AsyncFunction<? super X, ? extends V> fallback) {
      super(input, exceptionType, fallback);
    }

    @Override
    ListenableFuture<? extends V> doFallback(
        AsyncFunction<? super X, ? extends V> fallback, X cause) throws Exception {
      ListenableFuture<? extends V> output = fallback.apply(cause);
      checkNotNull(
          output,

import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutionException;
import org.jspecify.annotations.NullUnmarked;

/**
 * Unit tests for {@link Futures#transformAsync(ListenableFuture, AsyncFunction, Executor)}.
 *
 * @author Nishant Thakkar
 */
@NullUnmarked
@GwtIncompatible
@J2ktIncompatible
public class FuturesTransformAsyncTest extends AbstractChainedListenableFutureTest<String> {

import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutionException;
import org.jspecify.annotations.NullUnmarked;

/**
 * Unit tests for {@link Futures#transformAsync(ListenableFuture, AsyncFunction, Executor)}.
 *
 * @author Nishant Thakkar
 */
@NullUnmarked
@GwtIncompatible
@J2ktIncompatible
public class FuturesTransformAsyncTest extends AbstractChainedListenableFutureTest<String> {

      Class<X> exceptionType, AsyncClosingFunction<? super X, W> fallback, Executor executor) {
    checkNotNull(fallback);
    AsyncFunction<X, W> asyncFunction =
        new AsyncFunction<X, W>() {
          @Override
          public ListenableFuture<W> apply(X exception) throws Exception {
            return state.closeables.applyAsyncClosingFunction(fallback, exception);

  /**
   * Returns a {@code Future} whose result is taken from this {@code Future} or, if this {@code
   * Future} fails with the given {@code exceptionType}, from the result provided by the {@code
   * fallback}. {@link AsyncFunction#apply} is not invoked until the primary input has failed, so if
   * the primary input succeeds, it is never invoked. If, during the invocation of {@code fallback},

   * Returns a {@code Future} whose result is taken from the given primary {@code input} or, if the
   * primary input fails with the given {@code exceptionType}, from the result provided by the
   * {@code fallback}. {@link AsyncFunction#apply} is not invoked until the primary input has
   * failed, so if the primary input succeeds, it is never invoked. If, during the invocation of