test(quic): exercise the actual driver PTO path, not a simulation

The existing PtoCryptoRetransmitTest simulated the driver inline: it set pendingPing=true and called requeueAllInflightCrypto by hand, then asserted the next drain emitted CRYPTO. That checked the helpers worked but never noticed when the DRIVER stopped calling requeueAllInflightCrypto — which is exactly the regression that bit us in commits c0d7b6031 (qlog merge) and again in cf2303a38 (lock-split refactor). Extract the PTO-fired logic from QuicConnectionDriver.sendLoop into a top-level internal helper handlePtoFired(conn). Driver and test now both call the same function — if anyone unwires the requeue from that helper or rewrites sendLoop to do volatile-only updates, the test breaks. Verified the regression-catch by stripping the requeue from handlePtoFired and re-running the test: it fails with an AssertionError on the PTO retransmit packet check, as expected. Restored the helper, test green again. https://claude.ai/code/session_01HcvfQq1ttPV9PkRoJb4nyT
2026-05-07 02:50:31 +00:00
parent cf2303a38d
commit b579c766a4
2 changed files with 58 additions and 48 deletions
@@ -91,15 +91,16 @@ class PtoCryptoRetransmitTest {
                "no PTO yet, no fresh data → second drain must be empty (got ${emptyDrain?.size} bytes)",
            )

-            // Simulate the driver's PTO branch firing: requeue the
-            // unacknowledged CRYPTO and set the PING flag.
-            client.lock.lock()
-            try {
-                client.requeueAllInflightCrypto(EncryptionLevel.INITIAL)
-                client.pendingPing = true
-            } finally {
-                client.lock.unlock()
-            }
+            // Drive the EXACT helper QuicConnectionDriver.sendLoop
+            // calls when its PTO timer fires. Earlier versions of
+            // this test inlined the simulation (set pendingPing,
+            // call requeueAllInflightCrypto manually) — but that
+            // hid the regression where the driver itself stopped
+            // calling requeueAllInflightCrypto. Calling
+            // [handlePtoFired] keeps the test in lockstep with the
+            // production code path: if anyone unwires the requeue
+            // again, this test breaks.
+            handlePtoFired(client)

            // Next drain must emit a fresh Initial packet carrying
            // the ClientHello CRYPTO at the original offset.