added an example to illustrate #1240

Author: Mpdreamz

src/Tests/Nest.Tests.Unit/Core/Update/UpdateTests.cs

@@ -1,17 +1,29 @@
 using System.Reflection;
 using NUnit.Framework;
 using Nest.Tests.MockData.Domain;
+using Newtonsoft.Json;
 
 namespace Nest.Tests.Unit.Core.Update
 {
 	[TestFixture]
 	public class UpdateTests : BaseJsonTests
 	{
-		public class PartialElasticSearchProject
+		public class PartialElasticsearchProject
 		{
 			public string Name { get; set; }
 			public string Country { get; set; }
 		}
+		
+		/// <summary>
+		/// This POCO models an ElasticsearchProject that allows country to serialize to null explicitly
+		/// So that we can use it to clear contents in the Update API
+		/// </summary>
+		public class PartialElasticsearchProjectWithNull
+		{
+			[JsonProperty(NullValueHandling = NullValueHandling.Include)]
+			public string Country { get; set; }
+		}
+
 		public class UpsertCount
 		{
 			public int Count { get; set; }
@@ -26,8 +38,9 @@ public void UpsertUsingScript()
 				  .Add("count", 4)
 			  )
 			  .Upsert(new UpsertCount { Count = 1 }); 
-			this.JsonEquals(s, MethodInfo.GetCurrentMethod()); 
+			this.JsonEquals(s, MethodBase.GetCurrentMethod()); 
 		}
+
 		[Test]
 		public void UpsertUsingScriptAndPartialObject()
 		{
@@ -38,20 +51,33 @@ public void UpsertUsingScriptAndPartialObject()
 			  )
 			  .Upsert(new { count = 4});
 
-			this.JsonEquals(s, MethodInfo.GetCurrentMethod());
+			this.JsonEquals(s, MethodBase.GetCurrentMethod());
 		}
 
 		[Test]
 		public void UpdateUsingPartial()
 		{
 			var originalProject = new ElasticsearchProject { Id = 1, Name = "NeST", Country = "UK" };
-			var partialUpdate = new PartialElasticSearchProject { Name = "NEST", Country = "Netherlands" };
+			var partialUpdate = new PartialElasticsearchProject { Name = "NEST", Country = "Netherlands" };
+
+			var s = new UpdateDescriptor<ElasticsearchProject, PartialElasticsearchProject>()
+				.IdFrom(originalProject) //only used to infer the id
+				.Doc(partialUpdate); //the actual partial update statement;
+
+			this.JsonEquals(s, MethodBase.GetCurrentMethod());
+		}
+
+		[Test]
+		public void UpdateUsingPartialWithNull()
+		{
+			var originalProject = new ElasticsearchProject { Id = 1, Name = "NEST", Country = "UK" };
+			var partialUpdate = new PartialElasticsearchProjectWithNull { Country = null };
 
-			var s = new UpdateDescriptor<ElasticsearchProject, PartialElasticSearchProject>()
+			var s = new UpdateDescriptor<ElasticsearchProject, PartialElasticsearchProjectWithNull>()
 				.IdFrom(originalProject) //only used to infer the id
 				.Doc(partialUpdate); //the actual partial update statement;
 
-			this.JsonEquals(s, MethodInfo.GetCurrentMethod());
+			this.JsonEquals(s, MethodBase.GetCurrentMethod());
 		}
 
 	}

src/Tests/Nest.Tests.Unit/Core/Update/UpdateUsingPartialWithNull.json

@@ -0,0 +1,5 @@
+  {
+  "doc": {
+    "country": null
+  }
+}

src/Tests/Nest.Tests.Unit/Nest.Tests.Unit.csproj

@@ -674,6 +674,9 @@
     <None Include="Core\UpdateSettings\CanSpecifyNewAnalysisSettings.json">
       <CopyToOutputDirectory>Always</CopyToOutputDirectory>
     </None>
+    <None Include="Core\Update\UpdateUsingPartialWithNull.json">
+      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+    </None>
     <None Include="Core\Update\UpsertUsingScriptAndPartialObject.json">
       <CopyToOutputDirectory>Always</CopyToOutputDirectory>
     </None>