ImmutableMultimap.builderWithExpectedKeys(1);
    builder.put("key", "value");
    assertThat(builder.build().entries()).containsExactly(immutableEntry("key", "value"));
  }

  public void testBuilderWithExpectedValuesPerKeyNegative() {
    assertThrows(
        IllegalArgumentException.class, () -> ImmutableMultimap.builder().expectedValuesPerKey(-1));
  }

  public void testBuilderWithExpectedValuesPerKeyZero() {