I think #110 is finally fixed

Author: chester89

src/FluentNHibernate.Testing/DomainModel/Mapping/CompositeIdentityPartTester.cs

@@ -1,5 +1,8 @@
 using System;
+using System.Linq;
 using FluentNHibernate.Mapping;
+using FluentNHibernate.Mapping.Providers;
+using FluentNHibernate.MappingModel.ClassBased;
 using NUnit.Framework;
 
 namespace FluentNHibernate.Testing.DomainModel.Mapping
@@ -207,5 +210,12 @@ public class ComponentKey
             public virtual int KeyCol1 { get; set; }
             public virtual int KeyCol2 { get; set; }
         }
+
+        [Test]
+        public void Can_Have_Multiple_key_Columns()
+        {
+            var provider = (IIndeterminateSubclassMappingProvider)new MultipleKeyColumnsTester.TestMap();
+            provider.GetSubclassMapping(SubclassType.JoinedSubclass).Key.Columns.Count().ShouldEqual(2);
+        }
     }
 }

src/FluentNHibernate.Testing/DomainModel/Mapping/MultipleKeyColumnsTester.cs

@@ -0,0 +1,36 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using FluentNHibernate.Mapping;
+using FluentNHibernate.Mapping.Providers;
+using FluentNHibernate.MappingModel.ClassBased;
+using NUnit.Framework;
+
+namespace FluentNHibernate.Testing.DomainModel.Mapping
+{
+    [TestFixture]
+    public class MultipleKeyColumnsTester
+    {
+        [Test]
+        public void CanHaveMultipleKeyColumns()
+        {
+            var provider = (IIndeterminateSubclassMappingProvider)new TestMap();
+            provider.GetSubclassMapping(SubclassType.JoinedSubclass).Key.Columns.Count().ShouldEqual(2);
+        }
+
+        public class Base
+        {
+            public int Id { get; set; }
+        }
+
+        public class TestMap : SubclassMap<Base>
+        {
+            public TestMap()
+            {
+                KeyColumn("col1");
+                KeyColumn("col2");
+            }
+        }
+    }
+}

src/FluentNHibernate.Testing/FluentNHibernate.Testing.csproj

@@ -121,6 +121,7 @@
     <Compile Include="AutoMapping\Overrides\CompositeIdOverrides.cs" />
     <Compile Include="AutoMapping\Overrides\HibernateMappingOverrides.cs" />
     <Compile Include="DomainModel\Mapping\ManyToManySelfReferencedInverseIntegrationTester.cs" />
+    <Compile Include="DomainModel\Mapping\MultipleKeyColumnsTester.cs" />
     <Compile Include="DomainModel\MemberAccessResolverTests.cs" />
     <Compile Include="DomainModel\MemberBackingFieldTests.cs" />
     <Compile Include="DomainModel\NamingTests.cs" />