[CASSANDRA-17695] Fix AbstractCell#toString throws MarshalException for cell in collection

• Type: Bug
• Status: Resolved
• Priority: Normal
• Resolution: Fixed
• Fix Version/s: 4.1-beta1, 4.1
• Component/s: Legacy/Core
• Bug Category: Degradation - Other Exception
• Severity: Low
• Complexity: Low Hanging Fruit
• Discovered By: Unit Test
• Platform: All
• Since Version: 3.0.0

Source Control Link

https://github.com/apache/cassandra/commit/a9725b681b948f2122f3d48b96a5c4e7403d2c39

Test and Documentation Plan

Added test verifying that MarshalException no longer occurs when calling AbstractCell#toString after the fix.

• Assignee: Francisco Guerrero
• Reporter: Yifan Cai

Authors

Francisco Guerrero

Reviewers

Caleb Rackliffe, Yifan Cai

• Created: 16/Jun/22 21:50
• Updated: 16/Dec/22 21:54
• Resolved: 30/Jun/22 01:17

Description

AbstractCell#toString is broken when calling on some cells in multi-cell collections.

With the following types are unmarshallable: [date, duration, smallint, time, tinyint].

The test to discover the unmarshallable types is

@Test
public void testUnmarshallableInMulticellCollection()
{
    List<CQL3Type.Native> unmarshallableTypes = new ArrayList<>();
    for (CQL3Type.Native nativeType : CQL3Type.Native.values())
    {
        ColumnMetadata c = fakeColumn("c", MapType.getInstance(Int32Type.instance, nativeType.getType(), true));
        BufferCell cell = BufferCell.tombstone(c, 0, 4, CellPath.create(ByteBufferUtil.bytes(4)));
        try
        {
            cell.toString();
        }
        catch (MarshalException m)
        {
            unmarshallableTypes.add(nativeType);
        }
    }
    System.out.println("Unmarshallable types: " + unmarshallableTypes);
}

At the first sight, the error is caused by trying to deserialize the values of the tombstone cells. The values are empty, hence the failure.