CSHARP-797: Throw an exception if a bulk operation is empty or Execute is called more than once.

Author: rstam

MongoDB.Driver/MongoCollection.cs

@@ -190,6 +190,15 @@ public virtual CommandResult AggregateExplain(AggregateArgs args)
         /// </returns>
         public virtual BulkWriteResult BulkWrite(BulkWriteArgs args)
         {
+            if (args == null)
+            {
+                throw new ArgumentNullException("args");
+            }
+            if (args.Requests == null)
+            {
+                throw new ArgumentNullException("args.Requests");
+            }
+
             var connection = _server.AcquireConnection(ReadPreference.Primary);
             try
             {

MongoDB.Driver/Operations/BulkMixedWriteOperation.cs

@@ -79,8 +79,11 @@ public BulkWriteResult Execute(MongoConnection connection)
             var remainingRequests = Enumerable.Empty<WriteRequest>();
             var hasWriteErrors = false;
 
+            var runCount = 0;
             foreach (var run in FindRuns())
             {
+                runCount++;
+
                 if (hasWriteErrors && _isOrdered)
                 {
                     remainingRequests = remainingRequests.Concat(run.Requests);
@@ -93,6 +96,11 @@ public BulkWriteResult Execute(MongoConnection connection)
                 hasWriteErrors |= batchResult.HasWriteErrors;
             }
 
+            if (runCount == 0)
+            {
+                throw new InvalidOperationException("Bulk write operation is empty.");
+            }
+
             var combiner = new BulkWriteBatchResultCombiner(batchResults, _writeConcern.Enabled);
             return combiner.CreateResultOrThrowIfHasErrors(remainingRequests);
         }

MongoDB.Driver/Operations/BulkWriteOperation.cs

@@ -27,6 +27,7 @@ public sealed class BulkWriteOperation
         private readonly MongoCollection _collection;
         private readonly bool _isOrdered;
         private readonly List<WriteRequest> _requests = new List<WriteRequest>();
+        private bool _hasAlreadyBeenExecuted;
 
         // constructors
         internal BulkWriteOperation(MongoCollection collection, bool isOrdered)
@@ -42,6 +43,12 @@ internal BulkWriteOperation(MongoCollection collection, bool isOrdered)
         /// <returns>A BulkWriteResult.</returns>
         public BulkWriteResult Execute()
         {
+            if (_hasAlreadyBeenExecuted)
+            {
+                throw new InvalidOperationException("A bulk write operation can only be executed once.");
+            }
+            _hasAlreadyBeenExecuted = true;
+
             var args = new BulkWriteArgs
             {
                 IsOrdered = _isOrdered,

MongoDB.DriverUnitTests/MongoCollectionTests.cs

@@ -246,6 +246,23 @@ public void TestBulkDelete()
             Assert.AreEqual(2, _collection.FindOne()["x"].ToInt32());
         }
 
+        [Test]
+        public void TestBulkEmpty()
+        {
+            var bulk = _collection.InitializeOrderedBulkOperation();
+            Assert.Throws<InvalidOperationException>(() => bulk.Execute());
+        }
+
+        [Test]
+        public void TestBulkExecuteTwice()
+        {
+            _collection.Drop();
+            var bulk = _collection.InitializeOrderedBulkOperation();
+            bulk.Insert(new BsonDocument());
+            bulk.Execute();
+            Assert.Throws<InvalidOperationException>(() => bulk.Execute());
+        }
+
         [Test]
         public void TestBulkInsert()
         {
@@ -264,19 +281,6 @@ public void TestBulkInsert()
             Assert.AreEqual(3, _collection.Count());
         }
 
-        [Test]
-        public void TestBulkInsertZeroDocuments()
-        {
-            if (_primary.BuildInfo.Version >= new Version(2, 5, 5))
-            {
-                _collection.Drop();
-                var result = _collection.BulkWrite(
-                    new BulkWriteArgs { WriteConcern = WriteConcern.Acknowledged });
-
-                Assert.AreEqual(0, _collection.Count());
-            }
-        }
-
         [Test]
         public void TestBulkUpdate()
         {