Fix #1217: add matched_queries to search response

Author: gmarz

src/Nest/Domain/Hit/Hit.cs

@@ -16,11 +16,10 @@ public interface IHit<out T> where T : class
 		string Type { get; }
 		string Version { get; }
 		string Id { get; }
-
 		IEnumerable<object> Sorts { get; }
-
 		HighlightFieldDictionary Highlights { get; }
 		Explanation Explanation { get; }
+		IEnumerable<string> MatchedQueries { get; }
 	}
 
 	[JsonObject]
@@ -76,5 +75,7 @@ public HighlightFieldDictionary Highlights
 		[JsonProperty(PropertyName = "_explanation")]
 		public Explanation Explanation { get; internal set; }
 
+		[JsonProperty(PropertyName = "matched_queries")]
+		public IEnumerable<string> MatchedQueries { get; internal set; }
 	}
 }

src/Tests/Nest.Tests.Integration/Search/NamedFilter/NamedFilterTests.cs

@@ -1,4 +1,5 @@
-using System.Linq;
+using FluentAssertions;
+using System.Linq;
 using Nest.Tests.MockData;
 using Nest.Tests.MockData.Domain;
 using NUnit.Framework;
@@ -22,11 +23,12 @@ public void SimpleNamedFilter()
 					|| f.Name("myfilter2").Terms(p => p.Name.Suffix("sort"), new[] {"nest"})
 				)
 				);
-			Assert.True(queryResults.IsValid);
-			//Assert.True(queryResults.Documents.Any());
-			//Assert matched_filters is returned
-			//Possible ES bug
-			//https://github.com/elasticsearch/elasticsearch/issues/3097
+			queryResults.IsValid.Should().BeTrue();
+			foreach(var hit in queryResults.Hits)
+			{
+				hit.MatchedQueries.Should().NotBeNull().And.NotBeEmpty();
+				hit.MatchedQueries.Any(mq => mq.Contains("myfilter") || mq.Contains("myfilter2"));
+			}
 		}
 	}