Skip WeightedAverage and MovingFunction aggregations on < 6.4.0

Author: russcam

src/Tests/Tests/Aggregations/Bucket/Composite/CompositeAggregationUsageTests.cs

@@ -190,8 +190,11 @@ protected override void ExpectResponse(ISearchResponse<Project> response)
 				var nested = item.Nested("project_tags");
 				nested.Should().NotBeNull();
 
-				var nestedTerms = nested.Terms("tags");
-				nestedTerms.Buckets.Count.Should().BeGreaterThan(0);
+				if (nested.DocCount > 0)
+				{
+					var nestedTerms = nested.Terms("tags");
+					nestedTerms.Buckets.Count.Should().BeGreaterThan(0);
+				}
 			}
 		}
 	}

src/Tests/Tests/Aggregations/Metric/WeightedAverage/WeightedAverageAggregationUsageTests.cs

@@ -1,4 +1,5 @@
 using System;
+using Elastic.Xunit.XunitPlumbing;
 using FluentAssertions;
 using Nest;
 using Tests.Framework.Integration;
@@ -17,8 +18,11 @@ namespace Tests.Aggregations.Metric.WeightedAverage
 	 * value. Weighted averages, on the other hand, weight each datapoint differently. The amount that each
 	 * datapoint contributes to the final value is extracted from the document, or provided by a script.
 	 *
+	 * NOTE: Only available in Elasticsearch 6.4.0+
+	 *
 	 * Be sure to read the Elasticsearch documentation on {ref_current}/search-aggregations-metrics-weight-avg-aggregation.html[Weighted Avg Aggregation]
 	 */
+	[SkipVersion("<6.4.0", "Introduced in Elasticsearch 6.4.0+")]
 	public class WeightedAverageAggregationUsageTests : AggregationUsageTestBase
 	{
 		public WeightedAverageAggregationUsageTests(ReadOnlyCluster i, EndpointUsage usage) : base(i, usage) { }

src/Tests/Tests/Aggregations/Pipeline/MovingFunction/MovingFunctionAggregationUsageTests.cs

@@ -11,6 +11,18 @@
 
 namespace Tests.Aggregations.Pipeline.MovingFunction
 {
+	/**
+	 * Given an ordered series of data, the Moving Function aggregation will slide a window across the data and allow
+	 * the user to specify a custom script that is executed on each window of data. For convenience, a number of
+	 * common functions are predefined such as min/max, moving averages, etc.
+	 *
+     * This is conceptually very similar to the Moving Average pipeline aggregation, except it provides more functionality.
+	 *
+	 * NOTE: Only available in Elasticsearch 6.4.0+
+	 *
+	 * Be sure to read the Elasticsearch documentation on {ref_current}/search-aggregations-pipeline-movfn-aggregation.html[Moving Function Aggregation]
+	 */
+	[SkipVersion("<6.4.0", "Introduced in Elasticsearch 6.4.0+")]
 	public class MovingFunctionAggregationUsageTests : AggregationUsageTestBase
 	{
 		public MovingFunctionAggregationUsageTests(ReadOnlyCluster cluster, EndpointUsage usage) : base(cluster, usage) { }