/**
     * Compares two model versions.
     *
     * @param first the first version.
     * @param second the second version.
     * @return negative if the first version is newer than the second version, zero if they are the same or positive if
     * the second version is the newer.
     */
    private static int compareModelVersions(String first, String second) {

              (e1, e2) -> {
                // requireNonNull is safe because the first `size` elements have been filled in.
                requireNonNull(e1);
                requireNonNull(e2);
                return comparator.compare(e1.getKey(), e2.getKey());
              });
          // requireNonNull is safe because the first `size` elements have been filled in.
          Entry<K, V> firstEntry = requireNonNull(entryArray[0]);

    assertTrue(result.isEmpty());
    testProp.setProperty("first", "true");

    result = Maps.fromProperties(testProp);
    assertEquals("true", result.get("first"));
    assertEquals(1, result.size());
    testProp.setProperty("second", "null");

    result = Maps.fromProperties(testProp);
    assertEquals("true", result.get("first"));
    assertEquals("null", result.get("second"));

    assertTrue(result.isEmpty());
    testProp.setProperty("first", "true");

    result = Maps.fromProperties(testProp);
    assertEquals("true", result.get("first"));
    assertEquals(1, result.size());
    testProp.setProperty("second", "null");

    result = Maps.fromProperties(testProp);
    assertEquals("true", result.get("first"));
    assertEquals("null", result.get("second"));

              (e1, e2) -> {
                // requireNonNull is safe because the first `size` elements have been filled in.
                requireNonNull(e1);
                requireNonNull(e2);
                return comparator.compare(e1.getKey(), e2.getKey());
              });
          // requireNonNull is safe because the first `size` elements have been filled in.
          Entry<K, V> firstEntry = requireNonNull(entryArray[0]);

  private static final class NoInterface {}

  private abstract static class Implementation<K, V> implements Iterable<V>, Map<K, V> {}

  private abstract static class First<T> {}

  private abstract static class Second<D> extends First<D> {}

  private abstract static class Third<T, D> extends Second<T> {}

  private abstract static class Fourth<T, D> extends Third<D, T> {}

    // Changes before the partition is retrieved are reflected
    list.set(0, 3);
    List<Integer> first = partitions.next();

    // Changes after are not
    list.set(0, 4);

    assertEquals(ImmutableList.of(3), first);
  }

  @J2ktIncompatible // Arrays.asList(...).subList() doesn't implement RandomAccess in J2KT.

   *     message is formed by replacing each {@code %s} placeholder in the template with an
   *     argument. These are matched by position - the first {@code %s} gets {@code
   *     errorMessageArgs[0]}, etc. Unmatched arguments will be appended to the formatted message in
   *     square braces. Unmatched placeholders will be left as-is.

  private static final class NoInterface {}

  private abstract static class Implementation<K, V> implements Iterable<V>, Map<K, V> {}

  private abstract static class First<T> {}

  private abstract static class Second<D> extends First<D> {}

  private abstract static class Third<T, D> extends Second<T> {}

  private abstract static class Fourth<T, D> extends Third<D, T> {}

   * the two sets. If you have reason to believe one of your sets will generally be smaller than the
   * other, pass it first. Unfortunately, since this method sets the generic type of the returned
   * set based on the type of the first set passed, this could in rare cases force you to make a
   * cast, for example:
   *
   * <pre>{@code
   * Set<Object> aFewBadObjects = ...