Comment 11 for bug 1492252

Hi Brian, I started working on the implementation in unity-scopes-shell at the time we discussed this, but it turned out to be more complex than expected.

First off, the solution with preview_by_key I suggested above turned out to be a no-go, because it was incompatible with how preview actions work (I should have noticed it early...); so, the way to go is a "result_for_key" method that needs to be implemented by scopes which want to support canned queries requesting a preview.

Second off, I've some of that "new approach" implemented in the shell plugin, but we will need changes in plugin<->shell interface too, and for the unity8 shell side of things I need somebody from unity8 team. I hope this will happen at some point, but this enhancement is not a priority at the moment.