for consistency: change behaviour regarding present-but-null

values in MongoDBObject#get. If the value is present and null, the method will now return Some(None), if it is not present, it will return None.

Author: mberndt123

casbah-commons/src/main/scala/MongoDBObject.scala

@@ -91,12 +91,11 @@ class MongoDBObject(val underlying: DBObject = new BasicDBObject) extends mutabl
  }
  }
 
- // scalastyle:off null
- override def get(key: String): Option[AnyRef] = underlying.get(key) match {
- case null => None
- case value => Some(value)
- }
- // scalastyle:on null
+ override def get(key: String): Option[AnyRef] =
+ /* underlying.get returns null both when the value is missing and when
+ * it is null. Unlike nulls, Options can be nested, so we can allow clients
+ * to see the difference. */
+ Option(underlying.get(key)).orElse(if (containsField(key)) Some(None) else None)
 
  // scalastyle:off method.name
  def ++(pairs: (String, Any)*): DBObject = {
@@ -170,6 +169,7 @@ class MongoDBObject(val underlying: DBObject = new BasicDBObject) extends mutabl
  case (tryObj, n) =>
  tryObj.flatMap(obj => Try(obj.get(n).get.asInstanceOf[DBObject]))
  }
+
  val res = tryLeaf.flatMap(obj => Try(obj.get(path.last).get.asInstanceOf[A])) match {
  case Success(list: BasicDBList) => Some(new MongoDBList(list))
  case Success(x) => Some(x)

casbah-query/src/test/scala/DSLCoreOperatorsSpec.scala

@@ -155,7 +155,7 @@ class DSLCoreOperatorsSpec extends CasbahMutableSpecification {
  timeQuery must haveEntry("foo.$ne" -> timestamp)
  }
 
- "Accept a right hand value of None" in skipped {
+ "Accept a right hand value of None" in {
  val neQuery = "foo" $ne None
  neQuery must haveEntry("foo.$ne" -> None)
  }