source.GetName().FullName;
+		}
+
+		#endregion
+
+		public override int GetHashCode()
+		{
+			return source.GetHashCode();
+		}
+	}
 }