tried to reproduce #2136, 2.x (latest stable release does not have number_of_replica update index settings bug that I just fixed in master (5.x)

Author: Mpdreamz

src/Tests/Indices/IndexSettings/GetIndexSettings/GetIndexSettingsApiTests.cs

@@ -1,5 +1,7 @@
 using System;
+using System.Linq;
 using Elasticsearch.Net;
+using FluentAssertions;
 using Nest;
 using Tests.Framework;
 using Tests.Framework.Integration;
@@ -33,5 +35,14 @@ protected override LazyResponses ClientUsage() => Calls(
 		{
 			Local = true
 		};
+
+		protected override void ExpectResponse(IGetIndexSettingsResponse response)
+        {
+            response.Indices.Should().NotBeEmpty();
+            var index = response.Indices.First().Value;
+            index.Should().NotBeNull();
+            index.Settings.NumberOfShards.Should().HaveValue().And.BeGreaterThan(0);
+            index.Settings.NumberOfReplicas.Should().HaveValue();
+        }
 	}
-}
+}

src/Tests/Indices/IndexSettings/UpdateIndicesSettings/UpdateIndexSettingsApiTests.cs

@@ -27,20 +27,23 @@ protected override LazyResponses ClientUsage() => Calls(
 
 		protected override object ExpectJson { get; } = new Dictionary<string, object>
 		{
-			{ "index.blocks.write", false }
+			{ "index.blocks.write", false },
+			{ "index.number_of_replicas", 2 }
 		};
 
 		protected override Func<UpdateIndexSettingsDescriptor, IUpdateIndexSettingsRequest> Fluent => d => d
 			.IndexSettings(i => i
 				.BlocksWrite(false)
+				.NumberOfReplicas(2)
 			);
 
 		protected override UpdateIndexSettingsRequest Initializer => new UpdateIndexSettingsRequest
 		{
 			IndexSettings = new Nest.IndexSettings
 			{
-				BlocksWrite = false
+				BlocksWrite = false,
+				NumberOfReplicas = 2
 			}
 		};
 	}
-}
+}