Fix #1253: terms filter/query should also work on IEnumerable field

Author: gmarz

src/Nest/DSL/Filter/FilterDescriptor.cs

@@ -731,8 +731,6 @@ public FilterContainer Term(Expression<Func<T, object>> fieldDescriptor, object
 		/// </summary>
 		public FilterContainer Term(string field, object term)
 		{
-
-
 			ITermFilter filter = new TermFilterDescriptor();
 			filter.Field = field;
 			filter.Value = term;
@@ -749,8 +747,20 @@ public FilterContainer Terms<K>(Expression<Func<T, K>> fieldDescriptor, IEnumera
 			filter.Terms = (terms != null) ? terms.Cast<object>() : null;
 			filter.Execution = Execution;
 			return this.New(filter, f=>f.Terms = filter);
-		}	
-		
+		}
+
+		/// <summary>
+		/// Filters documents that have fields that match any of the provided terms (not analyzed). 
+		/// </summary>
+		public FilterContainer Terms<K>(Expression<Func<T, IEnumerable<K>>> fieldDescriptor, IEnumerable<K> terms, TermsExecution? Execution = null)
+		{
+			ITermsFilter filter = new TermsFilterDescriptor();
+			filter.Field = fieldDescriptor;
+			filter.Terms = (terms != null) ? terms.Cast<object>() : null;
+			filter.Execution = Execution;
+			return this.New(filter, f => f.Terms = filter);
+		}
+
 		/// <summary>
 		/// Filters documents that have fields that match any of the provided terms (not analyzed). 
 		/// </summary>

src/Nest/DSL/Query/QueryDescriptor.cs

@@ -126,6 +126,19 @@ public QueryContainer Terms<K>(Expression<Func<T, K>> objectPath, IEnumerable<K>
 				.Terms(terms)
 			);
 		}
+		
+		/// <summary>
+		/// A query that match on any (configurable) of the provided terms. This is a simpler syntax query for using a bool query with several term queries in the should clauses.
+		/// </summary>
+		public QueryContainer Terms<K>(Expression<Func<T, IEnumerable<K>>> objectPath, IEnumerable<K> terms)
+		{
+			PropertyPathMarker field = objectPath;
+			return this.TermsDescriptor<K>(t => t
+				.OnField(field)
+				.Terms(terms)
+			);
+		}
+
 		/// <summary>
 		/// A query that match on any (configurable) of the provided terms. This is a simpler syntax query for using a bool query with several term queries in the should clauses.
 		/// </summary>

src/Nest/DSL/Query/TermsQueryDescriptor.cs

@@ -73,6 +73,12 @@ public TermsQueryDescriptor<T, K> OnField(string field)
 			return this;
 		}
 
+		public TermsQueryDescriptor<T, K> OnField(PropertyPathMarker field)
+		{
+			((ITermsQuery)this).Field = field;
+			return this;
+		}
+
 		public TermsQueryDescriptor<T, K> OnField(Expression<Func<T, K>> objectPath)
 		{
 			((ITermsQuery)this).Field = objectPath;