Adding test in attempt to reproduce #1079

Author: gmarz

src/Tests/Nest.Tests.Integration/Nest.Tests.Integration.csproj

@@ -182,6 +182,7 @@
     <Compile Include="Core\AsyncTests.cs" />
     <Compile Include="Mapping\MappingVisitorTests.cs" />
     <Compile Include="Mapping\GetMultipleMappingTests.cs" />
+    <Compile Include="Reproduce\Reproduce1079Tests.cs" />
     <Compile Include="Reproduce\Reproduce769Tests.cs" />
     <Compile Include="Reproduce\Reproduce945Tests.cs" />
     <Compile Include="Reproduce\Reproduce953Tests.cs" />

src/Tests/Nest.Tests.Integration/Reproduce/Reproduce1079Tests.cs

@@ -0,0 +1,39 @@
+using FluentAssertions;
+using Nest.Tests.MockData.Domain;
+using NUnit.Framework;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Nest.Tests.Integration.Reproduce
+{
+	[TestFixture]
+	public class Reproduce1079Tests : IntegrationTests
+	{
+		[Test]
+		public void InnerSumAggregationTest()
+		{
+			var response = this.Client.Search<ElasticsearchProject>(s => s
+				.Aggregations(a => a
+					.Histogram("hist", h => h
+						.Field(p => p.StartedOn)
+						.Interval(3000)
+						.Aggregations(aa => aa
+							.Sum("sizes", sa => sa
+								.Field(p => p.LongValue)
+							)
+						)
+					)
+				)
+			);
+
+			var hist = response.Aggs.Histogram("hist");
+			foreach (var interval in hist.Items)
+			{
+				var sizes = interval.Sum("sizes");
+			}
+		}
+	}
+}