Add support for span multi term query.

Closes #863.

Author: gmarz

Diff for: src/Nest/DSL/Query/IQueryContainer.cs

@@ -125,6 +125,9 @@ public interface IQueryContainer : ICustomJson
 		[JsonProperty(PropertyName = "span_not")]
 		ISpanNotQuery SpanNot { get; set; }
 
+		[JsonProperty(PropertyName = "span_multi")]
+		ISpanMultiTermQuery SpanMultiTerm { get; set; }
+
 		[JsonProperty(PropertyName = "top_children")]
 		ITopChildrenQuery TopChildren { get; set; }
 

Diff for: src/Nest/DSL/Query/QueryContainer.cs

@@ -77,6 +77,8 @@ public class QueryContainer : IQueryContainer
 
 		ISpanNearQuery IQueryContainer.SpanNear { get; set; }
 
+		ISpanMultiTermQuery IQueryContainer.SpanMultiTerm { get; set; }
+
 		ITopChildrenQuery IQueryContainer.TopChildren { get; set; }
 
 		INestedQuery IQueryContainer.Nested { get; set; }

Diff for: src/Nest/DSL/Query/QueryDescriptor.cs

@@ -819,6 +819,19 @@ public QueryContainer SpanNot(Action<SpanNotQuery<T>> selector)
 			return this.New(span, q => q.SpanNot = span);
 		}
 
+		/// <summary>
+		/// Wrap a multi term query (one of fuzzy, prefix, term range or regexp query) 
+		/// as a span query so it can be nested.
+		/// </summary>
+		public QueryContainer SpanMultiTerm(Action<SpanMultiTermQueryDescriptor<T>> selector)
+		{
+			selector.ThrowIfNull("selector");
+			var span = new SpanMultiTermQueryDescriptor<T>();
+			selector(span);
+
+			return this.New(span, q => q.SpanMultiTerm = span);
+		}
+
 		/// <summary>
 		/// custom_score query allows to wrap another query and customize the scoring of it optionally with a 
 		/// computation derived from other field values in the doc (numeric ones) using script or boost expression

Diff for: src/Nest/DSL/Query/SpanMultiTermQueryDescriptor.cs

@@ -0,0 +1,42 @@
+using Newtonsoft.Json;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace Nest
+{
+	[JsonObject(MemberSerialization = MemberSerialization.OptIn)]
+	public interface ISpanMultiTermQuery : ISpanSubQuery
+	{
+		[JsonProperty("match")]
+		IQueryContainer Match { get; set; }
+	}
+
+	public class SpanMultiTermQuery : PlainQuery, ISpanMultiTermQuery
+	{
+		protected override void WrapInContainer(IQueryContainer container)
+		{
+			container.SpanMultiTerm = this;
+		}
+
+		public IQueryContainer Match { get; set; }
+
+		public bool IsConditionless { get { return false; } }
+	}
+
+	public class SpanMultiTermQueryDescriptor<T> : ISpanMultiTermQuery
+		where T : class
+	{
+		IQueryContainer ISpanMultiTermQuery.Match { get; set; }
+
+		bool IQuery.IsConditionless { get { return false; } }
+
+		public SpanMultiTermQueryDescriptor<T> Match(Func<QueryDescriptor<T>, QueryContainer> querySelector)
+		{
+			var q = new QueryDescriptor<T>();
+			((ISpanMultiTermQuery)this).Match = querySelector(q);
+			return this;
+		}
+	}
+}

Diff for: src/Nest/DSL/Query/SpanQueryDescriptor.cs

@@ -25,6 +25,9 @@ public interface ISpanQuery : IQuery
 
 		[JsonProperty(PropertyName = "span_not")]
 		ISpanNotQuery SpanNot { get; set; }
+
+		[JsonProperty(PropertyName = "span_multi")]
+		ISpanMultiTermQuery SpanMultiTerm { get; set; }
 	}
 
 	public class SpanQuery : ISpanQuery
@@ -35,6 +38,7 @@ public class SpanQuery : ISpanQuery
 		public ISpanNearQuery SpanNear { get; set; }
 		public ISpanOrQuery SpanOr { get; set; }
 		public ISpanNotQuery SpanNot { get; set; }
+		public ISpanMultiTermQuery SpanMultiTerm { get; set; }
 	}
 
 	public class SpanQuery<T> : ISpanQuery where T : class
@@ -49,6 +53,8 @@ public class SpanQuery<T> : ISpanQuery where T : class
 
 		ISpanNotQuery ISpanQuery.SpanNot { get; set; }
 
+		ISpanMultiTermQuery ISpanQuery.SpanMultiTerm { get; set; }
+
 		bool IQuery.IsConditionless
 		{
 			get
@@ -59,7 +65,8 @@ bool IQuery.IsConditionless
 					((ISpanQuery)this).SpanFirst as IQuery,
 					((ISpanQuery)this).SpanNear as IQuery,
 					((ISpanQuery)this).SpanOr as IQuery,
-					((ISpanQuery)this).SpanNot as IQuery
+					((ISpanQuery)this).SpanNot as IQuery,
+					((ISpanQuery)this).SpanMultiTerm as IQuery
 				};
 				return queries.All(q => q == null || q.IsConditionless);
 			}
@@ -117,6 +124,12 @@ public SpanQuery<T> SpanNot(Func<SpanNotQuery<T>, SpanNotQuery<T>> selector)
 			var q = selector(new SpanNotQuery<T>());
 			return CreateQuery(q, (sq) => ((ISpanQuery)sq).SpanNot = q);
 		}
+		public SpanQuery<T> SpanMultiTerm(Func<SpanMultiTermQueryDescriptor<T>, SpanMultiTermQueryDescriptor<T>> selector)
+		{
+			selector.ThrowIfNull("selector");
+			var q= selector(new SpanMultiTermQueryDescriptor<T>());
+			return CreateQuery(q, (sq) => ((ISpanQuery)sq).SpanMultiTerm = q);
+		}
 
 		private SpanQuery<T> CreateQuery<K>(K query, Action<SpanQuery<T>> setProperty) where K : ISpanSubQuery
 		{

