Fixed CSHARP-81. The IdPropertyMap for a class map should come from the highest class possible in the inheritance hierarchy.

Bson/DefaultSerializer/BsonClassMap.cs

@@ -40,6 +40,7 @@ namespace MongoDB.Bson.DefaultSerializer {
         protected string discriminator;
         protected bool discriminatorIsRequired;
         protected bool isAnonymous;
+        protected bool idPropertyMapLoaded; // lazy load idPropertyMap
         protected BsonPropertyMap idPropertyMap;
         protected List<BsonPropertyMap> propertyMaps = new List<BsonPropertyMap>();
         protected bool ignoreExtraElements = true;
@@ -82,16 +83,8 @@ namespace MongoDB.Bson.DefaultSerializer {
 
         public BsonPropertyMap IdPropertyMap {
             get {
-                if (idPropertyMap != null) {
-                    return idPropertyMap;
-                } else {
-                    var baseClassMap = BaseClassMap; // call property for lazy loading
-                    if (baseClassMap != null) {
-                        return baseClassMap.IdPropertyMap;
-                    } else {
-                        return null;
-                    }
-                }
+                if (!idPropertyMapLoaded) { LoadIdPropertyMap(); }
+                return idPropertyMap;
             }
         }
 
@@ -377,19 +370,6 @@ namespace MongoDB.Bson.DefaultSerializer {
                 propertyMaps = new List<BsonPropertyMap>(ordered.Concat(propertyMaps.Where(pm => pm.Order == int.MaxValue)));
             }
 
-            // TODO: improve Id detection algorithm (doesn't have to be perfect since BsonIdAttribute can always pinpoint the Id property)
-            // simple algorithm: first property found that ends in either "Id" or "id" or is of type ObjectId or Guid
-            if (idPropertyMap == null) {
-                idPropertyMap = propertyMaps
-                    .Where(pm =>
-                        pm.PropertyName.EndsWith("Id") ||
-                        pm.PropertyName.EndsWith("id") ||
-                        pm.PropertyType == typeof(ObjectId) ||
-                        pm.PropertyType == typeof(Guid)
-                    )
-                    .FirstOrDefault();
-            }
-
             RegisterDiscriminator(classType, discriminator);
         }
 
@@ -452,6 +432,32 @@ namespace MongoDB.Bson.DefaultSerializer {
             }
             baseClassMapLoaded = true;
         }
+
+        private void LoadIdPropertyMap() {
+            if (idPropertyMap == null) {
+                // the IdPropertyMap should be provided by the highest class possible in the inheritance hierarchy
+                var baseClassMap = BaseClassMap; // call BaseClassMap property for lazy loading
+                if (baseClassMap != null) {
+                    idPropertyMap = baseClassMap.IdPropertyMap;
+                }
+
+                // if no base class provided an idPropertyMap maybe we have one?
+                if (idPropertyMap == null) {
+                    // TODO: improve Id detection algorithm (doesn't have to be perfect since BsonIdAttribute can always pinpoint the Id property)
+                    // simple algorithm: first property found that ends in either "Id" or "id" or is of type ObjectId or Guid
+                    idPropertyMap = propertyMaps
+                        .Where(pm =>
+                            pm.PropertyName.EndsWith("Id") ||
+                            pm.PropertyName.EndsWith("id") ||
+                            pm.PropertyType == typeof(ObjectId) ||
+                            pm.PropertyType == typeof(Guid)
+                        )
+                        .FirstOrDefault();
+                }
+            }
+
+            idPropertyMapLoaded = true;
+        }
         #endregion
     }
 

BsonUnitTests/BsonUnitTests.csproj

@@ -80,6 +80,7 @@
     <Compile Include="Jira\CSharp74Tests.cs" />
     <Compile Include="DefaultSerializer\Attributes\BsonAttributeTests.cs" />
     <Compile Include="Jira\CSharp78Tests.cs" />
+    <Compile Include="Jira\CSharp81Tests.cs" />
     <Compile Include="ObjectModel\BsonDocumentTests.cs" />
     <Compile Include="ObjectModel\BsonElementTests.cs" />
     <Compile Include="ObjectModel\BsonEqualsTests.cs" />

BsonUnitTests/Jira/CSharp81Tests.cs

@@ -0,0 +1,59 @@
+/* Copyright 2010 10gen Inc.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+* http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Runtime.Serialization;
+using System.Text;
+using System.Xml;
+using NUnit.Framework;
+
+using MongoDB.Bson;
+using MongoDB.Bson.IO;
+using MongoDB.Bson.DefaultSerializer;
+using MongoDB.Bson.Serialization;
+
+namespace MongoDB.BsonUnitTests.Jira {
+    [TestFixture]
+    public class CSharp81Tests {
+        private class BaseModel {
+            [BsonId]
+            public ObjectId Id { get; set; }
+        }
+
+        private class User : BaseModel {
+            public ObjectId FriendId { get; set; }
+        }
+
+        [Test]
+        public void TestIdProperty() {
+            var u = new User { Id = ObjectId.Empty, FriendId = ObjectId.Empty };
+
+            var classMap = BsonClassMap.LookupClassMap(typeof(User));
+            var idPropertyMap = classMap.IdPropertyMap;
+            Assert.AreEqual("Id", idPropertyMap.PropertyName);
+
+            var serializer = BsonSerializer.LookupSerializer(typeof(User));
+            var idGenerator = BsonSerializer.LookupIdGenerator(typeof(ObjectId));
+            serializer.GenerateDocumentId(u);
+            Assert.IsFalse(idGenerator.IsEmpty(u.Id));
+            Assert.IsTrue(idGenerator.IsEmpty(u.FriendId));
+
+            var json = u.ToJson();
+        }
+    }
+}