Method BuildTimeBackwardsTest

src/test/txrequest_tests.cpp:579–622

Add to scenario a test that exercises clocks that go backwards. */

/** Add to scenario a test that exercises clocks that go backwards. */
void TxRequestTest::BuildTimeBackwardsTest(Scenario& scenario)
{
    auto peer1 = scenario.NewPeer();
    auto peer2 = scenario.NewPeer();
    auto gtxid = scenario.NewGTxid({{peer1, peer2}});

    // Announce from peer2.
    auto reqtime = scenario.Now() + RandomTime8s();
    scenario.ReceivedInv(peer2, gtxid, true, reqtime);
    scenario.Check(peer2, {}, 1, 0, 0, "r1");
    scenario.AdvanceTime(reqtime - scenario.Now());
    scenario.Check(peer2, {gtxid}, 1, 0, 0, "r2");
    // Check that if the clock goes backwards by 1us, the transaction would stop being requested.
    scenario.Check(peer2, {}, 1, 0, 0, "r3", -MICROSECOND);
    // But it reverts to being requested if time goes forward again.
    scenario.Check(peer2, {gtxid}, 1, 0, 0, "r4");

    // Announce from peer1.
    if (m_rng.randbool()) scenario.AdvanceTime(RandomTime8s());
    scenario.ReceivedInv(peer1, gtxid, true, MAX_TIME);
    scenario.Check(peer2, {gtxid}, 1, 0, 0, "r5");
    scenario.Check(peer1, {}, 1, 0, 0, "r6");

    // Request from peer1.
    if (m_rng.randbool()) scenario.AdvanceTime(RandomTime8s());
    auto expiry = scenario.Now() + RandomTime8s();
    scenario.RequestedTx(peer1, gtxid.ToUint256(), expiry);
    scenario.Check(peer1, {}, 0, 1, 0, "r7");
    scenario.Check(peer2, {}, 1, 0, 0, "r8");

    // Expiration passes.
    scenario.AdvanceTime(expiry - scenario.Now());
    scenario.Check(peer1, {}, 0, 0, 1, "r9");
    scenario.Check(peer2, {gtxid}, 1, 0, 0, "r10"); // Request goes back to peer2.
    scenario.CheckExpired(peer1, gtxid);
    scenario.Check(peer1, {}, 0, 0, 1, "r11", -MICROSECOND); // Going back does not unexpire.
    scenario.Check(peer2, {gtxid}, 1, 0, 0, "r12", -MICROSECOND);

    // Peer2 goes offline, meaning no viable announcements remain.
    if (m_rng.randbool()) scenario.AdvanceTime(RandomTime8s());
    scenario.DisconnectedPeer(peer2);
    scenario.Check(peer1, {}, 0, 0, 0, "r13");
    scenario.Check(peer2, {}, 0, 0, 0, "r14");
}

/** Add to scenario a test that involves RequestedTx() calls for txhashes not returned by GetRequestable. */
void TxRequestTest::BuildWeirdRequestsTest(Scenario& scenario)