NullPointerException in Bulk Copy

[typhoon2k]

Driver version

12.6.3/12.7.0

SQL Server version

SQL Server 2019

Client Operating System

Any

JAVA/JVM version

11.0.23

Table schema

Any table schema with SQLVariant column.

Problem description

Bulk Copy is performed using prepared statement and useBulkCopyForBatchInsert=true in connection string.
Getting null pointer exception, if destination table has SQLVariant column.

It seems that SQLServerBulkCopy.writeSqlVariant expects sourceResultSet to be set, but when void writeToServer(ISQLServerBulkData sourceData) is called this variable is explicitly set to null.
I guess it never worked with SQLVariant columns in target table.

Expected behavior

Bulk copy operation should be successful.

Actual behavior

NullPointerException is thrown.

Error message/stack trace

java.lang.NullPointerException: null
              at com.microsoft.sqlserver.jdbc.SQLServerBulkCopy.writeSqlVariant(SQLServerBulkCopy.java:2632)
              at com.microsoft.sqlserver.jdbc.SQLServerBulkCopy.writeColumnToTdsWriter(SQLServerBulkCopy.java:2598)
              at com.microsoft.sqlserver.jdbc.SQLServerBulkCopy.writeColumn(SQLServerBulkCopy.java:3112)
              at com.microsoft.sqlserver.jdbc.SQLServerBulkCopy.writeBatchData(SQLServerBulkCopy.java:3682)
              at com.microsoft.sqlserver.jdbc.SQLServerBulkCopy.doInsertBulk(SQLServerBulkCopy.java:1582)
              at com.microsoft.sqlserver.jdbc.SQLServerBulkCopy$1InsertBulk.doExecute(SQLServerBulkCopy.java:673)
              at com.microsoft.sqlserver.jdbc.TDSCommand.execute(IOBuffer.java:7748)
              at com.microsoft.sqlserver.jdbc.SQLServerConnection.executeCommand(SQLServerConnection.java:4410)
              at com.microsoft.sqlserver.jdbc.SQLServerBulkCopy.sendBulkLoadBCP(SQLServerBulkCopy.java:707)
              at com.microsoft.sqlserver.jdbc.SQLServerBulkCopy.writeToServer(SQLServerBulkCopy.java:1670)
              at com.microsoft.sqlserver.jdbc.SQLServerBulkCopy.writeToServer(SQLServerBulkCopy.java:630)
              at com.microsoft.sqlserver.jdbc.SQLServerPreparedStatement.executeBatch(SQLServerPreparedStatement.java:2361)

Any other details that can be helpful

I guess it should rely on column meta data stored in passed ISQLServerBulkData in this scenario.

JDBC trace logs

N/A

[typhoon2k]

It seems this is duplicate of #2442.