assertThrows(PotentialDeadlockException.class, () -> readLockA.lock());
    checkMessage(expected, "LockB -> ReadWriteA", "ReadWriteA -> LockB");
  }

  public void testReadLock_transitive() {
    readLockA.lock(); // Establish an ordering from readLockA -> lockB.
    lockB.lock();
    lockB.unlock();
    readLockA.unlock();

    // Establish an ordering from lockB -> readLockC.