Diff for: src/Nest/Domain/DSL/Query.cs

@@ -205,6 +205,11 @@ public static QueryContainer SpanTerm(string field, string value, double? Boost
 			return new QueryDescriptor<T>().SpanTerm(field, value, Boost);
 		}
 
+		public static QueryContainer SpanMultiTerm(Action<SpanMultiTermQueryDescriptor<T>> selector)
+		{
+			return new QueryDescriptor<T>().SpanMultiTerm(selector);
+		}
+
 		public static QueryContainer Term<K>(Expression<Func<T, K>> fieldDescriptor, K value, double? Boost = null)
 		{
 			return new QueryDescriptor<T>().Term(fieldDescriptor, value, Boost);

Diff for: src/Nest/Nest.csproj

@@ -170,6 +170,7 @@
     <Compile Include="DSL\MultiPercolateDescriptor.cs" />
     <Compile Include="DSL\Paths\IndexOptionalNamePathDescriptor.cs" />
     <Compile Include="DSL\Paths\IndicesOptionalTypesNamePathDecriptor.cs" />
+    <Compile Include="DSL\Query\SpanMultiTermQueryDescriptor.cs" />
     <Compile Include="DSL\TypeExistsDescriptor.cs" />
     <Compile Include="DSL\Query\Functions\FieldValueFactorDescriptor.cs" />
     <Compile Include="DSL\Query\GeoShapeMultiPointQueryDescriptor.cs" />

Diff for: src/Tests/Nest.Tests.Integration/Nest.Tests.Integration.csproj

@@ -172,6 +172,7 @@
     <Compile Include="Search\Filter\PrefixFilterTests.cs" />
     <Compile Include="Search\Filter\RangeFilterTests.cs" />
     <Compile Include="Search\Query\BoolQueryResults.cs" />
+    <Compile Include="Search\Query\SpanQueryTests.cs" />
     <Compile Include="Search\Query\TermToString.cs" />
     <Compile Include="Core\UpdateTests.cs" />
     <Compile Include="Search\Filter\BoolFilterTests.cs" />

Diff for: src/Tests/Nest.Tests.Integration/Search/Query/SpanQueryTests.cs

@@ -0,0 +1,34 @@
+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.Search.Query
+{
+	[TestFixture]
+	public class SpanQueryTests : IntegrationTests
+	{
+		[Test]
+		public void SpanMultiTermQuery()
+		{
+			var r = Client.Search<ElasticsearchProject>(s => s
+				.Query(q => q
+					.SpanMultiTerm(sp => sp
+						.Match(m => m
+							.Prefix(p => p
+								.OnField(ep => ep.Name)
+								.Value("NEST")
+							)
+						)
+					)
+				)
+			);
+
+			r.IsValid.Should().BeTrue();
+		}
+	}
+}

Diff for: src/Tests/Nest.Tests.Unit/Nest.Tests.Unit.csproj

@@ -398,6 +398,7 @@
     <Compile Include="Search\Query\Singles\HasParentQueryJson.cs" />
     <Compile Include="Search\Query\Singles\MultiMatch\MultiMatchJson.cs" />
     <Compile Include="Search\Query\Modes\QueryModesTests.cs" />
+    <Compile Include="Search\Query\Singles\SpanMultiTermQueryJson.cs" />
     <Compile Include="Search\Query\Singles\Term\TermToStringJson.cs" />
     <Compile Include="Search\Rescoring\RescoreTests.cs" />
     <Compile Include="Search\Facets\DateHistogramFacetJson.cs" />

Diff for: src/Tests/Nest.Tests.Unit/Search/Query/Singles/SpanMultiTermQueryJson.cs

@@ -0,0 +1,42 @@
+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.Unit.Search.Query.Singles
+{
+	[TestFixture]
+	public class SpanMultiTermQueryJson : BaseJsonTests
+	{
+		[Test]
+		public void SpanMultiTermQuery()
+		{
+			var s = new SearchDescriptor<ElasticsearchProject>()
+				.From(0)
+				.Size(10)
+				.Query(q => q
+					.SpanMultiTerm(sp => sp
+						.Match(m => m
+							.Prefix(p => p
+								.OnField(ep => ep.Name)
+								.Value("NEST")
+							)
+						)
+					)
+				);
+			var json = TestElasticClient.Serialize(s);
+			var expected = @"{ from: 0, size: 10, query : 
+			{
+				span_multi:{
+					match:{
+						prefix : { name :  { value : ""NEST"" } }
+					}
+				}
+			}}";
+			Assert.True(json.JsonEquals(expected), json);
+		}
+	}
+}