CSHARP-708: fixed bug where interface maps were too strict with regards to mapping a member back to it's interface declaration.

Author: craiggwilson

MongoDB.Bson/Serialization/BsonClassMap.cs

@@ -1566,7 +1566,7 @@ private static MemberInfo GetMemberInfoFromLambda<TMember>(Expression<Func<TClas
                 case MemberTypes.Property:
                     if (memberInfo.DeclaringType.IsInterface)
                     {
-                        memberInfo = ResolveExplicitProperty(memberInfo, typeof(TClass));
+                        memberInfo = FindPropertyImplementation((PropertyInfo)memberInfo, typeof(TClass));
                     }
                     break;
                 default:
@@ -1585,45 +1585,32 @@ private static string GetMemberNameFromLambda<TMember>(Expression<Func<TClass, T
             return GetMemberInfoFromLambda(memberLambda).Name;
         }
 
-        private static PropertyInfo ResolveExplicitProperty(MemberInfo interfaceMemberInfo, Type targetType)
+        private static PropertyInfo FindPropertyImplementation(PropertyInfo interfacePropertyInfo, Type actualType)
         {
-            var interfaceType = interfaceMemberInfo.DeclaringType;
+            var interfaceType = interfacePropertyInfo.DeclaringType;
 
             // An interface map must be used because because there is no
             // other officially documented way to derive the explicitly
             // implemented property name.
-            var interfaceMap = targetType.GetInterfaceMap(interfaceType);
+            var interfaceMap = actualType.GetInterfaceMap(interfaceType);
 
-            var interfacePropertyAccessors = ((PropertyInfo)interfaceMemberInfo).GetAccessors(true);
+            var interfacePropertyAccessors = interfacePropertyInfo.GetAccessors(true);
 
-            var targetPropertyAccessors = interfacePropertyAccessors.Select(accessor =>
+            var actualPropertyAccessors = interfacePropertyAccessors.Select(interfacePropertyAccessor =>
             {
-                var index = Array.IndexOf<MethodInfo>(interfaceMap.InterfaceMethods, accessor);
+                var index = Array.IndexOf<MethodInfo>(interfaceMap.InterfaceMethods, interfacePropertyAccessor);
 
                 return interfaceMap.TargetMethods[index];
-            }).ToArray();
+            });
 
             // Binding must be done by accessor methods because interface
             // maps only map accessor methods and do not map properties.
-            return targetType.GetProperties(BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic)
+            return actualType.GetProperties(BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic)
                 .Single(propertyInfo =>
                 {
-                    var accessors = propertyInfo.GetAccessors(true);
-
-                    if (accessors.Length != targetPropertyAccessors.Length)
-                    {
-                        return false;
-                    }
-
-                    for (var i = 0; i < accessors.Length; ++i)
-                    {
-                        if(!targetPropertyAccessors.Contains(accessors[i]))
-                        {
-                            return false;
-                        }
-                    }
-
-                    return true;
+                    // we are looking for a property that implements all the required accessors
+                    var propertyAccessors = propertyInfo.GetAccessors(true);
+                    return actualPropertyAccessors.All(x => propertyAccessors.Contains(x));
                 });
         }
     }

MongoDB.BsonUnitTests/Jira/CSharp708Tests.cs

@@ -1,4 +1,4 @@
-/* Copyright 2010-2012 10gen Inc.
+/* Copyright 2010-2013 10gen Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
@@ -13,11 +13,8 @@
 * limitations under the License.
 */
 
-using MongoDB.Bson;
-using MongoDB.Bson.Serialization.Attributes;
-using NUnit.Framework;
 using MongoDB.Bson.Serialization;
-using MongoDB.Bson.Serialization.Conventions;
+using NUnit.Framework;
 
 namespace MongoDB.BsonUnitTests.Jira.CSharp708
 {
@@ -34,19 +31,22 @@ class Entity : IIdentity
             public string Id { get; set; }
         }
 
-        void ConfigureClassMap<T>(BsonClassMap<T> cm)
+        BsonMemberMap GetIdMemberMap<T>(BsonClassMap<T> cm)
             where T : class, IIdentity, new()
         {
-            cm.SetIdMember(cm.GetMemberMap(c => c.Id).SetRepresentation(BsonType.ObjectId));
+            return cm.GetMemberMap(x => x.Id);
         }
 
         [Test]
-        public void Test()
+        public void TestGetMemberFindsCorrectMember()
         {
             var classMap = new BsonClassMap<Entity>();
             classMap.AutoMap();
 
-            ConfigureClassMap<Entity>(classMap);
+            var memberMap = GetIdMemberMap<Entity>(classMap);
+
+            Assert.IsNotNull(memberMap);
+            Assert.AreEqual("Id", memberMap.MemberName);
         }
     }
 }