ListenableFuture<String> f = FluentFuture.from(SettableFuture.create());
    assertThat(FluentFuture.from(f)).isSameInstanceAs(f);
  }

  public void testFromNonFluentFuture() throws Exception {
    ListenableFuture<String> f =
        new SimpleForwardingListenableFuture<String>(immediateFuture("a")) {};
    verify(!(f instanceof FluentFuture));
    assertThat(FluentFuture.from(f).get()).isEqualTo("a");

    ClosingFuture<Closeable> closingFuture =
        ClosingFuture.submit(closer -> closer.eventuallyClose(mockCloseable, executor), executor);
    FluentFuture<Closeable> unused = closingFuture.finishToFuture();
    assertThrows(
        IllegalStateException.class,
        () -> {
          FluentFuture<Closeable> unused2 = closingFuture.finishToFuture();
        });
  }

    ListenableFuture<String> f = FluentFuture.from(SettableFuture.create());
    assertThat(FluentFuture.from(f)).isSameInstanceAs(f);
  }

  public void testFromNonFluentFuture() throws Exception {
    ListenableFuture<String> f =
        new SimpleForwardingListenableFuture<String>(immediateFuture("a")) {};
    verify(!(f instanceof FluentFuture));
    assertThat(FluentFuture.from(f).get()).isEqualTo("a");

    ClosingFuture<Closeable> closingFuture =
        ClosingFuture.submit(closer -> closer.eventuallyClose(mockCloseable, executor), executor);
    FluentFuture<Closeable> unused = closingFuture.finishToFuture();
    assertThrows(
        IllegalStateException.class,
        () -> {
          FluentFuture<Closeable> unused2 = closingFuture.finishToFuture();
        });
  }

import java.util.concurrent.Executor;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import org.jspecify.annotations.Nullable;

/**
 * {@link FluentFuture} that forwards all calls to a delegate.
 *
 * <p><b>Warning:</b> The methods of {@code ForwardingFluentFuture} forward <b>indiscriminately</b>

    ClosingFuture<Closeable> closingFuture =
        ClosingFuture.submit(closer -> closer.eventuallyClose(mockCloseable, executor), executor);
    FluentFuture<Closeable> unused = closingFuture.finishToFuture();
    assertThrows(
        IllegalStateException.class,
        () ->
            closingFuture.finishToValueAndCloser(

          ? Futures.whenAllSucceed(inputFutures())
          : Futures.whenAllComplete(inputFutures());
    }

    private ImmutableList<FluentFuture<?>> inputFutures() {
      return FluentIterable.from(inputs)
          .<FluentFuture<?>>transform(future -> future.state.future)
          .toList();
    }
  }

  /**

    ClosingFuture<Closeable> closingFuture =
        ClosingFuture.submit(closer -> closer.eventuallyClose(mockCloseable, executor), executor);
    FluentFuture<Closeable> unused = closingFuture.finishToFuture();
    assertThrows(
        IllegalStateException.class,
        () ->
            closingFuture.finishToValueAndCloser(

     * should throw IllegalStateException only when they use static state.
     *
     * Why do we deviate here? The answer: We want for fluentFuture.getDone() to throw the same
     * exception as Futures.getDone(fluentFuture).
     */
    checkState(future.isDone(), "Future was expected to be done: %s", future);
    return getUninterruptibly(future);
  }

  /**