public void testRemoveUnsupported() {
    assertThrows(UnsupportedOperationException.class, () -> getMultiset().remove(e0(), 2));
  }

  @CollectionFeature.Require(SUPPORTS_REMOVE)
  public void testRemoveZeroNoOp() {
    int originalCount = getMultiset().count(e0());
    assertEquals("old count", originalCount, getMultiset().remove(e0(), 0));
    expectUnchanged();
  }

  @CollectionSize.Require(absent = ZERO)