[dbsp] Fix flaky exchange wire-protocol tests under random fault injection - #6808
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…ction new_message_sent_without_waiting_after_a_ping and pings_repeatedly_without_retransmitting drive the wire protocol directly against a single hand-accepted TcpStream, so they can't tolerate the random inject_fault() connection drops meant for the round-based resilience tests: a dropped connection makes the client reconnect to a fresh socket the test never accepts, leaving it reading a dead stream and panicking on an unexpected None. This fixes the problem by disabling fault injection while the tests that can tolerate it run. These tests run quickly, so other tests can still benefit from fault injection. Signed-off-by: Ben Pfaff <blp@feldera.com>
mihaibudiu
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Aug 5, 2026
mythical-fred
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Aug 5, 2026
mythical-fred
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Correct fix: the two protocol-level tests drive a hand-accepted TcpStream and have no way to recover from a inject_fault() disconnect. A refcounted FAULT_INJECTION_DISABLE_COUNT toggled by an RAII FaultInjectionDisabled guard is exactly the right shape — nests safely, unwinds cleanly on panic, and leaves the round-based resilience tests unchanged.
The scoping is tight (two tests, both fast, both explicitly commented as protocol-level) so fault injection still covers the tests it was designed for.
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new_message_sent_without_waiting_after_a_ping and
pings_repeatedly_without_retransmitting drive the wire protocol directly against a single hand-accepted TcpStream, so they can't tolerate the random inject_fault() connection drops meant for the round-based resilience tests: a dropped connection makes the client reconnect to a fresh socket the test never accepts, leaving it reading a dead stream and panicking on an unexpected None.
This fixes the problem by disabling fault injection while the tests that can tolerate it run. These tests run quickly, so other tests can still benefit from fault injection.
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