Future.all depends on futures implementing FutureInternal

[doctorpangloss]

Version

4.5.11

Context

class com.hiddenswitch.framework.tests.impl.FrameworkTestBase$Checkpoint cannot be cast to class io.vertx.core.impl.future.FutureInternal (com.hiddenswitch.framework.tests.impl.FrameworkTestBase$Checkpoint and io.vertx.core.impl.future.FutureInternal are in unnamed module of loader 'app')
java.lang.ClassCastException: class com.hiddenswitch.framework.tests.impl.FrameworkTestBase$Checkpoint cannot be cast to class io.vertx.core.impl.future.FutureInternal (com.hiddenswitch.framework.tests.impl.FrameworkTestBase$Checkpoint and io.vertx.core.impl.future.FutureInternal are in unnamed module of loader 'app')
	at io.vertx.core.impl.future.CompositeFutureImpl.init(CompositeFutureImpl.java:67)
	at io.vertx.core.impl.future.CompositeFutureImpl.create(CompositeFutureImpl.java:45)
	at io.vertx.core.impl.future.CompositeFutureImpl.all(CompositeFutureImpl.java:29)
	at io.vertx.core.CompositeFuture.all(CompositeFuture.java:88)

A Checkpoint implements Future<Void> which should be allowed. But this breaks in 4.5 when an instance of Checkpoint is passed to Future.all.

Do you have a reproducer?

Future.all(new Future<Void> { ... });

This will fail for any valid user-authored implementation of future.

This works on 4.4.

• Link to github project/gist

Steps to reproduce

1. Implement Future in a user code class.
2. Observe that Future.all will raise an exception trying to cast Future to FutureInternal. This is unexpected
3. Implementing FutureInternal resolves the issue.

[tsegismont]

Fixed by 0b41047