specifically re tests:

• check that the darkTheme is used when a mock window or the platform sends Brightness.dark
• check that the theme and darkTheme toggles automatically via a descendent Material widget when the platform toggles
• check that the theme is indeed used when darkTheme is undefined.

In general, I think it's a good idea to run flutter test --coverage and making sure all the new lines are covered until we have an infra to display it in GitHub. You can see the lcov with a vscode extension or something (or you can just read the output file).

@HansMuller @goderbauer @xster - I just pushed a number of updates based on comments. Can you all do another pass?

Looks like cirrus is not too happy, though.

@matthew-carroll How can I change the platformBrightness value and also affect the MaterialApp theme? I implemented adding a MediaQuery with my custom value for platformBrightness similar to how it was done here. I even tried setting state of the widget containing the MaterialApp via WidgetBindingsObserver's didChangePlatformBrightness. The MediaQuery has the correct value down the tree, but the theme does not change accordingly. However, when I toggle the device to dark mode it works fine. What part am I missing?

The MaterialApp has both theme and darkTheme populated.

@creativecreatorormaybenot can you please file this question as an issue instead of a PR comment? Also, can you please include as much of your actual code as possible? I need to see exactly what you're doing to be able to comment.