v0.24.1

Added

• It is now possible to compare actors with if a is b
  • This is a stop gap measure.
  • Equality comparison requires the Eq protocol and this awaits the planned
    actor / class unification work

Changed

• Change TCPListenConnection callback on_error(c, error: str) to
  on_listen(c, error: ?str). Previously, the on_error() callback was called
  if there was an error establishing the listening connection. It is now also
  called in the positive case, when we have successfully established the
  listening connection. If the error argument is None, all went well whereas
  if it is set, there was an error.

Fixed

• Dependencies are now idempotently fetched, i.e. if we first look if we already
  have the configured hash locally and use that. We only fetch it if we don't
  have a dependency locally.
  • Previously, acton build would effectively require an Internet connection,
    which is now fixed. Like now, you can do acton fetch in a repo to fetch
    all dependencies locally and from there on you can work in "airplane mode".
• Dependency hash mismatch is now correctly checked and treated as an error.

Testing / CI / Build

• TCP tests have been rewritten to use the new TCPListenConnection on_listen
  callback to properly sequence the test so we first establish the server and
  then start the client. This removes a racy condition which lead to flaky test
  failures.
• Stopped testing on MacOS 12, which is EoL.