assertThat(map.putIfAbsent(three, one)).isNull();
    assertThat(map.get(three)).isSameInstanceAs(one);
    assertThat(map.replace(one, three)).isSameInstanceAs(two);
    assertThat(map.get(one)).isSameInstanceAs(three);
    assertThat(map.replace(one, two, three)).isFalse();
    assertThat(map.get(one)).isSameInstanceAs(three);
    assertThat(map.replace(one, three, two)).isTrue();
    assertThat(map.get(one)).isSameInstanceAs(two);

  /*
   * Since Quantiles provides a fluent-style API, each test covers a chain of methods resulting in
   * the computation of one or more quantiles (or in an error) rather than individual methods. The
   * tests are divided into three sections:
   * 1. Tests on a hardcoded dataset for chains starting with median(), quartiles(), and scale(10);
   * 2. Tests on hardcoded datasets include non-finite values for chains starting with scale(10);

  /*
   * Since Quantiles provides a fluent-style API, each test covers a chain of methods resulting in
   * the computation of one or more quantiles (or in an error) rather than individual methods. The
   * tests are divided into three sections:
   * 1. Tests on a hardcoded dataset for chains starting with median(), quartiles(), and scale(10);
   * 2. Tests on hardcoded datasets include non-finite values for chains starting with scale(10);

    Object two = new Object();
    Object three = new Object();
    Object four = new Object();
    Object five = new Object();
    Object six = new Object();

    map.put(one, two);
    map.remove(one);
    assertNotified(listener, one, two, RemovalCause.EXPLICIT);

    map.put(two, three);
    map.remove(two, three);
    assertNotified(listener, two, three, RemovalCause.EXPLICIT);

    map.put(three, four);

    Object two = new Object();
    Object three = new Object();
    Object four = new Object();
    Object five = new Object();
    Object six = new Object();

    map.put(one, two);
    map.remove(one);
    assertNotified(listener, one, two, RemovalCause.EXPLICIT);

    map.put(two, three);
    map.remove(two, three);
    assertNotified(listener, two, three, RemovalCause.EXPLICIT);

    assertEquals("three", map.higherKey("one"));
    assertEquals("three", map.higherKey("r"));
    assertEquals("three", map.ceilingKey("r"));
    assertEquals("one", map.ceilingKey("one"));
    assertEquals(mapEntry("three", 5), map.higherEntry("one"));
    assertEquals(mapEntry("one", 3), map.ceilingEntry("one"));
    assertEquals("one", map.lowerKey("three"));

    }

    /**
     * Creates a new CurlRequest with the HTTP TRACE method for the specified URL.
     *
     * @param url the URL to send the TRACE request to
     * @return a new CurlRequest object configured with the TRACE method and the specified URL
     */
    public static CurlRequest trace(final String url) {
        return new CurlRequest(Method.TRACE, url);
    }

    /**

    assertEquals("three", map.higherKey("one"));
    assertEquals("three", map.higherKey("r"));
    assertEquals("three", map.ceilingKey("r"));
    assertEquals("one", map.ceilingKey("one"));
    assertEquals(mapEntry("three", 5), map.higherEntry("one"));
    assertEquals(mapEntry("one", 3), map.ceilingEntry("one"));
    assertEquals("one", map.lowerKey("three"));

    Map<String, @Nullable Integer> map = new HashMap<>();
    map.put("One", 1);
    map.put("Three", 3);
    map.put("Null", null);
    Function<String, @Nullable Integer> function = Functions.forMap(map);

    assertEquals(1, function.apply("One").intValue());
    assertEquals(3, function.apply("Three").intValue());
    assertThat(function.apply("Null")).isNull();

        ImmutableMap.of("one", 1, "two", 2, "three", 3), "one", 1, "two", 2, "three", 3);
    assertMapEquals(
        ImmutableMap.of("one", 1, "two", 2, "three", 3, "four", 4),
        "one",
        1,
        "two",
        2,
        "three",
        3,
        "four",
        4);
    assertMapEquals(
        ImmutableMap.of("one", 1, "two", 2, "three", 3, "four", 4, "five", 5),
        "one",