Only prohibit 'YEAR' in default mappings. Fixes #1605

Author: bgrainger

src/MySqlConnector/MySqlBulkCopy.cs

@@ -238,11 +238,6 @@ private async ValueTask<MySqlBulkCopyResult> WriteToServerAsync(IOBehavior ioBeh
 				{
 					AddColumnMapping(m_logger, columnMappings, addDefaultMappings, i, destinationColumn, $"@`\uE002\bcol{i}`", $"%COL% = CAST(%VAR% AS UNSIGNED)");
 				}
-				else if (schema[i].DataTypeName == "YEAR")
-				{
-					// the current code can't distinguish between 0 = 0000 and 0 = 2000
-					throw new NotSupportedException("'YEAR' columns are not supported by MySqlBulkLoader.");
-				}
 				else
 				{
 					var type = schema[i].DataType;
@@ -252,6 +247,12 @@ private async ValueTask<MySqlBulkCopyResult> WriteToServerAsync(IOBehavior ioBeh
 					}
 					else if (addDefaultMappings)
 					{
+						if (schema[i].DataTypeName == "YEAR")
+						{
+							// the current code can't distinguish between 0 = 0000 and 0 = 2000
+							throw new NotSupportedException("'YEAR' columns are not supported by MySqlBulkCopy.");
+						}
+
 						Log.AddingDefaultColumnMapping(m_logger, i, destinationColumn);
 						columnMappings.Add(new(i, destinationColumn));
 					}

tests/IntegrationTests/BulkLoaderSync.cs

@@ -1145,6 +1145,67 @@ public void BulkCopyColumnMappingsInvalidDestinationColumn()
 		Assert.Throws<InvalidOperationException>(() => bulkCopy.WriteToServer(dataTable));
 	}
 
+	[Fact]
+	public void BulkCopyToTableWithYear()
+	{
+		using var connection = new MySqlConnection(GetLocalConnectionString());
+		connection.Open();
+
+		using var cmd = connection.CreateCommand();
+		cmd.CommandText = """
+			DROP TABLE IF EXISTS bulk_copy_year;
+			CREATE TABLE bulk_copy_year(int_value int NULL, year_value year NULL)
+			""";
+		cmd.ExecuteNonQuery();
+
+		var bulkCopy = new MySqlBulkCopy(connection)
+		{
+			DestinationTableName = "bulk_copy_year",
+			ColumnMappings =
+			{
+				new MySqlBulkCopyColumnMapping(0, "int_value", null),
+			},
+		};
+
+		var dt = new DataTable();
+		dt.Columns.Add("numbers");
+		dt.Rows.Add(1);
+		dt.Rows.Add(2);
+
+		bulkCopy.WriteToServer(dt);
+
+		cmd.CommandText = "SELECT COUNT(*) FROM bulk_copy_year WHERE int_value IN (1, 2) AND year_value IS NULL";
+		Assert.Equal(2, Convert.ToInt32(cmd.ExecuteScalar()));
+	}
+
+	[Fact]
+	public void BulkCopyToTableWithYearNotSupported()
+	{
+		using var connection = new MySqlConnection(GetLocalConnectionString());
+		connection.Open();
+
+		using var cmd = connection.CreateCommand();
+		cmd.CommandText = """
+			DROP TABLE IF EXISTS bulk_copy_year;
+			CREATE TABLE bulk_copy_year(int_value int NULL, year_value year NULL)
+			""";
+		cmd.ExecuteNonQuery();
+
+		var bulkCopy = new MySqlBulkCopy(connection)
+		{
+			DestinationTableName = "bulk_copy_year",
+		};
+
+		var dt = new DataTable();
+		dt.Columns.Add("numbers");
+		dt.Columns.Add("year");
+		dt.Rows.Add(1, 2000);
+		dt.Rows.Add(2, 2001);
+
+		var exception = Assert.Throws<NotSupportedException>(() => bulkCopy.WriteToServer(dt));
+		Assert.Equal("'YEAR' columns are not supported by MySqlBulkCopy.", exception.Message);
+	}
+
 	[Fact]
 	public void BulkCopyDoesNotInsertAllRows()
 	{