* 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
Turns out a common use for Baseline is making sure that the child's
baseline is higher than it otherwise would be, e.g. with the Material
font or other symbols.
Note that the /// part of the doc was published, only the // line was
omitted. This means that we can safely put // comments between /// docs
and the member they are documenting.
Instead of using properties, TextPainter now receives min and max width as
parameters to layout. Also, this patch integrates the intrinsic sizing logic
into the main layout function, which satisfies all the existing uses cases.
Apps that didn't use [WidgetsApp] were not sending the `'Widgets
completed first useful frame'` notification. This fixes that by making
the code cleaner.
Some inherited widgets want to call this function direction, for example to
notify children when a mutable model object changes. Exposing this function to
subclasses of InheritedWidget is clear then forcing them to compute
updateShouldNotify for mutable model objects.
* add import guidance to library-level docs
* add import docs to other packages
* fix review comment
* clarify which libraries aren't meant to be directly imported
This patch adds an option to Scaffold to disable resizing the body to avoid the
window padding. This lets developers create layouts that are stable when the
keyboard overlays the app.
Fixes#3565
Wait until the end of the microtask to tell gesture recognizers that
they've won in the gesture arena. This lets recognizers dispose reject
themselves at arbitrary times without triggering gestures in awkward
call stacks.
Fixes#3183
Previously we were locking down the state even when calling layout in
LazyBlock. Now we lock only when building children. Making this work well
involved moving the catch out of lockState and into the few callers who
actually wanted it.
Fixes#3534
A flow layout is optimized for reposition children with transformation
matrices. A flow layout can animate the position of its children very
efficiently.
Prior to this patch, we were pushing two frames each time the cursor blinked.
In turning the cursor on or off, the markNeedsPaint call was triggering another
frame to be scheduled because we cleared a bit in the scheduler at the
beginning of the frame instead of at the end of the frame.
To implement scheduling correctly, we actually need two bits: one for
ensureVisualUpdate, which just promises to get to the end of the pipeline soon,
and scheduleFrame, which promises to get to the beginning of the pipeline soon.
(Reland)
This adds in particular the ability to track the time at which the
framework boots up, and the time at which we are confident we have
completed the first useful frame.
This reorders some classes so that this file makes more sense, and adds
a bunch of docs. It also makes the following changes:
* Move allElements from Instrumentation to TestWidgets. (Instrumentation
is going away.)
* Remove findElements.
* Rename byElement to byElementPredicate
* Rename byPredicate to byWidgetPredicate
* Implement _WidgetPredicateFinder so that byWidgetPredicate has good
messages
* Fix one use of byElementPredicate to use byWidgetPredicate.
Previously the widgets layer only provided a concrete binding, which
makes it awkward to extend it compared to other bindings. This moves
widgets to the same style as the other layers.
In a subsequent patch I'll use this to make the tests layer saner.
