Scenario:

• process instance with a variable of type object
• update that object value implicity (i.e. without calling DelegateExecution#setVariable or similar)
• process instance ends in same transaction

Result:

• variable update is not reflected in history

Expected behavior:

• it should be visible in history

Variants:

• this is not only the case for the process scope, but basically for any scope (i.e. updates local variables of subprocesses are not reflected in history if the subprocess ends in same transaction)

Root cause:

• destroying a scope clears all the variables
• clearing variables drops the cached value
• check for implicit value updates happens only after that and is based on the cached value

Forum post:

• https://forum.camunda.org/t/possible-process-variable-history-subprocess-scope-bug/3309