double fpp = bf.expectedFpp();
    assertThat(fpp).isEqualTo(0.0);
    // usually completed in less than 200 iterations
    while (fpp != 1.0) {
      boolean changed = bf.put(new Object());
      double newFpp = bf.expectedFpp();
      // if changed, the new fpp is strictly higher, otherwise it is the same
      assertTrue(changed ? newFpp > fpp : newFpp == fpp);
      fpp = newFpp;
    }
  }