[#358] TransactionAbandonedTest: read and write in the abandoned transaction

[vharseko]

Problem

TransactionAbandonedTest.runAndCleanup(name, doRead, doWrite) ignored its flags and always started new TxnAbandoner(_persistit, false, false). So readOnly and readAndWrite ran the noReadsOrWrites scenario, and their assertions held whatever Persistit.cleanup() did with the abandoned transaction.

With the flags passed through, readAndWrite fails with Raw traversed after abandoned expected:<10> but was:<20>. A rolled back transaction is pruned by JournalManager.pruneObsoleteTransactions(), which replays it with ProactiveRollbackListener, not through the CleanupManager queue that the test ran. CleanupManager.poll() calls that method at most once every two seconds, and the test reaches the raw scan well before that.

Change

• runAndCleanup() passes doRead and doWrite to TxnAbandoner.
• After joining the thread and before cleanup(), while the abandoned transaction is still open, runAndCleanup() checks the raw key count: 2 * KEY_RANGE when the transaction wrote, KEY_RANGE otherwise. Nothing can prune the versions of a transaction that has not ended, so the check does not depend on when the product prunes, and it fails if the flags stop reaching the abandoned transaction.
• readAndWrite prunes with pruneObsoleteTransactions(true) before the raw scan. The CleanupManager loop is removed: its queue is empty at that point (Buffer.enqueuePruningAction has no caller), so the loop never ran.

Testing (JDK 11, macOS)

• TransactionAbandonedTest: all 3 tests pass, 15 consecutive runs green.
• With the flags ignored again (false, false): Raw traversed before cleanup expected:<20> but was:<10>.
• Without the pruneObsoleteTransactions(true) call: Raw traversed after abandoned expected:<10> but was:<20>.

Fixes #358

[maximthomas]

praise: The flags now reach the abandoned transaction, and the assertions finally depend on what cleanup() does.

• runAndCleanup() passes doRead/doWrite to TxnAbandoner (TransactionAbandonedTest.java:110); with that, deleting _persistit.cleanup() turns readAndWrite red (Raw traversed after abandoned expected:<10> but was:<20>).
• The raw count before cleanup() (:112-113) is taken while the transaction is still open, so it cannot depend on prune timing.
• pruneObsoleteTransactions(true) (:136) replaces a CleanupManager loop that never ran, and the class stayed green 50/50 on JDK 11 and on all 9 CI rows.