new EqualsTester()
        .addEqualityGroup(Suppliers.ofInstance("foo"), Suppliers.ofInstance("foo"))
        .addEqualityGroup(Suppliers.ofInstance("bar"))
        .testEquals();
  }

  public void testCompose_equals() {
    new EqualsTester()
        .addEqualityGroup(
            Suppliers.compose(Functions.constant(1), Suppliers.ofInstance("foo")),

  }

  @SuppressWarnings("ReturnValueIgnored")
  public void testMaximumWeight_withoutWeigher() {
    CacheBuilder<Object, Object> builder = CacheBuilder.from(parse("maximumWeight=9000"));
    assertThrows(
        IllegalStateException.class,
        () -> builder.build(CacheLoader.from(Suppliers.ofInstance(null))));
  }

  }

  @SuppressWarnings("ReturnValueIgnored")
  public void testMaximumWeight_withoutWeigher() {
    CacheBuilder<Object, Object> builder = CacheBuilder.from(parse("maximumWeight=9000"));
    assertThrows(
        IllegalStateException.class,
        () -> builder.build(CacheLoader.from(Suppliers.ofInstance(null))));
  }

   * supplier that is serializable, use {@code (Supplier<T> & Serializable) () -> instance}.
   */
  public static <T extends @Nullable Object> Supplier<T> ofInstance(
      @ParametricNullness T instance) {
    return new SupplierOfInstance<>(instance);
  }

  private static final class SupplierOfInstance<T extends @Nullable Object>
      implements Supplier<T>, Serializable {

   * supplier that is serializable, use {@code (Supplier<T> & Serializable) () -> instance}.
   */
  public static <T extends @Nullable Object> Supplier<T> ofInstance(
      @ParametricNullness T instance) {
    return new SupplierOfInstance<>(instance);
  }

  private static final class SupplierOfInstance<T extends @Nullable Object>
      implements Supplier<T>, Serializable {

    new EqualsTester()
        .addEqualityGroup(function, Functions.forSupplier(supplier))
        .addEqualityGroup(Functions.forSupplier(new CountingSupplier()))
        .addEqualityGroup(Functions.forSupplier(Suppliers.ofInstance(12)))
        .addEqualityGroup(Functions.toStringFunction())
        .testEquals();
  }

  @J2ktIncompatible
  @GwtIncompatible // SerializableTester
  public void testForSupplierSerializable() {

    new EqualsTester()
        .addEqualityGroup(function, Functions.forSupplier(supplier))
        .addEqualityGroup(Functions.forSupplier(new CountingSupplier()))
        .addEqualityGroup(Functions.forSupplier(Suppliers.ofInstance(12)))
        .addEqualityGroup(Functions.toStringFunction())
        .testEquals();
  }

  @J2ktIncompatible
  @GwtIncompatible // SerializableTester
  public void testForSupplierSerializable() {

  }

  public void testThreadRenaming() {
    Executor renamingExecutor =
        renamingDecorator(newDirectExecutorService(), Suppliers.ofInstance("FooBar"));
    String oldName = Thread.currentThread().getName();
    renamingExecutor.execute(
        new Runnable() {
          @Override
          public void run() {