This makes the about page show the licenses of all the Dart packages that a Flutter app uses.
Issues that this does not yet resolve:
- I'm still working on getting the full list of licenses for the sky_engine package.
- Some of the licenses don't print very readably.
- There's no scrollbar on the license page.
I'll provide fixes for the first two in the coming days, but this should unblock anyone who is wanting to see something here, even if it's not quite complete. :-)
----
The patch makes the following changes:
- The license registry is now asynchronous, since the data comes from disk.
- I moved the default license collector from the foundation package to the services package since it uses the default asset bundle now.
- The FLX builder now includes the LICENSE files of each Dart package mentioned in the `.packages` file.
This introduces the key parts of a paginated data table, not including
the built-in pagination features.
* Provide more data for the data table demo, so there's data to page.
* Introduce a ChangeNotifier class which abstracts out
addListener/removeListener/notifyListeners. We might be able to use
this to simplify existing classes as well, though this patch doesn't
do that.
* Introduce DataTableSource, a delegate for getting data for data
tables. This will also be used by ScrollingDataTable in due course.
* Introduce PaginatedDataTable, a widget that wraps DataTable and only
shows N rows at a time, fed by a DataTableSource.
This makes it possible to substitute 'flutter run' for 'flutter test'
and actually watch a test run on a device.
For any test that depends on flutter_test:
1. Remove any import of 'package:test/test.dart'.
2. Replace `testWidgets('...', (WidgetTester tester) {`
with `testWidgets('...', (WidgetTester tester) async {`
3. Add an "await" in front of calls to any of the following:
* tap()
* tapAt()
* fling()
* flingFrom()
* scroll()
* scrollAt()
* pump()
* pumpWidget()
4. Replace any calls to `tester.flushMicrotasks()` with calls to
`await tester.idle()`.
There's a guarding API that you can use, if you have particularly
complicated tests, to get better error messages. Search for
TestAsyncUtils.
* Refactor widget test framework
Instead of:
```dart
test("Card Collection smoke test", () {
testWidgets((WidgetTester tester) {
```
...you now say:
```dart
testWidgets("Card Collection smoke test", (WidgetTester tester) {
```
Instead of:
```dart
expect(tester, hasWidget(find.text('hello')));
```
...you now say:
```dart
expect(find.text('hello'), findsOneWidget);
```
Instead of the previous API (exists, widgets, widget, stateOf,
elementOf, etc), you now have the following comprehensive API. All these
are functions that take a Finder, except the all* properties.
* `any()` - true if anything matches, c.f. `Iterable.any`
* `allWidgets` - all the widgets in the tree
* `widget()` - the one and only widget that matches the finder
* `firstWidget()` - the first widget that matches the finder
* `allElements` - all the elements in the tree
* `element()` - the one and only element that matches the finder
* `firstElement()` - the first element that matches the finder
* `allStates` - all the `State`s in the tree
* `state()` - the one and only state that matches the finder
* `firstState()` - the first state that matches the finder
* `allRenderObjects` - all the render objects in the tree
* `renderObject()` - the one and only render object that matches the finder
* `firstRenderObject()` - the first render object that matches the finder
There's also `layers' which returns the list of current layers.
`tap`, `fling`, getCenter, getSize, etc, take Finders, like the APIs
above, and expect there to only be one matching widget.
The finders are:
* `find.text(String text)`
* `find.widgetWithText(Type widgetType, String text)`
* `find.byKey(Key key)`
* `find.byType(Type type)`
* `find.byElementType(Type type)`
* `find.byConfig(Widget config)`
* `find.byWidgetPredicate(WidgetPredicate predicate)`
* `find.byElementPredicate(ElementPredicate predicate)`
The matchers (for `expect`) are:
* `findsNothing`
* `findsWidgets`
* `findsOneWidget`
* `findsNWidgets(n)`
* `isOnStage`
* `isOffStage`
* `isInCard`
* `isNotInCard`
Benchmarks now use benchmarkWidgets instead of testWidgets.
Also, for those of you using mockers, `serviceMocker` now automatically
handles the binding initialization.
This patch also:
* changes how tests are run so that we can more easily swap the logic
out for a "real" mode instead of FakeAsync.
* introduces CachingIterable.
* changes how flutter_driver interacts with the widget tree to use the
aforementioned new API rather than ElementTreeTester, which is gone.
* removes ElementTreeTester.
* changes the semantics of a test for scrollables because we couldn't
convince ourselves that the old semantics made sense; it only worked
before because flushing the microtasks after every event was broken.
* fixes the flushing of microtasks after every event.
* Reindent the tests
* Fix review comments
