"Test::Future::Deferred" - a future which completes later

       Paul Evans <leonerd@leonerd.org.uk>

perl v5.40.0                                       2024-10-26                        Test::Future::Deferred(3pm)

       This subclass of Future provides two new methods and an implementation of the "await" interface, which
       allows the futures to appear pending at first, but then to complete when "get" is called at the toplevel
       on one of them.

       This behaviour is useful in unit tests to check that behaviour of a module under test is correct even
       with non-immediate futures, as it allows a future to easily be constructed that will complete "soon", but
       not yet, without needing an event loop.

       Because these futures provide their own "await" method, they shouldn't be mixed in the same program with
       other kinds of futures from real event systems or similar.

done_later
          $f->done_later( @args );

       Equivalent to invoking the regular "done" method as part of the "await" operation called on the toplevel
       future. This makes the future complete with the given result, but only when "get" is called.

   fail_later
          $f->fail_later( $message, $category, @details );

       Equivalent to invoking the regular "fail" method as part of the "await" operation called on the toplevel
       future. This makes the future complete with the given failure, but only when "get" is called. As the
       "failure" method also waits for completion of the future, then it will return the failure message given
       here also.

       "Test::Future::Deferred" - a future which completes later

          my $future = Test::Future::Deferred->done_later( 1, 2, 3 );

          # Future is not ready yet

          my @result = $future->get;