CSHARP-732: fixed linq predicate not working with types derived from ICollection<T>

Author: craiggwilson

MongoDB.Driver/Linq/Translators/PredicateTranslator.cs

@@ -627,7 +627,7 @@ private IMongoQuery BuildInQuery(MethodCallExpression methodCallExpression)
                     methodDeclaringType = methodDeclaringType.GetGenericTypeDefinition();
                 }
 
-                bool contains = methodDeclaringType.GetInterface("ICollection`1") != null;
+                bool contains = methodDeclaringType == typeof(ICollection<>) || methodDeclaringType.GetInterface("ICollection`1") != null;
                 if (contains && arguments.Length == 1)
                 {
                     serializationInfo = _serializationInfoHelper.GetSerializationInfo(arguments[0]);

MongoDB.DriverUnitTests/Linq/SelectQueryTests.cs

@@ -2065,6 +2065,32 @@ where local.Contains(c.X)
             Assert.AreEqual(3, Consume(query));
         }
 
+        [Test]
+        public void TestWhereLocalIListContainsX()
+        {
+            // this will generate a non-list, non-array.
+            IList<int> local = new[] { 1, 2, 3 };
+
+            var query = from c in _collection.AsQueryable<C>()
+                        where local.Contains(c.X)
+                        select c;
+
+            var translatedQuery = MongoQueryTranslator.Translate(query);
+            Assert.IsInstanceOf<SelectQuery>(translatedQuery);
+            Assert.AreSame(_collection, translatedQuery.Collection);
+            Assert.AreSame(typeof(C), translatedQuery.DocumentType);
+
+            var selectQuery = (SelectQuery)translatedQuery;
+            Assert.AreEqual("(C c) => Int32[]:{ 1, 2, 3 }.Contains(c.X)", ExpressionFormatter.ToString(selectQuery.Where));
+            Assert.IsNull(selectQuery.OrderBy);
+            Assert.IsNull(selectQuery.Projection);
+            Assert.IsNull(selectQuery.Skip);
+            Assert.IsNull(selectQuery.Take);
+
+            Assert.AreEqual("{ \"x\" : { \"$in\" : [1, 2, 3] } }", selectQuery.BuildQuery().ToJson());
+            Assert.AreEqual(3, Consume(query));
+        }
+
         [Test]
         public void TestWhereAContains2()
         {