CSHARP-5403: Fix queries and projection on GridFSFileInfo Id property.

Author: rstam

src/MongoDB.Driver/GridFS/GridFSFileInfoSerializerCompat.cs

@@ -43,6 +43,7 @@ public GridFSFileInfoSerializer()
             RegisterMember("ChunkSizeBytes", "chunkSize", new Int32Serializer());
             RegisterMember("ContentType", "contentType", new StringSerializer());
             RegisterMember("Filename", "filename", new StringSerializer());
+            RegisterMember("Id", "_id", ObjectIdSerializer.Instance);
             RegisterMember("IdAsBsonValue", "_id", BsonValueSerializer.Instance);
             RegisterMember("Length", "length", new Int64Serializer());
             RegisterMember("Metadata", "metadata", BsonDocumentSerializer.Instance);

tests/MongoDB.Driver.Tests/Linq/Linq3Implementation/Jira/CSharp5403Tests.cs

@@ -0,0 +1,75 @@
+/* Copyright 2010-present MongoDB 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 FluentAssertions;
+using MongoDB.Bson;
+using MongoDB.Driver.GridFS;
+using Xunit;
+
+namespace MongoDB.Driver.Tests.Linq.Linq3Implementation.Jira
+{
+    public class CSharp5403Tests : Linq3IntegrationTest
+    {
+        [Fact]
+        public void Project_Id_should_work()
+        {
+            var collection = GetCollection();
+
+            var find = collection
+                .Find(Builders<GridFSFileInfo>.Filter.Where(x => x.Id == ObjectId.Parse("111111111111111111111111")))
+                .Project(x => x.Id);
+
+            var filter = TranslateFindFilter(collection, find);
+            filter.Should().Be("{ _id : { $oid : '111111111111111111111111' } }");
+
+            var projection = TranslateFindProjection(collection, find);
+            projection.Should().Be("{ _id : 1 }");
+
+            var result = find.Single();
+            result.Should().Be(ObjectId.Parse("111111111111111111111111"));
+        }
+
+#pragma warning disable CS0618 // Type or member is obsolete
+        [Fact]
+        public void Project_IdAsBsonValue_should_work()
+        {
+            var collection = GetCollection();
+
+            var find = collection
+                .Find(Builders<GridFSFileInfo>.Filter.Where(x => x.IdAsBsonValue == new BsonObjectId(ObjectId.Parse("111111111111111111111111"))))
+                .Project(x => x.IdAsBsonValue);
+
+            var filter = TranslateFindFilter(collection, find);
+            filter.Should().Be("{ _id : { $oid : '111111111111111111111111' } }");
+
+            var projection = TranslateFindProjection(collection, find);
+            projection.Should().Be("{ _id : 1 }");
+
+            var result = find.Single();
+            result.Should().Be(ObjectId.Parse("111111111111111111111111"));
+        }
+#pragma warning restore CS0618 // Type or member is obsolete
+
+        private IMongoCollection<GridFSFileInfo> GetCollection()
+        {
+            var collection = GetCollection<GridFSFileInfo>("test");
+            CreateCollection(
+                collection.Database.GetCollection<BsonDocument>(collection.CollectionNamespace.CollectionName),
+                BsonDocument.Parse("{ _id : { $oid : '111111111111111111111111' }, filename : 'One' }"),
+                BsonDocument.Parse("{ _id : { $oid : '222222222222222222222222' }, filename : 'Two' }"));
+            return collection;
+        }
+    }
+}