Some render box subclasses have a specific layout contract that is tightly coupled with other render box subclasses (e.g. two private classes in a local project file). In these cases, it is also possible that they use a constraints object that is a subclass of `BoxConstraints`. To allow for this, this change makes the `constraints` argument to `RenderBox.computeDryLayout()` a covariant argument.
For completeness' sake, this updates the other render objects in the rendering package to also use the covariant keyword for this argument.
Fixes https://github.com/flutter/flutter/issues/59413
This relocates `mock_canvas.dart` and `recording_canvas.dart` from `flutter/test/rendering` to `flutter_test`.
The testing functionality afforded by mock_canvas should be available to everyone, not just the framework. :)
mock_canvas.dart needed a bit of cleanup - things like formatting and super parameters.
* Add test for RenderProxyBoxMixin; clarify doc, resolve TODO
The TODO comment suggested this mixin would no longer be needed once
a Dart issue on inherited constructors was fixed:
https://github.com/dart-lang/sdk/issues/31543
That issue is now long since fixed, so I went to go carry out the TODO.
But in doing so, I realized that the mixin's documentation was more
right than the TODO comment: even with that issue fixed, there is a
legitimate use case for this mixin, namely to reuse the implementation
of RenderProxyBox in a class that also inherits from some other base
class. Moreover, searching GitHub I found an example of a library
that makes real use of that capability.
So I think the right resolution is to accept that this separation
is useful and delete the TODO.
Then, add a test with an extremely simplified sketch of that
real-world example. In case someone in the future attempts to
simplify this mixin away, the test will point us at the use case
that would be broken by such a change.
Also remove the only in-tree use of the mixin, which was redundant;
and expand the mixin's documentation to advise about that case.
* Tweak formatting
Co-authored-by: Michael Goderbauer <goderbauer@google.com>
* Cut comments
---------
Co-authored-by: Michael Goderbauer <goderbauer@google.com>
* Redesigns the interface between MouseTracker and RendererBinding&RenderView.
* Simplifies the structure of RenderMouseRegion.
* Extracts the common utility code between mouse_tracker_test and mouse_tracker_cursor_test.
* Add clipBehavior to RenderFlex
* Add clipBehavior to FittedBox
* Add clipBehavior to Flex and FittedBox
* Add clipBehavior to UnconstrainedBox
* Add clipBehavior to Stack and Wrap
* Add clipBehavior to TextEditable
* Add clipBehavior to ListWheelScrollView
* Add clipBehavior to SingleChildScrollView
* Add clipBehavior to RenderViewportBase's widgets
Those widgets are NestedScrollView and ShrinkWrappingViewport.
* Fix tests
* Remove enum Overflow and fix typo
* Remove clipToSize
* Analyze fix
* Remove Mixin and other small fixes
* Fix tests and respect Stack's default clipBehavior
* Add Overflow back to make it non-breaking
* Restore clipBehavior to make it non-breaking
* Small fixes
* Fix rebase
