Allow psysh version 0.8.x.

[greg-1-anderson]

Drupal Console allows "psy/psysh": "0.6.* || ~0.8", which can cause Composer angst if Drupal Console is added to a project before Drush.

There appear to be no API changes in 0.8, at least not that affect Drush.

[greg-1-anderson]

~0.6 already includes ~0.8. This PR may improve some edge cases. The Drush 8.x version (#2853) has a couple of minor build fixes; these should be merged separately if the psysh version constraint is not desired.

[damiankloip]

I'm not overly sure we need the two constraints here? I think Drupal console added the 0.6.* constraint for drush originally maybe - I'm not 100% sure because I use drupal console...never. I don't think we should do the same oddities they do? Drupal console literally does nothing with their psysh setup (just the min required to have a working psysh shell), so any version should be ok for them to be honest. i.e. the latest

[damiankloip]

Seems like a good idea to just sync with the Console folks and lock it down from there? I thought Drupal console was not trying to do the same things as Drush... 🤦‍♂️

[damiankloip]

From https://www.drupal.org/node/2391219

There might be some overlap, but the console maintainers were smart enough to keep the console niche and concentrate on scaffolding, which is not something that drush core does

sure 🤔

[thom8]

Could a metapackage help here which can have tighter constraints and even sit behind latest versions to ensure compatibility.

for example -- https://packagist.org/packages/thom8/drupalcli

[greg-1-anderson]

Per @damiankloip, keeping ~0.6 as our constraint. This includes the latest release (until 1.0.0).