TEST(WiredTigerUtilTest, DupeKeyInTxnRollsBack) {
    WiredTigerUtilHarnessHelper harnessHelper("statistics=(all)");
    auto conn = harnessHelper.getConnection()->getConnection();

    WT_SESSION* session1;
    invariantWTOK(conn->open_session(conn, nullptr, nullptr, &session1));

    auto uri = "table:mytable";
    invariantWTOK(session1->create(session1, uri, "key_format=i,value_format=i"));

    // Open a transaction on session1 and insert key=1, and leave transaction open.
    invariantWTOK(session1->begin_transaction(session1, "isolation=snapshot"));
    {
        WT_CURSOR* cursor;
        invariantWTOK(session1->open_cursor(session1, uri, nullptr, "overwrite=false", &cursor));
        ON_BLOCK_EXIT([&] { cursor->close(cursor); });
        cursor->set_key(cursor, 1);
        cursor->set_value(cursor, 1);
        invariantWTOK(cursor->insert(cursor));
    }

    WT_SESSION* session2;
    invariantWTOK(conn->open_session(conn, nullptr, nullptr, &session2));

    // Open a transaction on session2 and try to insert key=1.
    {
        invariantWTOK(session2->begin_transaction(session2, "isolation=snapshot"));
        WT_CURSOR* cursor;
        invariantWTOK(session2->open_cursor(session1, uri, nullptr, "overwrite=false", &cursor));
        ON_BLOCK_EXIT([&] { cursor->close(cursor); });
        cursor->set_key(cursor, 1);
        cursor->set_value(cursor, 1);
        auto ret = cursor->insert(cursor);
        // Should not return dupe key for something not inserted as of my snapshot.
        ASSERT_NE(ret, WT_DUPLICATE_KEY); // <--- fails
        ASSERT_EQ(ret, WT_ROLLBACK);
    }

    // Let transactions auto-abort when their sessions are closed.
}