-
Type:
Bug
-
Resolution: Unresolved
-
Priority:
Major - P3
-
None
-
Affects Version/s: 2.9.1
-
Component/s: Serialization
-
None
Not sure if this is intended, but the anonymous-type based full-document projection respects the Bson[Class]Map settings, while the partial projection does not. In the following example the "Value" field of the "Data" class default is set to -1. When projecting the full document, the full serializer is used and the projected value is -1. When really proecting fields, the default (0) is used. This can bring nasty surprises because full-document projection can be used when the projection expression references document object itself, so changing the projected fields could influence the value of the other, non-projected fields.
private class Data
{
[Bson.Serialization.Attributes.BsonDefaultValue(-1)]
public int A { get; set; }
}
[Fact]
public void Should_produce_serializer_that_respects_bson_map()
{
var data = ProjectData(x => x, "{}");
data.A.Should().Be(-1);
}
[Fact]
public void Should_produce_serializer_that_respects_bson_map_when_projecting()
{
var data = ProjectData(x => new { x.A }, "{}");
data.A.Should().Be(-1);
}
private T ProjectData<T>(Expression<Func<Data, T>> projector, string json)
{
var serializer = BsonSerializer.SerializerRegistry.GetSerializer<Data>();
var projectionInfo = FindProjectionTranslator.Translate<Data, T>(projector, serializer, BsonSerializer.SerializerRegistry);
using (var reader = new JsonReader(json))
{
var context = BsonDeserializationContext.CreateRoot(reader);
return projectionInfo.ProjectionSerializer.Deserialize(context);
}
}