Issue by Hixie
Monday Oct 05, 2015 at 21:18 GMT
Originally opened as https://github.com/flutter/engine/issues/1494

Right now Focus.at() defaults to returning true if there's no scope, which is intentional to make it easier to write trivial apps with a single focusable widget. But it means that when you add a second one, things break in unobvious ways. We should catch that case and assert with a useful message.