re #880 - Ensures that a nested filter consisting of only a filter does not result in a conditionless NEST filter (leading to its exclusion from generated json query)

Author: Philo

src/Nest/DSL/Filter/NestedFilterDescriptor.cs

@@ -59,9 +59,12 @@ public class NestedFilterDescriptor<T> : FilterBase, INestedFilter where T : cla
 		bool IFilter.IsConditionless
 		{
 			get
-			{
-				return ((INestedFilter)this).Query == null 
-					|| ((INestedFilter)this).Query.IsConditionless;
+			{
+				return (((INestedFilter)this).Query == null 
+					|| ((INestedFilter)this).Query.IsConditionless)
+                    && (((INestedFilter)this).Filter == null
+                    || ((INestedFilter)this).Filter.IsConditionless)
+                    ;
 			}
 		}
 

src/Tests/Nest.Tests.Unit/Search/Filter/ConditionLess/ConditionLessTests.cs

@@ -28,6 +28,7 @@ private void DoConditionlessFilter(Func<FilterDescriptor<ElasticsearchProject>,
 
 			this.JsonEquals(s, System.Reflection.MethodInfo.GetCurrentMethod(), "MatchAll");
 		}
+
 		private void DoNonConditionlessFilter(Func<FilterDescriptor<ElasticsearchProject>, FilterContainer> filter)
 		{
 			var s = new SearchDescriptor<ElasticsearchProject>()
@@ -146,8 +147,12 @@ public void MissingTest()
 		public void NestedTest()
 		{
 			this.DoConditionlessFilter(f => f.Nested(nf=>nf.Query(q=>q.Term(string.Empty, string.Empty))));
-			this.DoConditionlessFilter(f => f.Nested(null));
-		}
+			this.DoConditionlessFilter(f => f.Nested(null));
+            this.DoConditionlessFilter(f => f.Nested(nf => nf.Filter(q => q.Term(string.Empty, string.Empty))));
+
+            this.DoNonConditionlessFilter(f => f.Nested(nf => nf.Query(q => q.Term("myfield", "myvalue"))));
+            this.DoNonConditionlessFilter(f => f.Nested(nf => nf.Filter(q => q.Term("myfield", "myvalue"))));
+        }
 
 
 		[Test]