assertEquals(0, numCalls.get());
    reject.set(false);
    executor.execute(task);
    assertEquals(1, numCalls.get());
  }

  /*
   * Under Android, MyError propagates up and fails the test?
   *
   * TODO(b/218700094): Does this matter to prod users, or is it just a feature of our testing
   * environment? If the latter, maybe write a custom Executor that avoids failing the test when it

    assertEquals(0, numCalls.get());
    reject.set(false);
    executor.execute(task);
    assertEquals(1, numCalls.get());
  }

  /*
   * Under Android, MyError propagates up and fails the test?
   *
   * TODO(b/218700094): Does this matter to prod users, or is it just a feature of our testing
   * environment? If the latter, maybe write a custom Executor that avoids failing the test when it

   *       MoreExecutors#newSequentialExecutor} wrapper around {@code directExecutor()}. More
   *       complex cases may require using thread pools or making deeper changes.)
   *   <li>If an exception propagates out of a {@code Runnable}, it is not necessarily seen by any
   *       {@code UncaughtExceptionHandler} for the thread. For example, if the callback passed to

   * the output future list. (Such races are impossible to solve without global synchronization of
   * all future completions. And they should have little practical impact.)
   *
   * <p>Cancelling a delegate future propagates to input futures once all the delegates complete,
   * either from cancellation or because an input future has completed. If N futures are passed in,

   * the output future list. (Such races are impossible to solve without global synchronization of
   * all future completions. And they should have little practical impact.)
   *
   * <p>Cancelling a delegate future propagates to input futures once all the delegates complete,
   * either from cancellation or because an input future has completed. If N futures are passed in,

/**
 * Tester to ensure forwarding wrapper works by delegating calls to the corresponding method with
 * the same parameters forwarded and return value forwarded back or exception propagated as is.
 *
 * <p>For example:
 *
 * <pre>{@code
 * new ForwardingWrapperTester().testForwarding(Foo.class, new Function<Foo, Foo>() {
 *   public Foo apply(Foo foo) {
 *     return new ForwardingFoo(foo);
 *   }

/**
 * Tester to ensure forwarding wrapper works by delegating calls to the corresponding method with
 * the same parameters forwarded and return value forwarded back or exception propagated as is.
 *
 * <p>For example:
 *
 * <pre>{@code
 * new ForwardingWrapperTester().testForwarding(Foo.class, new Function<Foo, Foo>() {
 *   public Foo apply(Foo foo) {
 *     return new ForwardingFoo(foo);
 *   }

  }

  @J2ktIncompatible
  @GwtIncompatible // propagate
  public void testPropagate_noneDeclared_unchecked() {
    assertThrows(SomeUncheckedException.class, () -> propagate(new SomeUncheckedException()));
  }

  @J2ktIncompatible
  @GwtIncompatible // propagate
  public void testPropagate_noneDeclared_error() {
    assertThrows(SomeError.class, () -> propagate(new SomeError()));
  }

  @J2ktIncompatible

  }

  @J2ktIncompatible
  @GwtIncompatible // propagate
  public void testPropagate_noneDeclared_unchecked() {
    assertThrows(SomeUncheckedException.class, () -> propagate(new SomeUncheckedException()));
  }

  @J2ktIncompatible
  @GwtIncompatible // propagate
  public void testPropagate_noneDeclared_error() {
    assertThrows(SomeError.class, () -> propagate(new SomeError()));
  }

  @J2ktIncompatible

      // Bug in inputFuture.get(). Propagate to the output Future so that its consumers don't hang.
      setException(e);
      return;
    } catch (Error e) {
      /*
       * StackOverflowError, OutOfMemoryError (e.g., from allocating ExecutionException), or
       * something. Try to treat it like a RuntimeException. If we overflow the stack again, the
       * resulting Error will propagate upward up to the root call to set().