Work towards https://github.com/flutter/flutter/issues/143299.
Work towards https://github.com/flutter/flutter/issues/160043.
---
This PR implements, end-to-end, support for `matchesGoldenFile` when (a)
running with `package:integration_test` (b) on a device, such as an
Android emulator, Android device, iOS simulator, or iOS device, where
the _runner_ of a test file does not have process and local-file system
access.
There are multiple parts to this PR; I could make it smaller than 1K
lines, but the bulk of that is tests, and it would mean landing PRs that
are incomplete and unused, which does not seem useful - so instead here
is a quick overview of the PR's contents - questions/feedback welcome,
and I am willing to break code out or land incremental refactors if
requested.
1. Augmented `flutter_platform.dart` (used for iOS and Android), similar
to
[`flutter_web_platform.dart`](1398dc7eec/packages/flutter_tools/lib/src/test/flutter_web_platform.dart (L117-L128)),
now creates and uses
[`test_golden_comparator.dart`](https://github.com/flutter/flutter/blob/master/packages/flutter_tools/lib/src/test/test_golden_comparator.dart)
to proxy calls (coming from the VM service protocol) for golden-file
updates and comparisons to a `flutter_tester` process. A full
explanation of how (or why) it works this way is too hard to include
here, but see https://github.com/flutter/flutter/pull/160215 for more
details.
1. Added `VmServiceProxyGoldenFileComparator`, which is a currently
unused (outside of a single e2e test) comparator that forwards calls to
`compare` and `update` to the VM service protocol (of which, the other
side of this is implemented above, in `flutter_platform.dart`. The idea
is that this comparator would be used automatically when running in an
integration test on a device that requires it (similar to how web works
today), but that is **not** wired up yet and requires additional work in
`flutter_tools`.
1. Added two unit tests (of both the client and server), and a full
e2e-test using it to run `matchesGoldenFile`.
This auto-formats all *.dart files in the repository outside of the
`engine` subdirectory and enforces that these files stay formatted with
a presubmit check.
**Reviewers:** Please carefully review all the commits except for the
one titled "formatted". The "formatted" commit was auto-generated by
running `dev/tools/format.sh -a -f`. The other commits were hand-crafted
to prepare the repo for the formatting change. I recommend reviewing the
commits one-by-one via the "Commits" tab and avoiding Github's "Files
changed" tab as it will likely slow down your browser because of the
size of this PR.
---------
Co-authored-by: Kate Lovett <katelovett@google.com>
Co-authored-by: LongCatIsLooong <31859944+LongCatIsLooong@users.noreply.github.com>
Closes https://github.com/flutter/flutter/issues/66006.
From what I can tell in the multi-view effort a variation of
https://github.com/flutter/flutter/pull/88609 already landed, meaning
that the current device-pixel-ratio is being used (as the tests in
#88609 are now passing), and I believe that means we can remove the
override/hack.
Will rely on "Google Testing" to run a TGP internally, or do so myself
if necessary.
This change enables Flutter to generate multiple Scenes to be rendered into separate FlutterViews from a single widget tree. Each Scene is described by a separate render tree, which are all associated with the single widget tree.
This PR implements the framework-side mechanisms to describe the content to be rendered into multiple views. Separate engine-side changes are necessary to provide these views to the framework and to draw the framework-generated Scene into them.
## Summary of changes
The details of this change are described in [flutter.dev/go/multiple-views](https://flutter.dev/go/multiple-views). Below is a high-level summary organized by layers.
### Rendering layer changes
* The `RendererBinding` no longer owns a single `renderView`. In fact, it doesn't OWN any `RenderView`s at all anymore. Instead, it offers an API (`addRenderView`/`removeRenderView`) to add and remove `RenderView`s that then will be MANAGED by the binding. The `RenderView` itself is now owned by a higher-level abstraction (e.g. the `RawView` Element of the widgets layer, see below), who is also in charge of adding it to the binding. When added, the binding will interact with the `RenderView` to produce a frame (e.g. by calling `compositeFrame` on it) and to perform hit tests for incoming pointer events. Multiple `RenderView`s can be added to the binding (typically one per `FlutterView`) to produce multiple Scenes.
* Instead of owning a single `pipelineOwner`, the `RendererBinding` now owns the root of the `PipelineOwner` tree (exposed as `rootPipelineOwner` on the binding). Each `PipelineOwner` in that tree (except for the root) typically manages its own render tree typically rooted in one of the `RenderView`s mentioned in the previous bullet. During frame production, the binding will instruct each `PipelineOwner` of that tree to flush layout, paint, semantics etc. A higher-level abstraction (e.g. the widgets layer, see below) is in charge of adding `PipelineOwner`s to this tree.
