assertThat(Primitives.unwrap(int.class)).isEqualTo(int.class);
    assertThat(Primitives.unwrap(String.class)).isEqualTo(String.class);
  }

  public void testAllPrimitiveTypes() {
    Set<Class<?>> primitives = Primitives.allPrimitiveTypes();
    assertThat(primitives)
        .containsExactly(
            boolean.class,
            byte.class,
            char.class,