@CollectionSize.Require(absent = ZERO)
  public void testRemove_present() {
    int initialSize = getMap().size();
    assertEquals("remove(present) should return the associated value", v0(), getMap().remove(k0()));
    assertEquals(
        "remove(present) should decrease a map's size by one.", initialSize - 1, getMap().size());
    expectMissing(e0());
  }

        try {
            Artifact artifact = new Artifact("fess-theme-test", "1.0.0");
            themeHelper.getJarFile(artifact);
            fail("Should throw ThemeException");
        } catch (Exception e) {
            // Should throw ThemeException or other exception related to file not found
            assertTrue(e.getMessage().contains("does not exist") || e instanceof ThemeException);
        }
    }

  public void testGet_yes() {
    assertEquals("get(present) should return the associated value", v0(), get(k0()));
  }

  public void testGet_no() {
    assertNull("get(notPresent) should return null", get(k3()));
  }

  @MapFeature.Require(ALLOWS_NULL_KEY_QUERIES)
  public void testGet_nullNotContainedButAllowed() {
    assertNull("get(null) should return null", get(null));
  }

        getMethodName() + "(firstElement) should return 0", 0, find(getOrderedElements().get(0)));
  }

  public void testFind_no() {
    assertEquals(getMethodName() + "(notPresent) should return -1", -1, find(e3()));
  }

  @CollectionFeature.Require(ALLOWS_NULL_VALUES)
  public void testFind_nullNotContainedButSupported() {
    assertEquals(getMethodName() + "(nullNotPresent) should return -1", -1, find(null));
  }

  public void testAbsent() {
    assertEquals(
        "Map.merge(absent, value, function) should return value",
        v3(),
        getMap()
            .merge(
                k3(),
                v3(),
                (oldV, newV) -> {
                  throw new AssertionFailedError(
                      "Should not call merge function if key was absent");
                }));
    expectAdded(e3());
  }

        assertNotNull("Mapping option should not be null", mappingOption);
        OptionalThing<JsonFieldNaming> fieldNamingOpt = mappingOption.getFieldNaming();
        assertTrue("Field naming should be present", fieldNamingOpt.isPresent());
        assertEquals("Field naming should be CAMEL_TO_LOWER_SNAKE", JsonFieldNaming.CAMEL_TO_LOWER_SNAKE, fieldNamingOpt.get());
    }

    public void test_instanceCreation() {

  public void testRetainAll_duplicatesKept() {
    E[] array = createSamplesArray();
    array[1] = e0();
    collection = getSubjectGenerator().create(array);
    assertFalse(
        "containsDuplicates.retainAll(superset) should return false",
        collection.retainAll(MinimalCollection.of(createSamplesArray())));
    expectContents(array);
  }

  @CollectionFeature.Require(SUPPORTS_REMOVE)
  @CollectionSize.Require(SEVERAL)

    assertFalse(
        "Two Sets should not be equal if exactly one of them contains null.",
        getSet().equals(other));
  }

  @CollectionSize.Require(absent = CollectionSize.ZERO)
  public void testEquals_smallerSet() {
    Collection<E> fewerElements = getSampleElements(getNumElements() - 1);
    assertFalse(
        "Sets of different sizes should not be equal.",

    assertFalse(
        "Two Sets should not be equal if exactly one of them contains null.",
        getSet().equals(other));
  }

  @CollectionSize.Require(absent = CollectionSize.ZERO)
  public void testEquals_smallerSet() {
    Collection<E> fewerElements = getSampleElements(getNumElements() - 1);
    assertFalse(
        "Sets of different sizes should not be equal.",

    assertFalse(
        "A List should not equal another List containing different elements.",
        getList().equals(other));
  }

  @CollectionSize.Require(absent = CollectionSize.ZERO)
  public void testEquals_otherListContainingNull() {
    List<E> other = new ArrayList<>(getSampleElements());
    other.set(other.size() / 2, null);
    assertFalse(