* Backwards compatibility: The old `renderView` and `pipelineOwner` properties of the `RendererBinding` are retained, but marked as deprecated. Care has been taken to keep their original behavior for the deprecation period, i.e. if you just call `runApp`, the render tree bootstrapped by this call is rooted in the deprecated `RendererBinding.renderView` and managed by the deprecated `RendererBinding.pipelineOwner`.
### Widgets layer changes
* The `WidgetsBinding` no longer attaches the widget tree to an existing render tree. Instead, it bootstraps a stand-alone widget tree that is not backed by a render tree. For this, `RenderObjectToWidgetAdapter` has been replaced by `RootWidget`.
* Multiple render trees can be bootstrapped and attached to the widget tree with the help of the `View` widget, which internally is backed by a `RawView` widget. Configured with a `FlutterView` to render into, the `RawView` creates a new `PipelineOwner` and a new `RenderView` for the new render tree. It adds the new `RenderView` to the `RendererBinding` and its `PipelineOwner` to the pipeline owner tree.
* The `View` widget can only appear in certain well-defined locations in the widget tree since it bootstraps a new render tree and does not insert a `RenderObject` into an ancestor. However, almost all Elements expect that their children insert `RenderObject`s, otherwise they will not function properly. To produce a good error message when the `View` widget is used in an illegal location, the `debugMustInsertRenderObjectIntoSlot` method has been added to Element, where a child can ask whether a given slot must insert a RenderObject into its ancestor or not. In practice, the `View` widget can be used as a child of the `RootWidget`, inside the `view` slot of the `ViewAnchor` (see below) and inside a `ViewCollection` (see below). In those locations, the `View` widget may be wrapped in other non-RenderObjectWidgets (e.g. InheritedWidgets).
* The new `ViewAnchor` can be used to create a side-view inside a parent `View`. The `child` of the `ViewAnchor` widget renders into the parent `View` as usual, but the `view` slot can take on another `View` widget, which has access to all inherited widgets above the `ViewAnchor`. Metaphorically speaking, the view is anchored to the location of the `ViewAnchor` in the widget tree.
* The new `ViewCollection` widget allows for multiple sibling views as it takes a list of `View`s as children. It can be used in all the places that accept a `View` widget.
## Google3
As of July 5, 2023 this change passed a TAP global presubmit (TGP) in google3: tap/OCL:544707016:BASE:545809771:1688597935864:e43dd651
## Note to reviewers
This change is big (sorry). I suggest focusing the initial review on the changes inside of `packages/flutter` first. The majority of the changes describe above are implemented in (listed in suggested review order):
* `rendering/binding.dart`
* `widgets/binding.dart`
* `widgets/view.dart`
* `widgets/framework.dart`
All other changes included in the PR are basically the fallout of what's implemented in those files. Also note that a lot of the lines added in this PR are documentation and tests.
I am also very happy to walk reviewers through the code in person or via video call, if that is helpful.
I appreciate any feedback.
## Feedback to address before submitting ("TODO")
* Revert "Remove references to BindingBase.window (#122119)"
This reverts commit c7681f00cf.
* Revert "Remove another reference to BindingBase.window (#122341)"
This reverts commit 6ec4445063.
* Revert "Reland (2): Removes single window assumptions from `flutter_test` (#122233)"
This reverts commit eb3d317ea0.
* Revert "Remove single view assumption from TestViewConfiguration (#122352)"
This reverts commit 927289fb4e.
* Revert "Updates `flutter/test/cupertino` to no longer use `TestWindow` (#122325)"
This reverts commit 67e17e45f0.
* Revert "Updates `flutter/test/gestures` to no longer reference `TestWindow` (#122327)"
This reverts commit c2a5111cc0.
* Revert "Updates `flutter/test/rendering` to no longer use `TestWindow` (#122347)"
This reverts commit 28b65e089b.
* Revert "Updates `flutter_localizations/test` to stop using `TestWindow` (#122321)"
This reverts commit 01367d52d7.
* Fix screenshot testing for flutter web integration_test
* update packages
* fix method signature and todo
* Run tests on CI
* fix type
* remove silences
* Add docs
* fix comment
* fix whitespace
* review comments
* Use `curly_braces_in_flow_control_structures` for `packages/flutter_driver`
* Use `curly_braces_in_flow_control_structures` for `packages/flutter_goldens`
* Use `curly_braces_in_flow_control_structures` for `packages/flutter_goldens_client`
* Use `curly_braces_in_flow_control_structures` for `packages/flutter_localizations`
* Use `curly_braces_in_flow_control_structures` for `packages/flutter_test`
* Use `curly_braces_in_flow_control_structures` for `packages/flutter_web_plugins`
* fix comments
* Use `curly_braces_in_flow_control_structures` for `packages/integration_test`
* fix indentation
