Replace deprecated path.alias_manager and AliasManager when Drupal 8.8 becomes the lowest supported version

OK, yes that's fine. I started to look at it, as those were the two new tests I wrote. I was concerned that I had introduced some deprecated code, but could not discover where I went wrong. It is also odd that the Actions and Conditions tests behave differently, so maybe that is an indication that the problem was further down in Core and not me adding new deprecated code.

After posting, I realised that the deprecations were nothing to do with how I had written then tests, but that these tests are now showing the use of the deprecated code in the four actions that involve aliases:

rules_entity_path_alias_create:entity:node
rules_path_alias_create
rules_path_alias_delete_by_alias
rules_path_alias_delete_by_path

and the two conditions:

rules_path_alias_exists
rules_path_has_alias

I may work on a patch, but not just yet as it is not top priotity. So anyone else is welcome to pick this up if they want to, just assign the issue to yourself when doing so, to avoid us duplicating effort.

I have tested patch #7 locally and on Travis and can confirm that you have sucessfully removed
2x: The \Drupal\Core\Path\AliasManager class is deprecated in drupal:8.8.0

and as expected, we still have the
4x: \Drupal\Core\Path\AliasStorage is deprecated in drupal:8.8.0

If you want to run tests on d.o. and show deprecations you can add this change from #3089502-24: [meta] Rules deprecated code into your patch file. The output is long and not especially readable (it is summarised when I run tests locally and on Travis) but if you know what deprecation message you are looking for it can be searched for easily. It will cause the test to fail though, so need to run again without it to get a green.

We can now start planning on dropping core 8.7 support so un-postponing this. Let's start with an easy one. Patch in #7 still applies, but re-testing just to make sure all is OK.

Thanks for pointing me to that issue. Good plan for final 8.7 release before any more of this deprecation work.

I'll help with anything I can do, but also I will hold of un-postponing these issues, as you have already said you are not working on this module first. It would have been so helpful if DA had given us some separation between 8.7 being unsupported and D9 being released.

Thanks. I will update my Travis repo and check the deprecation count and messages. Will probably have to adjust the allowed count upwards, now that we have lots of new tests :-)