CSHARP-5582: Assert unset BulkWriteException.partialResult in CRUD prose tests (#1727)

Author: sanych-sun

src/MongoDB.Driver/Core/Operations/ClientBulkWriteOperation.cs

@@ -210,7 +210,12 @@ private void EnsureCanProceedNextBatch(ConnectionId connectionId, BulkWriteRawRe
         {
             if (bulkWriteResult.TopLevelException != null)
             {
-                var partialResult = ToClientBulkWriteResult(bulkWriteResult);
+                ClientBulkWriteResult partialResult = null;
+                if (_writeModels.Offset != 0)
+                {
+                    partialResult = ToClientBulkWriteResult(bulkWriteResult);
+                }
+
                 throw new ClientBulkWriteException(
                     connectionId,
                     "An error occurred during bulkWrite operation. See InnerException for more details.",

tests/MongoDB.Driver.Tests/Specifications/crud/prose-tests/CrudProseTests.cs

@@ -496,6 +496,7 @@ public async Task MongoClient_bulkWrite_throws_if_no_operations_can_be_added_big
 
             var bulkWriteException = exception.Should().BeOfType<ClientBulkWriteException>().Subject;
             bulkWriteException.InnerException.Should().BeOfType<FormatException>();
+            bulkWriteException.PartialResult.Should().BeNull();
         }
 
         // https://github.com/mongodb/specifications/blob/7517681e6a3186cb7f3114314a9fe1bc3a747b9f/source/crud/tests/README.md?plain=1#L602
@@ -522,6 +523,7 @@ public async Task MongoClient_bulkWrite_throws_if_no_operations_can_be_added_big
 
             var bulkWriteException = exception.Should().BeOfType<ClientBulkWriteException>().Subject;
             bulkWriteException.InnerException.Should().BeOfType<FormatException>();
+            bulkWriteException.PartialResult.Should().BeNull();
         }
 
         // https://github.com/mongodb/specifications/blob/7517681e6a3186cb7f3114314a9fe1bc3a747b9f/source/crud/tests/README.md?plain=1#L647
@@ -560,6 +562,7 @@ public async Task MongoClient_bulkWrite_throws_if_auto_encryption_configured([Va
                 : Record.Exception(() => client.BulkWrite(models));
 
             exception.Should().BeOfType<NotSupportedException>();
+            exception.Message.Should().Be("BulkWrite does not currently support automatic encryption.");
         }
 
         // https://github.com/mongodb/specifications/blob/d1bdb68b7b4aec9681ea56d41c8b9a6c1a97d365/source/crud/tests/README.md?plain=1#L699